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Sample records for air brake tests

  1. 49 CFR 232.305 - Single car air brake tests.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... with 5 U.S.C. 552(a) and 1 CFR part 51. You may obtain a copy of the incorporated document from the... 49 Transportation 4 2014-10-01 2014-10-01 false Single car air brake tests. 232.305 Section 232... car air brake tests. (a) Single car air brake tests shall be performed by a qualified person...

  2. 49 CFR 232.305 - Single car air brake tests.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... with 5 U.S.C. 552(a) and 1 CFR part 51. You may obtain a copy of the incorporated document from the... 49 Transportation 4 2012-10-01 2012-10-01 false Single car air brake tests. 232.305 Section 232... car air brake tests. (a) Single car air brake tests shall be performed by a qualified person...

  3. 49 CFR 232.305 - Single car air brake tests.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... with 5 U.S.C. 552(a) and 1 CFR part 51. You may obtain a copy of the incorporated document from the... 49 Transportation 4 2013-10-01 2013-10-01 false Single car air brake tests. 232.305 Section 232... car air brake tests. (a) Single car air brake tests shall be performed by a qualified person...

  4. 49 CFR 232.305 - Single car air brake tests.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... with 5 U.S.C. 552(a) and 1 CFR part 51. You may obtain a copy of the incorporated document from the... 49 Transportation 4 2011-10-01 2011-10-01 false Single car air brake tests. 232.305 Section 232... car air brake tests. (a) Single car air brake tests shall be performed by a qualified person...

  5. 49 CFR 232.305 - Single car air brake tests.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... with 5 U.S.C. 552(a) and 1 CFR part 51. You may obtain a copy of the incorporated document from the... 49 Transportation 4 2010-10-01 2010-10-01 false Single car air brake tests. 232.305 Section 232... car air brake tests. (a) Single car air brake tests shall be performed by a qualified person...

  6. 49 CFR 232.217 - Train brake tests conducted using yard air.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Train brake tests conducted using yard air. 232... Train brake tests conducted using yard air. (a) When a train air brake system is tested from a yard air... reduction of brake pipe air pressure at the same, or slower, rate as an engineer's brake valve. (b) The...

  7. 49 CFR 232.217 - Train brake tests conducted using yard air.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Train brake tests conducted using yard air. 232... Train brake tests conducted using yard air. (a) When a train air brake system is tested from a yard air... reduction of brake pipe air pressure at the same, or slower, rate as an engineer's brake valve. (b) The...

  8. 49 CFR 232.217 - Train brake tests conducted using yard air.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Train brake tests conducted using yard air. 232... Train brake tests conducted using yard air. (a) When a train air brake system is tested from a yard air... reduction of brake pipe air pressure at the same, or slower, rate as an engineer's brake valve. (b) The...

  9. 49 CFR 232.217 - Train brake tests conducted using yard air.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Train brake tests conducted using yard air. 232... Train brake tests conducted using yard air. (a) When a train air brake system is tested from a yard air... reduction of brake pipe air pressure at the same, or slower, rate as an engineer's brake valve. (b) The...

  10. 49 CFR 232.217 - Train brake tests conducted using yard air.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Train brake tests conducted using yard air. 232... Train brake tests conducted using yard air. (a) When a train air brake system is tested from a yard air... reduction of brake pipe air pressure at the same, or slower, rate as an engineer's brake valve. (b) The...

  11. 49 CFR 229.29 - Air brake system calibration, maintenance, and testing.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Air brake system calibration, maintenance, and... Inspections and Tests § 229.29 Air brake system calibration, maintenance, and testing. (a) A locomotive's air brake system shall receive the calibration, maintenance, and testing as prescribed in this section....

  12. 49 CFR 229.29 - Air brake system calibration, maintenance, and testing.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Air brake system calibration, maintenance, and... Inspections and Tests § 229.29 Air brake system calibration, maintenance, and testing. (a) A locomotive's air brake system shall receive the calibration, maintenance, and testing as prescribed in this section....

  13. 49 CFR 229.29 - Air brake system calibration, maintenance, and testing.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Air brake system calibration, maintenance, and... Inspections and Tests § 229.29 Air brake system calibration, maintenance, and testing. (a) A locomotive's air brake system shall receive the calibration, maintenance, and testing as prescribed in this section....

  14. 49 CFR 232.307 - Modification of the single car air brake test procedures.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Modification of the single car air brake test... Requirements § 232.307 Modification of the single car air brake test procedures. (a) Request. The AAR or other authorized representative of the railroad industry may seek modification of the single car air brake...

  15. 49 CFR 232.307 - Modification of the single car air brake test procedures.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Modification of the single car air brake test... Requirements § 232.307 Modification of the single car air brake test procedures. (a) Request. The AAR or other authorized representative of the railroad industry may seek modification of the single car air brake...

  16. 78 FR 44189 - Petition for Modification of Single Car Air Brake Test Procedures

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-23

    ..., 2000 (65 FR 19477). Robert C. Lauby, Deputy Associate Administrator for Regulatory and Legislative... Federal Railroad Administration Petition for Modification of Single Car Air Brake Test Procedures In... the Federal Railroad Administration (FRA) per 49 CFR 232.307 to modify the single car air brake...

  17. 49 CFR 232.307 - Modification of the single car air brake test procedures.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Modification of the single car air brake test procedures. 232.307 Section 232.307 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRAKE SYSTEM SAFETY STANDARDS FOR FREIGHT AND OTHER NON-PASSENGER TRAINS...

  18. 76 FR 34801 - Petition for Modification of Single Car Air Brake Test Procedures

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-14

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF TRANSPORTATION Federal Railroad Administration Petition for Modification of Single Car Air Brake Test Procedures In accordance with Part 232 of Title 49 of the Code of Federal Regulations (CFR), this document provides the public notice that by a document...

  19. Deployable Engine Air Brake

    NASA Technical Reports Server (NTRS)

    2014-01-01

    On approach, next-generation aircraft are likely to have airframe noise levels that are comparable to or in excess of engine noise. ATA Engineering, Inc. (ATA) is developing a novel quiet engine air brake (EAB), a device that generates "equivalent drag" within the engine through stream thrust reduction by creating a swirling outflow in the turbofan exhaust nozzle. Two Phase II projects were conducted to mature this technology: (1) a concept development program (CDP) and (2) a system development program (SDP).

  20. Vehicle brake testing system

    DOEpatents

    Stevens, Samuel S [Harriman, TN; Hodgson, Jeffrey W [Lenoir City, TN

    2002-11-19

    This invention relates to a force measuring system capable of measuring forces associated with vehicle braking and of evaluating braking performance. The disclosure concerns an invention which comprises a first row of linearly aligned plates, a force bearing surface extending beneath and beside the plates, vertically oriented links and horizontally oriented links connecting each plate to a force bearing surface, a force measuring device in each link, a transducer coupled to each force measuring device, and a computing device coupled to receive an output signal from the transducer indicative of measured force in each force measuring device. The present invention may be used for testing vehicle brake systems.

  1. 49 CFR 570.57 - Air brake system and air-over-hydraulic brake subsystem.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 6 2010-10-01 2010-10-01 false Air brake system and air-over-hydraulic brake... STANDARDS Vehicles With GVWR of More Than 10,000 Pounds § 570.57 Air brake system and air-over-hydraulic brake subsystem. The following requirements apply to vehicles with air brake and...

  2. Air brake-dynamometer accurately measures torque

    NASA Technical Reports Server (NTRS)

    1965-01-01

    Air brake-dynamometer assembly combines the principles of the air turbine and the air pump to apply braking torque. The assembly absorbs and measures power outputs of rotating machinery over a wide range of shaft speeds. It can also be used as an air turbine.

  3. 49 CFR 238.317 - Class II brake test.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Class II brake test. 238.317 Section 238.317... Requirements for Tier I Passenger Equipment § 238.317 Class II brake test. (a) A Class II brake test shall be.... In these circumstances, a Class II brake test shall be performed prior to the train's departure...

  4. 49 CFR 238.317 - Class II brake test.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Class II brake test. 238.317 Section 238.317... Requirements for Tier I Passenger Equipment § 238.317 Class II brake test. (a) A Class II brake test shall be.... In these circumstances, a Class II brake test shall be performed prior to the train's departure...

  5. 49 CFR 238.317 - Class II brake test.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Class II brake test. 238.317 Section 238.317... Requirements for Tier I Passenger Equipment § 238.317 Class II brake test. (a) A Class II brake test shall be.... In these circumstances, a Class II brake test shall be performed prior to the train's departure...

  6. 49 CFR 238.317 - Class II brake test.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Class II brake test. 238.317 Section 238.317... Requirements for Tier I Passenger Equipment § 238.317 Class II brake test. (a) A Class II brake test shall be.... In these circumstances, a Class II brake test shall be performed prior to the train's departure...

  7. 49 CFR 232.215 - Transfer train brake tests.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Transfer train brake tests. 232.215 Section 232... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRAKE SYSTEM SAFETY STANDARDS FOR FREIGHT AND OTHER NON-PASSENGER... brake tests. (a) A transfer train, as defined in § 232.5, shall receive a brake test performed by...

  8. 49 CFR 232.215 - Transfer train brake tests.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Transfer train brake tests. 232.215 Section 232... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRAKE SYSTEM SAFETY STANDARDS FOR FREIGHT AND OTHER NON-PASSENGER... brake tests. (a) A transfer train, as defined in § 232.5, shall receive a brake test performed by...

  9. 49 CFR 232.215 - Transfer train brake tests.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Transfer train brake tests. 232.215 Section 232... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRAKE SYSTEM SAFETY STANDARDS FOR FREIGHT AND OTHER NON-PASSENGER... brake tests. (a) A transfer train, as defined in § 232.5, shall receive a brake test performed by...

  10. 49 CFR 232.215 - Transfer train brake tests.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Transfer train brake tests. 232.215 Section 232... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRAKE SYSTEM SAFETY STANDARDS FOR FREIGHT AND OTHER NON-PASSENGER... brake tests. (a) A transfer train, as defined in § 232.5, shall receive a brake test performed by...

  11. 49 CFR 238.313 - Class I brake test.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... shall be performed at the air pressure at which the train's air brakes will be operated, but not less... the case of tread or disc brakes by determining that the brake shoe or pad provides pressure to the... pressure changes at the rear of the train is verified, which may be accomplished by observation of...

  12. 27. UPPER STATION, LOWER FLOOR, BULL WHEEL, BRAKE AIR CYLINDER. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    27. UPPER STATION, LOWER FLOOR, BULL WHEEL, BRAKE AIR CYLINDER. - Monongahela Incline Plane, Connecting North side of Grandview Avenue at Wyoming Street with West Carson Street near Smithfield Street, Pittsburgh, Allegheny County, PA

  13. 22. General view inside air brake shop section of roundhouse. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    22. General view inside air brake shop section of roundhouse. View to west. - Duluth & Iron Range Rail Road Company Shops, Roundhouse, Southwest of downtown Two Harbors, northwest of Agate Bay, Two Harbors, Lake County, MN

  14. 6. North wall and east end of air brake shop ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. North wall and east end of air brake shop section of roundhouse at center. East end of boiler shop section of roundhouse to the right of air brake shop. East end of blacksmith shop section of roundhouse at far right. View to southeast. - Duluth & Iron Range Rail Road Company Shops, Roundhouse, Southwest of downtown Two Harbors, northwest of Agate Bay, Two Harbors, Lake County, MN

  15. 49 CFR 238.319 - Running brake test.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Running brake test. 238.319 Section 238.319... Requirements for Tier I Passenger Equipment § 238.319 Running brake test. (a) As soon as conditions safely permit, a running brake test shall be performed on each passenger train after the train has received,...

  16. 49 CFR 238.319 - Running brake test.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Running brake test. 238.319 Section 238.319... Requirements for Tier I Passenger Equipment § 238.319 Running brake test. (a) As soon as conditions safely permit, a running brake test shall be performed on each passenger train after the train has received,...

  17. 49 CFR 238.319 - Running brake test.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Running brake test. 238.319 Section 238.319... Requirements for Tier I Passenger Equipment § 238.319 Running brake test. (a) As soon as conditions safely permit, a running brake test shall be performed on each passenger train after the train has received,...

  18. 49 CFR 238.319 - Running brake test.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Running brake test. 238.319 Section 238.319... Requirements for Tier I Passenger Equipment § 238.319 Running brake test. (a) As soon as conditions safely permit, a running brake test shall be performed on each passenger train after the train has received,...

  19. 49 CFR 238.319 - Running brake test.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Running brake test. 238.319 Section 238.319... Requirements for Tier I Passenger Equipment § 238.319 Running brake test. (a) As soon as conditions safely permit, a running brake test shall be performed on each passenger train after the train has received,...

  20. 49 CFR 238.313 - Class I brake test.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Class I brake test. 238.313 Section 238.313... Requirements for Tier I Passenger Equipment § 238.313 Class I brake test. (a) Each commuter and short-distance intercity passenger train shall receive a Class I brake test once each calendar day that the train is...

  1. 49 CFR 238.315 - Class IA brake test.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Class IA brake test. 238.315 Section 238.315... Requirements for Tier I Passenger Equipment § 238.315 Class IA brake test. (a) Except as provided in paragraph (b) of this section, either a Class I or a Class IA brake test shall be performed: (1) Prior to...

  2. 49 CFR 238.315 - Class IA brake test.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Class IA brake test. 238.315 Section 238.315... Requirements for Tier I Passenger Equipment § 238.315 Class IA brake test. (a) Except as provided in paragraph (b) of this section, either a Class I or a Class IA brake test shall be performed: (1) Prior to...

  3. 49 CFR 238.315 - Class IA brake test.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Class IA brake test. 238.315 Section 238.315... Requirements for Tier I Passenger Equipment § 238.315 Class IA brake test. (a) Except as provided in paragraph (b) of this section, either a Class I or a Class IA brake test shall be performed: (1) Prior to...

  4. 49 CFR 238.313 - Class I brake test.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Class I brake test. 238.313 Section 238.313... Requirements for Tier I Passenger Equipment § 238.313 Class I brake test. (a) Each commuter and short-distance intercity passenger train shall receive a Class I brake test once each calendar day that the train is...

  5. 49 CFR 238.315 - Class IA brake test.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Class IA brake test. 238.315 Section 238.315... Requirements for Tier I Passenger Equipment § 238.315 Class IA brake test. (a) Except as provided in paragraph (b) of this section, either a Class I or a Class IA brake test shall be performed: (1) Prior to...

  6. 49 CFR 238.315 - Class IA brake test.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Class IA brake test. 238.315 Section 238.315... Requirements for Tier I Passenger Equipment § 238.315 Class IA brake test. (a) Except as provided in paragraph (b) of this section, either a Class I or a Class IA brake test shall be performed: (1) Prior to...

  7. 49 CFR 238.313 - Class I brake test.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Class I brake test. 238.313 Section 238.313... Requirements for Tier I Passenger Equipment § 238.313 Class I brake test. (a) Each commuter and short-distance intercity passenger train shall receive a Class I brake test once each calendar day that the train is...

  8. 49 CFR 238.313 - Class I brake test.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Class I brake test. 238.313 Section 238.313... Requirements for Tier I Passenger Equipment § 238.313 Class I brake test. (a) Each commuter and short-distance intercity passenger train shall receive a Class I brake test once each calendar day that the train is...

  9. 5. Machine shop and air brake shop sections of roundhouse ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. Machine shop and air brake shop sections of roundhouse in background. Foundry (MN-99-B) in foreground. View to south. - Duluth & Iron Range Rail Road Company Shops, Roundhouse, Southwest of downtown Two Harbors, northwest of Agate Bay, Two Harbors, Lake County, MN

  10. 49 CFR 232.215 - Transfer train brake tests.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Transfer train brake tests. 232.215 Section 232... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRAKE SYSTEM SAFETY STANDARDS FOR FREIGHT AND OTHER NON-PASSENGER TRAINS AND EQUIPMENT; END-OF-TRAIN DEVICES Inspection and Testing Requirements § 232.215 Transfer...

  11. A Comparative Study on Automotive Brake Testing Standards

    NASA Astrophysics Data System (ADS)

    Kumbhar, Bhau Kashinath; Patil, Satyajit Ramchandra; Sawant, Suresh Maruti

    2016-06-01

    Performance testing of automotive brakes involves determination of stopping time, distance and deceleration level. Braking performance of an automobile is required to be ensured for various surfaces like dry, wet, concrete, bitumen etc. as well as for prolonged applications. Various brake testing standards are used worldwide to assure vehicle and pedestrian safety. This article presents methodologies used for automotive service brake testing for two wheelers. The main contribution of this work lies in comparative study of three main brake testing standards; viz. Indian Standards, Federal Motor Vehicle Safety Standards and European Economic Commission Standards. This study shall help the policy makers to choose the best criteria out of these three while formulating newer edition of testing standards.

  12. Application of Anti-slip/skid Re-adhesion Control System Based on Disturbance Observer to a Skid Control Considering Cooperation Control of Air Bake and Electric Brake

    NASA Astrophysics Data System (ADS)

    Kadowaki, Satoshi; Ohishi, Kiyoshi; Sano, Takashi; Yasukawa, Shinobu

    We have already proposed the anti-slip re-adhesion control based on disturbance observer and sensor-less vector control at acceleration mode. This paper proposes a new anti-skid re-adhesion control based on disturbance observer at braking mode. The numerical simulation and experimental results point out that the proposed anti-skid re-adhesion control system has the desired driving wheel torque response for the tested bogie system of electric train. An actual train uses both electric brake and air brake in the high-speed range. Hence, this paper proposes a new anti-skid re-adhesion control considering the air brake, which carries out the cooperation control of electric brake and air brake in order to realize a fine re-adhesion control. The numerical simulation results point out that the proposed system has the desired driving wheel torque response and a fine anti-skid re-adhesion control.

  13. 49 CFR 570.57 - Air brake system and air-over-hydraulic brake subsystem.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...-tension shall be sufficient to prevent slippage. Inspection procedure. With the air system charged, open... sufficient to prevent slippage. Inspection procedure. With the air system charged, open the drain cocks...

  14. 49 CFR 570.57 - Air brake system and air-over-hydraulic brake subsystem.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...-tension shall be sufficient to prevent slippage. Inspection procedure. With the air system charged, open... sufficient to prevent slippage. Inspection procedure. With the air system charged, open the drain cocks...

  15. 49 CFR 570.57 - Air brake system and air-over-hydraulic brake subsystem.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...-tension shall be sufficient to prevent slippage. Inspection procedure. With the air system charged, open... sufficient to prevent slippage. Inspection procedure. With the air system charged, open the drain cocks...

  16. 49 CFR 570.57 - Air brake system and air-over-hydraulic brake subsystem.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...-tension shall be sufficient to prevent slippage. Inspection procedure. With the air system charged, open... sufficient to prevent slippage. Inspection procedure. With the air system charged, open the drain cocks...

  17. 49 CFR 238.317 - Class II brake test.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Class II brake test. 238.317 Section 238.317 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION PASSENGER EQUIPMENT SAFETY STANDARDS Inspection, Testing, and Maintenance Requirements for Tier I Passenger Equipment...

  18. 49 CFR 232.205 - Class I brake test-initial terminal inspection.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... as follows: (A) Charge the air brake system to the pressure at which the train will be operated, and the pressure at the rear of the train shall be within 15 psi of the pressure at which the train will... for maintaining brake pipe pressure at a constant level during a 20-psi brake pipe service...

  19. 49 CFR 232.205 - Class I brake test-initial terminal inspection.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... as follows: (A) Charge the air brake system to the pressure at which the train will be operated, and the pressure at the rear of the train shall be within 15 psi of the pressure at which the train will... for maintaining brake pipe pressure at a constant level during a 20-psi brake pipe service...

  20. 49 CFR 232.205 - Class I brake test-initial terminal inspection.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... as follows: (A) Charge the air brake system to the pressure at which the train will be operated, and the pressure at the rear of the train shall be within 15 psi of the pressure at which the train will... for maintaining brake pipe pressure at a constant level during a 20-psi brake pipe service...

  1. Development of aircraft brake materials. [evaluation of metal and ceramic materials in sliding tests simulation of aircraft braking

    NASA Technical Reports Server (NTRS)

    Ho, T. L.; Peterson, M. B.

    1974-01-01

    The requirements of brake materials were outlined and a survey made to select materials to meet the needs of high temperature brakes. A number of metals and ceramic materials were selected and evaluated in sliding tests which simulated aircraft braking. Nickel, molybdenum tungsten, Zr02, high temperature cements and carbons were tested. Additives were then incorporated into these materials to optimize their wear or strength behavior with particular emphasis on nickel and molybdenum base materials and a high temperature potassium silicate cement. Optimum materials were developed which improved wear behavior over conventional brake materials in the simulated test. The best materials are a nickel, aluminum oxide, lead tungstate composition containing graphite or molybdenum disulphite; a molybdenum base material containing LPA100 (an intermetallic compound of cobalt, molybdenum, and silicon); and a carbon material (P5).

  2. 49 CFR 232.207 - Class IA brake tests-1,000-mile inspection.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Class IA brake tests-1,000-mile inspection. 232... Class IA brake tests—1,000-mile inspection. (a) Except as provided in § 232.213, each train shall receive a Class IA brake test performed by a qualified person, as defined in § 232.5, at a location...

  3. 49 CFR 232.207 - Class IA brake tests-1,000-mile inspection.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Class IA brake tests-1,000-mile inspection. 232... Class IA brake tests—1,000-mile inspection. (a) Except as provided in § 232.213, each train shall receive a Class IA brake test performed by a qualified person, as defined in § 232.5, at a location...

  4. 49 CFR 232.205 - Class I brake test-initial terminal inspection.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Class I brake test-initial terminal inspection...) FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRAKE SYSTEM SAFETY STANDARDS FOR FREIGHT... § 232.205 Class I brake test-initial terminal inspection. (a) Each train and each car in the train...

  5. Heavy and Overweight Vehicle Brake Testing: Five-Axle Combination Tractor-Flatbed Final Report

    SciTech Connect

    Lascurain, Mary Beth; Capps, Gary J; Franzese, Oscar

    2013-10-01

    The Federal Motor Carrier Safety Administration, in coordination with the Federal Highway Administration, sponsored the Heavy and Overweight Vehicle Brake Testing (HOVBT) program in order to provide information about the effect of gross vehicle weight (GVW) on braking performance. Because the Federal Motor Carrier Safety Regulations limit the number of braking system defects that may exist for a vehicle to be allowed to operate on the roadways, the examination of the effect of brake defects on brake performance for increased loads is also relevant. The HOVBT program seeks to provide relevant information to policy makers responsible for establishing load limits, beginning with providing test data for a combination tractor/trailer. This testing was conducted on a five-axle combination vehicle with tractor brakes meeting the Reduced Stopping Distance requirement rulemaking. This report provides a summary of the testing activities, the results of various analyses of the data, and recommendations for future research. Following a complete brake rebuild, instrumentation, and brake burnish, stopping tests were performed from 20 and 40 mph with various brake application pressures (15 psi, 25 psi, 35 psi, 45 psi, 55 psi, and full system pressure). These tests were conducted for various brake conditions at the following GVWs: 60,000, 80,000, 91,000, 97,000, 106,000, and 116,000 lb. The 80,000-lb GVWs included both balanced and unbalanced loads. The condition of the braking system was also varied. To introduce these defects, brakes (none, forward drive axle, or rear trailer axle) were made inoperative. In addition to the stopping tests, performance-based brake tests were conducted for the various loading and brake conditions. Analysis of the stopping test data showed the stopping distance to increase with load (as expected) and also showed that more braking force was generated by the drive axle brakes than the trailer axle brakes. The constant-pressure stopping test data

  6. Automotive Brake Systems.

    ERIC Educational Resources Information Center

    Marine Corps Inst., Washington, DC.

    This correspondence course, orginally developed for the Marine Corps, is designed to provide mechanics with an understanding of the basic operations of automotive brake systems on military vehicles. The course contains four study units covering hydraulic brakes, air brakes, power brakes, and auxiliary brake systems. A troubleshooting guide for…

  7. 49 CFR 571.121 - Standard No. 121; Air brake systems.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 6 2012-10-01 2012-10-01 false Standard No. 121; Air brake systems. 571.121 Section 571.121 Transportation Other Regulations Relating to Transportation (Continued) NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION FEDERAL MOTOR VEHICLE SAFETY STANDARDS Federal Motor Vehicle Safety Standards §...

  8. 49 CFR 571.121 - Standard No. 121; Air brake systems.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 6 2014-10-01 2014-10-01 false Standard No. 121; Air brake systems. 571.121 Section 571.121 Transportation Other Regulations Relating to Transportation (Continued) NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION FEDERAL MOTOR VEHICLE SAFETY STANDARDS Federal Motor Vehicle Safety Standards §...

  9. 49 CFR 571.121 - Standard No. 121; Air brake systems.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 6 2013-10-01 2013-10-01 false Standard No. 121; Air brake systems. 571.121 Section 571.121 Transportation Other Regulations Relating to Transportation (Continued) NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION FEDERAL MOTOR VEHICLE SAFETY STANDARDS Federal Motor Vehicle Safety Standards §...

  10. 49 CFR 232.207 - Class IA brake tests-1,000-mile inspection.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Class IA brake tests-1,000-mile inspection. 232.207 Section 232.207 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRAKE SYSTEM SAFETY STANDARDS FOR FREIGHT AND OTHER NON-PASSENGER TRAINS AND...

  11. Compositions, Functions, and Testing of Friction Brake Materials and Their Additives

    SciTech Connect

    Blau, PJ

    2001-10-22

    The purpose of this report is to present a survey of commercial brake materials and additives, and to indicate their typical properties and functions, especially as regards their use in heavy trucks. Most truck pad and shoe materials described here were designed to wear against cast iron. Brake material test methods are also briefly described. This report does not address issues associated with the fabrication and manufacturing of brake materials. Since there are literally thousands of brake material additives, and their combinations are nearly limitless, it is impractical to list them all here. Rather, an attempt has been made to capture the primary constituents and their functions. An Appendix contains thermo-physical properties of some current and potential brake materials.

  12. Air-braked cycle ergometers: validity of the correction factor for barometric pressure.

    PubMed

    Finn, J P; Maxwell, B F; Withers, R T

    2000-10-01

    Barometric pressure exerts by far the greatest influence of the three environmental factors (barometric pressure, temperature and humidity) on power outputs from air-braked ergometers. The barometric pressure correction factor for power outputs from air-braked ergometers is in widespread use but apparently has never been empirically validated. Our experiment validated this correction factor by calibrating two air-braked cycle ergometers in a hypobaric chamber using a dynamic calibration rig. The results showed that if the power output correction for changes in air resistance at barometric pressures corresponding to altitudes of 38, 600, 1,200 and 1,800 m above mean sea level were applied, then the coefficients of variation were 0.8-1.9% over the range of 160-1,597 W. The overall mean error was 3.0 % but this included up to 0.73 % for the propagated error that was associated with errors in the measurement of: a) temperature b) relative humidity c) barometric pressure d) force, distance and angular velocity by the dynamic calibration rig. The overall mean error therefore approximated the +/- 2.0% of true load that was specified by the Laboratory Standards Assistance Scheme of the Australian Sports Commission. The validity of the correction factor for barometric pressure on power output was therefore demonstrated over the altitude range of 38-1,800 m. PMID:11071051

  13. Laboratory testing of airborne brake wear particle emissions using a dynamometer system under urban city driving cycles

    NASA Astrophysics Data System (ADS)

    Hagino, Hiroyuki; Oyama, Motoaki; Sasaki, Sousuke

    2016-04-01

    To measure driving-distance-based mass emission factors for airborne brake wear particulate matter (PM; i.e., brake wear particles) related to the non-asbestos organic friction of brake assembly materials (pads and lining), and to characterize the components of brake wear particles, a brake wear dynamometer with a constant-volume sampling system was developed. Only a limited number of studies have investigated brake emissions under urban city driving cycles that correspond to the tailpipe emission test (i.e., JC08 or JE05 mode of Japanese tailpipe emission test cycles). The tests were performed using two passenger cars and one middle-class truck. The observed airborne brake wear particle emissions ranged from 0.04 to 1.4 mg/km/vehicle for PM10 (particles up to 10 μm (in size), and from 0.04 to 1.2 mg/km/vehicle for PM2.5. The proportion of brake wear debris emitted as airborne brake wear particles was 2-21% of the mass of wear. Oxygenated carbonaceous components were included in the airborne PM but not in the original friction material, which indicates that changes in carbon composition occurred during the abrasion process. Furthermore, this study identified the key tracers of brake wear particles (e.g., Fe, Cu, Ba, and Sb) at emission levels comparable to traffic-related atmospheric environments.

  14. 49 CFR 232.205 - Class I brake test-initial terminal inspection.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... AND OTHER NON-PASSENGER TRAINS AND EQUIPMENT; END-OF-TRAIN DEVICES Inspection and Testing Requirements § 232.205 Class I brake test-initial terminal inspection. (a) Each train and each car in the train shall... defined in § 232.5, at the following points: (1) The location where the train is originally...

  15. Atmospheric testing of wind turbine trailing edge aerodynamic brakes

    SciTech Connect

    Miller, L.S.; Migliore, P.G.; Quandt, G.A.

    1997-12-31

    An experimental investigation was conducted using an instrumented horizontal-axis wind turbine that incorporated variable span trailing-edge aerodynamic brakes. A primary goal was to directly compare study results with (infinite-span) wind tunnel data and to provide information on how to account for device span effects during turbine design or analysis. Comprehensive measurements were utilized to define effective changes in the aerodynamic coefficients, as a function of angle of attack and control deflection, for three device spans and configurations. Differences in the lift and drag behavior are most pronounced near stall and for device spans of less than 15%. Drag performance is affected only minimally (<70%) for 15% or larger span devices. Interestingly, aerodynamic controls with characteristic vents or openings appear most affected by span reductions and three-dimensional flow.

  16. 49 CFR 229.27 - Annual tests.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... supply line to the air brake system shall be cleaned, repaired, or replaced. (2) Brake cylinder relay... portions in the air brake system (including related dirt collectors and filters) shall be cleaned, repaired... record of the parts of the air brake system that are cleaned, repaired, and tested shall be kept in...

  17. Test Results for Rotordynamic Coefficients of the SSME HPOTP Turbine Interstage Seal with Two Swirl Brakes

    NASA Technical Reports Server (NTRS)

    Childs, Dara W.; Baskharone, Erian; Ramsey, Christopher

    1991-01-01

    Test results are presented for the HPOTP Turbine Interstage Seal with both the current and an alternate, aerodynamically designed, swirl brake. Tests were conducted at speeds out to 16,000 rpm, supply pressures up to 18.3 bars, and the following three inlet tangential velocity conditions: (1) no preswirl; (2) intermediate preswirl in the direction of rotation; and (3) high preswirl in the direction of rotation. The back pressure can be controlled independently and was varied to yield the following four pressure ratios: 0.4, 0.45, 0.56, and 0.67. The central and simplest conclusion to be obtained from the test series is that the alternate swirl brake consistently outperforms the current swirl brake in terms of stability performance. The alternate swirl brake's whirl frequency ratio was generally about one half or less than corresponding values for the current design. In many cases, the alternate design yielded negative whirl frequency ratio values in comparison to positive values for the current design. The alternate design can be directly substituted into the space currently occupied by the current design. There is no change in leakage performance.

  18. Test results for rotordynamic coefficients of the SSME HPOTP Turbine Interstage Seal with two swirl brakes

    NASA Technical Reports Server (NTRS)

    Childs, D. W.; Baskharone, Erian; Ramsey, Christopher

    1990-01-01

    Test results are presented for the HPOTP Turbine Interstage Seal with both the current and an alternate, aerodynamically designed, swirl brake. Tests were conducted at speeds out to 16,000 rpm, supply pressures up to 18.3 bars, and the following three inlet-tangential-velocity conditions: (1) no preswirl, (2) intermediate preswirl in the direction of rotation, and (3) high preswirl in the direction of rotation. The back pressure can be controlled independently and was varied to yield the following four pressure ratios: 0.4, 0.45, 0.56, and 0.67. The central and simplest conclusion to be obtained from the test series is that the alternate swirl brake consistently outperforms the current swirl brake in terms of stability performance. The alternate swirl-brake's whirl-frequency ratio was generally about one-half or less than corresponding values for the current design. In many cases, the alternate design yielded negative whirl-frequency-ratio values in comparison to positive values for the current design. The alternate design can be directly substituted into the space currently occupied by the current design. There is no change in leakage performance.

  19. Sensor configuration and test for fault diagnoses of subway braking system based on signed digraph method

    NASA Astrophysics Data System (ADS)

    Zuo, Jianyong; Chen, Zhongkai

    2014-05-01

    Fault diagnosis of various systems on rolling stock has drawn the attention of many researchers. However, obtaining an optimized sensor set of these systems, which is a prerequisite for fault diagnosis, remains a major challenge. Available literature suggests that the configuration of sensors in these systems is presently dependent on the knowledge and engineering experiences of designers, which may lead to insufficient or redundant development of various sensors. In this paper, the optimization of sensor sets is addressed by using the signed digraph (SDG) method. The method is modified for use in braking systems by the introduction of an effect-function method to replace the traditional quantitative methods. Two criteria are adopted to evaluate the capability of the sensor sets, namely, observability and resolution. The sensors configuration method of braking system is proposed. It consists of generating bipartite graphs from SDG models and then solving the set cover problem using a greedy algorithm. To demonstrate the improvement, the sensor configuration of the HP2008 braking system is investigated and fault diagnosis on a test bench is performed. The test results show that SDG algorithm can improve single-fault resolution from 6 faults to 10 faults, and with additional four brake cylinder pressure (BCP) sensors it can cover up to 67 double faults which were not considered by traditional fault diagnosis system. SDG methods are suitable for reducing redundant sensors and that the sensor sets thereby obtained are capable of detecting typical faults, such as the failure of a release valve. This study investigates the formal extension of the SDG method to the sensor configuration of braking system, as well as the adaptation supported by the effect-function method.

  20. Quantification of brake creep groan in vehicle tests and its relation with stick-slip obtained in laboratory tests

    NASA Astrophysics Data System (ADS)

    Neis, P. D.; Ferreira, N. F.; Poletto, J. C.; Matozo, L. T.; Masotti, D.

    2016-05-01

    This paper describes the development of a methodology for assessing and correlating stick-slip and brake creep groan. For doing that, results of tribotests are compared to data obtained in vehicle tests. A low velocity and a linear reduction in normal force were set for the tribotests. The vehicle tests consisted of subjecting a sport utility vehicle to three different ramp slopes. Creep groan events were measured by accelerometers placed on the brake calipers. The root mean square of the acceleration signal (QRMS parameter) was shown to be able to measure the creep groan severity resulting from the vehicle tests. Differences in QRMS were observed between front-rear and left-right wheels for all tested materials. Frequency spectrum analysis of the acceleration revealed that the wheel side and material type do not cause any significant shift in the creep groan frequency. QRMS measured in the vehicle tests presented good correlation with slip power (SP) summation. For this reason, SP summation may represent the "creep groan propensity" of brake materials. Thus, the proposed tribotest method can be utilized to predict the creep groan severity of brake materials in service.

  1. Elemental composition of current automotive braking materials and derived air emission factors

    NASA Astrophysics Data System (ADS)

    Hulskotte, J. H. J.; Roskam, G. D.; Denier van der Gon, H. A. C.

    2014-12-01

    Wear-related PM emissions are an important constituent of total PM emissions from road transport. Due to ongoing (further) exhaust emission reduction wear emissions may become the dominant PM source from road transport in the near future. The chemical composition of the wear emissions is crucial information to assess the potential health relevance of these PM emissions. Here we provide an elemental composition profile of brake wear emissions as used in the Netherlands in 2012. In total, 65 spent brake pads and 15 brake discs were collected in car maintenance shops from in-use personal cars vehicles and analyzed with XRF for their metal composition (Fe, Cu, Zn, Sn, Al, Si, Zr, Ti, Sb, Cr, Mo, Mn, V, Ni, Bi, W, P, Pb and Co). Since car, engine and safety regulations are not nationally determined but controlled by European legislation the resulting profiles will be representative for the European personal car fleet. The brake pads contained Fe and Cu as the dominant metals but their ratio varied considerably, other relatively important metals were Sn, Zn and Sb. Overall a rather robust picture emerged with Fe, Cu, Zn and Sn together making up about 80-90% of the metals present in brake pads. Because the XRF did not give information on the contents of other material such as carbon, oxygen and sulphur, a representative selection of 9 brake pads was further analyzed by ICP-MS and a carbon and sulphur analyzer. The brake pads contained about 50% of non-metal material (26% C, 3% S and the remainder mostly oxygen and some magnesium). Based on our measurements, the average brake pad profile contained 20% Fe, 10% Cu, 4% Zn and 3% Sn as the dominant metals. The brake discs consisted almost entirely of metal with iron being the dominant metal (>95%) and only traces of other metals (<1% for individual metals). Non-metal components in the discs were 2-3% Silicon and, according to literature, ∼3% carbon. The robust ratio between Fe and Cu as found on kerbsides has been used to

  2. Airborne brake wear debris: size distributions, composition, and a comparison of dynamometer and vehicle tests.

    PubMed

    Sanders, Paul G; Xu, Ning; Dalka, Tom M; Maricq, M Matti

    2003-09-15

    Particle size distributions of light-duty vehicle brake wear debris are reported with careful attention paid to avoid sampling biases. Electrical low-pressure impactor and micro-orifice uniform deposit impactor measurements yield consistent size distributions, and the net particulate matter mass from each method is in good agreement with gravimetric filter measurements. The mass mean diameter of wear debris from braking events representative of urban driving is 6 microm, and the number-weighted mean is 1-2 microm for three currently used classes of lining materials: low metallic, semimetallic, and non-asbestos organic (NAO). In contrast, the wear rates are very material dependent, both in number and mass of particles, with 3-4 times higher emissions observed from the low metallic linings as compared to the semimetallic and NAO linings. Wind tunnel and test track measurements demonstrate the appearance of micron size particles that correlate with braking events, with approximately 50% of the wear debris being airborne for the test vehicle in this study. Elemental analysis of the wear debris reveals a consistent presence of the elements Fe, Cu, and Ba in both dynamometer and test track samples. PMID:14524436

  3. The design of aircraft brake systems, employing cooling to increase brake life

    NASA Technical Reports Server (NTRS)

    Scaringe, R. P.; Ho, T. L.; Peterson, M. B.

    1975-01-01

    A research program was initiated to determine the feasibility of using cooling to increase brake life. An air cooling scheme was proposed, constructed and tested with various designs. Straight and curved slotting of the friction material was tested. A water cooling technique, similar to the air cooling procedure, was evaluated on a curved slotted rotor. Also investigated was the possibility of using a phase-change material within the rotor to absorb heat during braking. Various phase-changing materials were tabulated and a 50%, (by weight) LiF - BeF2 mixing was chosen. It was shown that corrosion was not a problem with this mixture. A preliminary design was evaluated on an actual brake. Results showed that significant improvements in lowering the surface temperature of the brake occurred when air or water cooling was used in conjunction with curved slotted rotors.

  4. Mechanical testing and modelling of carbon-carbon composites for aircraft disc brakes

    NASA Astrophysics Data System (ADS)

    Bradley, Luke R.

    The objective of this study is to improve the understanding of the stress distributions and failure mechanisms experienced by carbon-carbon composite aircraft brake discs using finite element (FE) analyses. The project has been carried out in association with Dunlop Aerospace as an EPSRC CASE studentship. It therefore focuses on the carbon-carbon composite brake disc material produced by Dunlop Aerospace, although it is envisaged that the approach will have broader applications for modelling and mechanical testing of carbon-carbon composites in general. The disc brake material is a laminated carbon-carbon composite comprised of poly(acrylonitrile) (PAN) derived carbon fibres in a chemical vapour infiltration (CVI) deposited matrix, in which the reinforcement is present in both continuous fibre and chopped fibre forms. To pave the way for the finite element analysis, a comprehensive study of the mechanical properties of the carbon-carbon composite material was carried out. This focused largely, but not entirely, on model composite materials formulated using structural elements of the disc brake material. The strengths and moduli of these materials were measured in tension, compression and shear in several orientations. It was found that the stress-strain behaviour of the materials were linear in directions where there was some continuous fibre reinforcement, but non-linear when this was not the case. In all orientations, some degree of non-linearity was observed in the shear stress-strain response of the materials. However, this non-linearity was generally not large enough to pose a problem for the estimation of elastic moduli. Evidence was found for negative Poisson's ratio behaviour in some orientations of the material in tension. Additionally, the through-thickness properties of the composite, including interlaminar shear strength, were shown to be positively related to bulk density. The in-plane properties were mostly unrelated to bulk density over the range of

  5. 49 CFR 393.44 - Front brake lines, protection.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 5 2010-10-01 2010-10-01 false Front brake lines, protection. 393.44 Section 393... ACCESSORIES NECESSARY FOR SAFE OPERATION Brakes § 393.44 Front brake lines, protection. On every bus, if equipped with air brakes, the braking system shall be so constructed that in the event any brake line...

  6. 49 CFR 393.44 - Front brake lines, protection.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 5 2012-10-01 2012-10-01 false Front brake lines, protection. 393.44 Section 393... ACCESSORIES NECESSARY FOR SAFE OPERATION Brakes § 393.44 Front brake lines, protection. On every bus, if equipped with air brakes, the braking system shall be so constructed that in the event any brake line...

  7. 49 CFR 393.44 - Front brake lines, protection.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 5 2013-10-01 2013-10-01 false Front brake lines, protection. 393.44 Section 393... ACCESSORIES NECESSARY FOR SAFE OPERATION Brakes § 393.44 Front brake lines, protection. On every bus, if equipped with air brakes, the braking system shall be so constructed that in the event any brake line...

  8. 49 CFR 393.44 - Front brake lines, protection.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 5 2014-10-01 2014-10-01 false Front brake lines, protection. 393.44 Section 393... ACCESSORIES NECESSARY FOR SAFE OPERATION Brakes § 393.44 Front brake lines, protection. On every bus, if equipped with air brakes, the braking system shall be so constructed that in the event any brake line...

  9. 49 CFR 393.44 - Front brake lines, protection.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 5 2011-10-01 2011-10-01 false Front brake lines, protection. 393.44 Section 393... ACCESSORIES NECESSARY FOR SAFE OPERATION Brakes § 393.44 Front brake lines, protection. On every bus, if equipped with air brakes, the braking system shall be so constructed that in the event any brake line...

  10. 49 CFR 238.231 - Brake system.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... location so that nothing may interfere with the air flow to brake cylinder and inspected pursuant to the... reservoirs must be voided of all compressed air. When cutout cocks are provided in brake cylinder...

  11. 49 CFR 238.231 - Brake system.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... location so that nothing may interfere with the air flow to brake cylinder and inspected pursuant to the... reservoirs must be voided of all compressed air. When cutout cocks are provided in brake cylinder...

  12. 75 FR 51521 - Federal Motor Vehicle Safety Standards; Air Brake Systems; Technical Report on the Effectiveness...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-20

    ... Expenses for the Anti-Lock Brake System and Underride Guard for Tractors and Trailers (74 FR 18803... DOT's complete Privacy Act Statement in the Federal Register published on April 11, 2000 (65 FR 19477... crash is not important. Rather, external factors of urbanization, road speed, and ambient lighting...

  13. Air gun test evaluation

    SciTech Connect

    Carleton, J.J. II; Fox, L.; Rudy, C.R.

    1992-01-15

    A mechanical shock testing apparatus is used for testing the response of components subject to large accelerations in hostile environments. The test acceleration is provided by the impact of a bullet against a plate on which the component to be tested is mounted. This report describes a series of experiments that were performed to determine the dependence of the air gun test apparatus performance on incremental changes in the hardware configurations, changes in the pressure used to drive the bullet, and different accelerometers. The effect of variation of these experimental factors on the measured acceleration was determined using a Taguchi screening experimental design. Experimental settings were determined that can be used to operate the tester with a measured output within acceleration specifications.

  14. Wheel brakes and their application to aircraft

    NASA Technical Reports Server (NTRS)

    Dowty, G H

    1928-01-01

    The advantages to be gained from braking have not been ignored, and in the search for a suitable method many schemes have been suggested and tried. Some of the methods discussed in this paper include: 1) increasing the height of the landing gear; 2) air brakes of various forms; 3) sprags on tail skid and axle; and 4) wheel brakes. This report focuses on the design of wheel brakes and wheel brake controls.

  15. 49 CFR 393.43 - Breakaway and emergency braking.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... towing vehicle will be capable of stopping the towing vehicle. For air braked towing units, the tractor... or truck tractor equipped with air brakes, when used for towing other vehicles equipped with air..., separate. (c) Emergency brake requirements, vacuum brakes. Every truck tractor and truck when used...

  16. Shuttle Rudder/Speed Brake Power Drive Unit (PDU) Gear Scuffing Tests With Flight Gears

    NASA Technical Reports Server (NTRS)

    Proctor, Margaret P.; Oswald, Fred B.; Krants, Timothy L.

    2005-01-01

    Scuffing-like damage has been found on the tooth surfaces of gears 5 and 6 of the NASA space shuttle rudder/speed brake power drive unit (PDU) number 2 after the occurrence of a transient back-driving event in flight. Tests were conducted using a pair of unused spare flight gears in a bench test at operating conditions up to 2866 rpm and 1144 in.-lb at the input ring gear and 14,000 rpm and 234 in.-lb at the output pinion gear, corresponding to a power level of 52 hp. This test condition exceeds the maximum estimated conditions expected in a backdriving event thought to produce the scuffing damage. Some wear marks were produced, but they were much less severe than the scuffing damaged produced during shuttle flight. Failure to produce scuff damage like that found on the shuttle may be due to geometrical variations between the scuffed gears and the gears tested herein, more severe operating conditions during the flight that produced the scuff than estimated, the order of the test procedures, the use of new hydraulic oil, differences between the dynamic response of the flight gearbox and the bench-test gearbox, or a combination of these. This report documents the test gears, apparatus, and procedures, summarizes the test results, and includes a discussion of the findings, conclusions, and recommendations.

  17. A Test of the Tau-Dot Hypothesis of Braking Control in the Real World

    ERIC Educational Resources Information Center

    Rock, Paul B.; Harris, Mike G.; Yates, Tim

    2006-01-01

    A controlled experiment used instrumented vehicles in a real-world driving task to compare D. N. Lee's (1976) tau-dot hypothesis of braking control with an alternative based on the direct estimation and control of ideal deceleration (T. Yates, M. Harris, & P. Rock, 2004). Drivers braked to stop as closely as possible to a visual target from…

  18. Typical pedestrian accident scenarios for the development of autonomous emergency braking test protocols.

    PubMed

    Lenard, James; Badea-Romero, Alexandro; Danton, Russell

    2014-12-01

    An increasing proportion of new vehicles are being fitted with autonomous emergency braking systems. It is difficult for consumers to judge the effectiveness of these safety systems for individual models unless their performance is evaluated through track testing under controlled conditions. This paper aimed to contribute to the development of relevant test conditions by describing typical circumstances of pedestrian accidents. Cluster analysis was applied to two large British databases and both highlighted an urban scenario in daylight and fine weather where a small pedestrian walks across the road, especially from the near kerb, in clear view of a driver who is travelling straight ahead. For each dataset a main test configuration was defined to represent the conditions of the most common accident scenario along with test variations to reflect the characteristics of less common accident scenarios. Some of the variations pertaining to less common accident circumstances or to a minority of casualties in these scenarios were proposed as optional or supplementary test elements for an outstanding performance rating. Many considerations are incorporated into the final design and implementation of an actual testing regime, such as cost and the state of development of technology; only the representation of accident data lay within the scope of this paper. It would be desirable to ascertain the wider representativeness of the results by analysing accident data from other countries in a similar manner. PMID:25180785

  19. Integrated assessment of pedestrian head impact protection in testing secondary safety and autonomous emergency braking.

    PubMed

    Searson, D J; Anderson, R W G; Hutchinson, T P

    2014-02-01

    Pedestrian impact testing is used to provide information to the public about the relative level of protection provided by different vehicles to a struck pedestrian. Autonomous Emergency Braking (AEB) is a relatively new technology that aims to reduce the impact speed of such crashes. It is expected that vehicles with AEB will pose less harm to pedestrians, and that the benefit will come about through reductions in the number of collisions and a change in the severity of impacts that will still occur. In this paper, an integration of the assessment of AEB performance and impact performance is proposed based on average injury risk. Average injury risk is calculated using the result of an impact test and a previously published distribution of real world crash speeds. A second published speed distribution is used that accounts for the effects of AEB, and reduced average risks are implied. This principle allows the effects of AEB systems and secondary safety performance to be integrated into a single measure of safety. The results are used to examine the effect of AEB on Euro NCAP and ANCAP assessments using previously published results on the likely effect of AEB. The results show that, given certain assumptions about AEB performance, the addition of AEB is approximately the equivalent of increasing Euro NCAP test performance by one band, which corresponds to an increase in the score of 25% of the maximum. PMID:24246294

  20. Gravity brake

    DOEpatents

    Lujan, Richard E.

    2001-01-01

    A mechanical gravity brake that prevents hoisted loads within a shaft from free-falling when a loss of hoisting force occurs. A loss of hoist lifting force may occur in a number of situations, for example if a hoist cable were to break, the brakes were to fail on a winch, or the hoist mechanism itself were to fail. Under normal hoisting conditions, the gravity brake of the invention is subject to an upward lifting force from the hoist and a downward pulling force from a suspended load. If the lifting force should suddenly cease, the loss of differential forces on the gravity brake in free-fall is translated to extend a set of brakes against the walls of the shaft to stop the free fall descent of the gravity brake and attached load.

  1. Better Brakes

    NASA Technical Reports Server (NTRS)

    1976-01-01

    Through continuing studies on high-temperature space materials useful for better brake linings, Bendix Corporation worked with Ames Research Center to develop a novel composite. This team worked to fabricate several combinations of composite materials and evaluated results. The one selected increases wear rates and lowers costs. It exhibits constant coefficient of friction at temperatures as high as 650 degrees Fahrenheit, a region where conventional brake linings fade markedly. Other suitable markets include brakes for trucks and industrial equipment such as overhead cranes and hoists. Afterwards brake linings could find successful application in passenger cars.

  2. Air emissions testing

    SciTech Connect

    Johnson, L.D.

    1993-01-01

    The article presents a brief overview of air emission sampling methods and analysis procedures related to stationary sources such as incinerators, power plants, and industrial boilers. It is intended primarily for the laboratory chemist or manager who is familiar with samples and methods associated with water or waste sources, but not with those associated with air and stack gas emissions.

  3. A test-based method for the assessment of pre-crash warning and braking systems.

    PubMed

    Bálint, András; Fagerlind, Helen; Kullgren, Anders

    2013-10-01

    In this paper, a test-based assessment method for pre-crash warning and braking systems is presented where the effectiveness of a system is measured by its ability to reduce the number of injuries of a given type or severity in car-to-car rear-end collisions. Injuries with whiplash symptoms lasting longer than 1 month and MAIS2+ injuries in both vehicles involved in the crash are considered in the assessment. The injury reduction resulting from the impact speed reduction due to a pre-crash system is estimated using a method which has its roots in the dose-response model. Human-machine interaction is also taken into account in the assessment. The results reflect the self-protection as well as the partner-protection performance of a pre-crash system in the striking vehicle in rear-end collisions and enable a comparison between two or more systems. It is also shown how the method may be used to assess the importance of warning as part of a pre-crash system. PMID:23792618

  4. Braking system

    DOEpatents

    Norgren, D.U.

    1982-09-23

    A balanced braking system comprising a plurality of braking assemblies located about a member to be braked. Each of the braking assemblies consists of a spring biased piston of a first material fitted into a body of a different material which has a greater contraction upon cooling than the piston material. The piston is provided with a recessed head portion over which is positioned a diaphragm and forming a space therebetween to which is connected a pressurized fluid supply. The diaphragm is controlled by the fluid in the space to contact or withdraw from the member to be braked. A cooling means causes the body within which the piston is fitted to contract more than the piston, producing a tight shrink fit therebetween. The braking system is particularly applicable for selectively braking an arbor of an electron microscope which immobilizes, for example, a vertically adjustable low temperature specimen holder during observation. The system provides balanced braking forces which can be easily removed and re-established with minimal disturbance to arbor location.

  5. 49 CFR 236.712 - Brake pipe.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Brake pipe. 236.712 Section 236.712 Transportation... OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Definitions § 236.712 Brake pipe. A pipe running from the engineman's brake valve through the train, used for the transmission of air...

  6. 49 CFR 236.712 - Brake pipe.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Brake pipe. 236.712 Section 236.712 Transportation... OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Definitions § 236.712 Brake pipe. A pipe running from the engineman's brake valve through the train, used for the transmission of air...

  7. 49 CFR 236.712 - Brake pipe.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Brake pipe. 236.712 Section 236.712 Transportation... OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Definitions § 236.712 Brake pipe. A pipe running from the engineman's brake valve through the train, used for the transmission of air...

  8. 49 CFR 236.712 - Brake pipe.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Brake pipe. 236.712 Section 236.712 Transportation... OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Definitions § 236.712 Brake pipe. A pipe running from the engineman's brake valve through the train, used for the transmission of air...

  9. Magnetostrictive Brake

    NASA Technical Reports Server (NTRS)

    Diftler, Myron A.; Hulse, Aaron

    2010-01-01

    A magnetostrictive brake has been designed as a more energy-efficient alternative to a magnetic fail-safe brake in a robot. (In the specific application, failsafe signifies that the brake is normally engaged; that is, power must be supplied to allow free rotation.) The magnetic failsafe brake must be supplied with about 8 W of electric power to initiate and maintain disengagement. In contrast, the magnetostrictive brake, which would have about the same dimensions and the same torque rating as those of the magnetic fail-safe brake, would demand only about 2 W of power for disengagement. The brake (see figure) would include a stationary base plate and a hub mounted on the base plate. Two solenoid assemblies would be mounted in diametrically opposed recesses in the hub. The cores of the solenoids would be made of the magnetostrictive alloy Terfenol-D or equivalent. The rotating part of the brake would be a ring-and spring- disk subassembly. By means of leaf springs not shown in the figure, this subassembly would be coupled with the shaft that the brake is meant to restrain. With no power supplied to the solenoids, a permanent magnet would pull axially on a stepped disk and on a shelf in the hub, causing the ring to be squeezed axially between the stepped disk and the hub. The friction associated with this axial squeeze would effect the braking action. Supplying electric power to the solenoids would cause the magnetostrictive cylinders to push radially inward against a set of wedges that would be in axial contact with the stepped disk. The wedges would convert the radial magnetostrictive strain to a multiplied axial displacement of the stepped disk. This axial displacement would be just large enough to lift the stepped disk, against the permanent magnetic force, out of contact with the ring. The ring would then be free to turn because it would no longer be squeezed axially between the stepped disk and the hub.

  10. Testing for Air Pollution.

    ERIC Educational Resources Information Center

    Dunbar, Artice

    Three experiments are presented in this Science Study Aid to provide the teacher with some fundamental air pollution activities. The first experiment involved particulates, the second deals with microorganisms, and the third looks at gases in the atmosphere. Each activity outlines introductory information, objectives, materials required, procedure…

  11. Determining the frequency of asbestos use in automotive brakes from a fleet of on-road California vehicles.

    PubMed

    De Vita, Joseph; Wall, Stephen; Wagner, Jeff; Wang, Zhong-Min; Rao, Leela E

    2012-02-01

    Asbestos is a known human carcinogen, and recent regulation in California limits asbestiform fibers in brakes to trace levels beginning in 2014, although there is no corresponding federal requirement. In order to gauge the current prevalence of asbestos use in automotive brake applications, the California Air Resources Board tested brake linings from 137 light- and medium-duty vehicles and 54 heavy-duty vehicles. Only about 3% of the light- and medium-duty vehicle brake linings contained chrysotile asbestos. All of those brake linings were drum-type shoes, which are generally being phased out. No asbestos was found in low mileage vehicles presumed to have their original stock linings from the vehicle manufacturer. Additionally, no asbestos was found in the heavy-duty vehicle brake shoe linings sampled. Given the small percentage of vehicle brake linings with asbestos observed, it appears that the prior federal ban that was subsequently overturned, in combination with a threat of litigation, has reduced asbestos use in brake linings. However, our study was limited in scope and without a national ban, the current and future prevalence of asbestos in brakes is uncertain, suggesting the need for continued monitoring of materials released as toxic air contaminants in normal braking operations. PMID:22191788

  12. Advanced air revitalization system testing

    NASA Technical Reports Server (NTRS)

    Heppner, D. B.; Hallick, T. M.; Schubert, F. H.

    1983-01-01

    A previously developed experimental air revitalization system was tested cyclically and parametrically. One-button startup without manual interventions; extension by 1350 hours of tests with the system; capability for varying process air carbon dioxide partial pressure and humidity and coolant source for simulation of realistic space vehicle interfaces; dynamic system performance response on the interaction of the electrochemical depolarized carbon dioxide concentrator, the Sabatier carbon dioxide reduction subsystem, and the static feed water electrolysis oxygen generation subsystem, the carbon dioxide concentrator module with unitized core technology for the liquid cooled cell; and a preliminary design for a regenerative air revitalization system for the space station are discussed.

  13. Performance and aerodynamic braking of a horizontal-axis wind turbine from small-scale wind tunnel tests

    SciTech Connect

    Cao, H.V.; Wentz, W.H. Jr.

    1987-07-01

    Wind tunnel tests of three 20-inch diameter, zero-twist, zero-pitch wind turbine rotor models have been conducted in the WSU 7' x 10' wind tunnel to determine the performance of such rotors with NACA 23024 and NACA 64/sub 3/-621 airfoil sections. Aerodynamic braking characteristics of a 38 percent span, 30 percent chord, vented aileron configuration were measured on the NACA 23024 rotor. Surface flow patterns were observed using fluorescent mini-tufts attached to the suction side of the rotor blades. Experimental results with and without ailerons are compared to predictions using airfoil section data and a momentum performance code. Results of the performance studies show that the 64/sub 3/-621 rotor produces higher peak power than the 23024 rotor for a given rotor speed. Analytical studies, however, indicate that the 23024 should produce higher power. Transition strip experiments show that the 23024 rotor is much more sensitive to roughness than the 64/sub 3/-621 rotor. These trends agree with analytical predictions. Results of the aileron tests show that this aileron, when deflected, produces a braking torque at all tip-speed ratios. In free-wheeling coastdowns the rotor blade stopped, then rotated backward at a tip-speed ratio of -0.6. Results of the tuft studies indicate that substantial spanwise flow develops as blade stall occurs at low tip-speed ratios.

  14. Performance and aerodynamic braking of a horizontal-axis wind turbine from small-scale wind tunnel tests

    NASA Technical Reports Server (NTRS)

    Cao, H. V.; Wentz, W. H., Jr.

    1987-01-01

    Wind tunnel tests of three 20" diameter, zero twist, zero pitch wind turbine rotor models were conducted in a 7' x 10' wind tunnel to determine the performance of such rotors with NACA 23024 and NACA 64 sub 3-621 airfoil sections. Aerodynamic braking characteristics of a 38% span, 30% chord, vented aileron configuration were measured on the NACA 23024 rotor. Surface flow patterns were observed using fluorescent mini-tufts attached to the suction side of the rotor blades. Experimental results with and without ailerons are compared to predictions using airfoil section data and a momentum performance code. Results of the performance studies show that the 64 sub 3-621 rotor produces higher peak power than the 23024 rotor for a given rotor speed. Analytical studies, however, indicate that the 23024 should produce higher power. Transition strip experiments show that the 23024 rotor is much more sensitive to roughness than the 64 sub 3-621 rotor. These trends agree with analytical predictions. Results of the aileron test show that this aileron, when deflected, produces a braking torque at all tip speed ratios. In free wheeling coastdowns the rotor blade stopped, then rotated backward at a tip speed ratio of -0.6.

  15. Regression Test on the Rotational Speed between Two Loads as the Preparation for Braking System

    NASA Astrophysics Data System (ADS)

    Purwanti, B. S. R.; Yusivar, F.; K, I. Garniwa M.

    2013-04-01

    This paper is preparing the mathematic model of braking control, continuously of determination the error (e), delta error (de) of speed reduction [9]. Load-1 and Load-2 are driven by an electric motor located on the same shaft. Both loads are driven clock wise (CW), counter clock wise (CCW) by an asynchronous three-phase motor (M3). The mass of each load is also differentiated to simulate slip phenomena. Rotational speed of M3 is equal to Load-1, detected by Sensor-1, while speed rotation of Load-2 is detected by Sensor-2. The rotation for Load-1 and Load-2 can be adjusted on several position Hj (j = 1, 2, 3). Once Load-1 and Load-2 reach a constant speed, current source will be disconnected. Speed reduction from (ω±1475 rpm) to stagnant (ω=0 rpm) on Load-1 and Load-2 is considered time function. Data collected from both load (ω (t)) known as e, de; on each position of Hj. It uses covariance analysis to make sure that both loads are concurrent with each other against time difference. The objective of this research is to determine slip phenomena of speed reduction of each load. The expectations are to generate smoother braking and minimize the time needed when implemented with ANFIS.

  16. BRAKE DEVICE

    DOEpatents

    O'Donnell, T.J.

    1959-03-10

    A brake device is described for utilization in connection with a control rod. The device comprises a pair of parallelogram link mechanisms, a control rod moveable rectilinearly therebetween in opposite directions, and shoes resiliently supported by the mechanism for frictional engagement with the control rod.

  17. Seal-rotordynamic-coefficient Test Results for a Model SSME ATD-HPFTP Turbine Interstage Seal with and Without a Swirl Brake

    NASA Technical Reports Server (NTRS)

    Childs, Dara W.; Ramsey, Christopher

    1991-01-01

    The predictions of Scharrer's (1988) theory for rotordynamic coefficients of labyrinth gas seals were compared with measurements for a model SSME Alternate Turbopump Development High Pressure Fuel Turbopump with and without swirl brakes. Using the test apparatus described by Childs et al., tests were conducted with supply pressures up to 18.3 bars and speeds up to 16,000 rpm. Seal back pressure was controlled to provide four pressure ratios at all supply pressures. No measurable differences in leakage was detected for the seal with and without the swirl brakes. Comparisons of the measurement results for the seal without a swirl brake with the Scharrer theory showed that the theory can be used only to provide design guidelines; systematic differences were observed between theory and experiment due to changes in running speed, supply pressure, and pressure ratio.

  18. Seal-rotordynamic-coefficient test results for a model SSME ATD-HPFTP turbine interstate seal with and without a swirl brake

    NASA Technical Reports Server (NTRS)

    Childs, D. W.; Ramsey, C.

    1991-01-01

    The predictions of Scharrer's (1988) theory for rotordynamic coefficients of labyrinth gas seals were compared with measurements for a model SSME Alternate Turbopump Development High-Pressure Fuel Turbopump with and without swirl brakes. Using the test apparatus described by Childs et al. (1986, 1990), tests were conducted with supply pressures up to 18.3 bars and speeds up to 16,000 rpm. Seal back pressure was controlled to provide four pressure ratios at all supply pressures. No measurable difference in leakage was detected for the seal with and without the swirl brakes. Comparisons of the measurement results for the seal without a swirl brake with the Scharrer theory showed that the theory can be used only to provide design guidelines; systematic differences were observed between theory and experiment due to changes in running speed, supply pressure, and pressure ratio.

  19. 49 CFR 393.48 - Brakes to be operative.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... must not be operable when the brake control application pressure exceeds 85 psig (for vehicles equipped with air brakes) or 85 percent of the maximum system pressure (for vehicles which are not equipped...

  20. Testing Air-Filtering Systems

    PubMed Central

    Songer, Joseph R.; Sullivan, James F.; Hurd, James W.

    1963-01-01

    A procedure was developed for evaluating high-efficiency filters mounted in exhaust ducts at the National Animal Disease Laboratory. An aerosol of the test organism, Escherichia coli B T3 bacteriophage, was generated in a chamber attached to a ceiling exhaust register in concentrations of at least 1000 viable organisms per ft3 of air. Samples were collected from both the pre- and postfilter areas, and the number of organisms per ft3 of air was determined. The efficiency of the filter was calculated from these figures. A total of 269 high-efficiency filters were tested. Of these, 249 had efficiencies of 98% or greater. The remaining 20, with efficiencies of less than 98%, were repaired and retested. No filter was accepted with an efficiency of less than 98%. Images Fig. 2 PMID:14063779

  1. Thermal analysis and temperature characteristics of a braking resistor for high-speed trains for changes in the braking current

    NASA Astrophysics Data System (ADS)

    Lee, Dae-Dong; Kang, Hyun-Il; Shim, Jae-Myung

    2015-09-01

    Electric brake systems are used in high-speed trains to brake trains by converting the kinetic energy of a railway vehicle to electric energy. The electric brake system consists of a regenerative braking system and a dynamic braking system. When the electric energy generated during the dynamic braking process is changed to heat through the braking resistor, the braking resistor can overheat; thus, failures can occur to the motor block. In this paper, a braking resistor for a high-speed train was used to perform thermal analyses and tests, and the results were analyzed. The analyzed data were used to estimate the dependence of the brake currents and the temperature rises on speed changes up to 300 km/h, at which a test could not be performed.

  2. Modelling and validation of magnetorheological brake responses using parametric approach

    NASA Astrophysics Data System (ADS)

    Z, Zainordin A.; A, Abdullah M.; K, Hudha

    2013-12-01

    Magnetorheological brake (MR Brake) is one x-by-wire systems which performs better than conventional brake systems. MR brake consists of a rotating disc that is immersed with Magnetorheological Fluid (MR Fluid) in an enclosure of an electromagnetic coil. The applied magnetic field will increase the yield strength of the MR fluid where this fluid was used to decrease the speed of the rotating shaft. The purpose of this paper is to develop a mathematical model to represent MR brake with a test rig. The MR brake model is developed based on actual torque characteristic which is coupled with motion of a test rig. Next, the experimental are performed using MR brake test rig and obtained three output responses known as angular velocity response, torque response and load displacement response. Furthermore, the MR brake was subjected to various current. Finally, the simulation results of MR brake model are then verified with experimental results.

  3. Preliminary test results of the joint FAA-USAF-NASA runway research program. Part 1: Traction measurements of several runways under wet and dry conditions with a Boeing 727, a diagonal-braked vehicle, and a mu-meter

    NASA Technical Reports Server (NTRS)

    Horne, W. B.; Yager, T. J.; Sleeper, R. K.; Merritt, L. R.

    1977-01-01

    The stopping distance, brake application velocity, and time of brake application were measured for two modern jet transports, along with the NASA diagonal-braked vehicle and the British Mu-Meter on several runways, which when wetted, cover the range of slipperiness likely to be encountered in the United States. Tests were designed to determine if correlation between the aircraft and friction measuring vehicles exists. The test procedure, data reduction techniques, and preliminary test results obtained with the Boeing 727, the Douglas DC-9, and the ground vehicles are given. Time histories of the aircraft test run parameters are included.

  4. 10. "TEST STAND 15, AIR FORCE FLIGHT TEST CENTER." ca. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. "TEST STAND 1-5, AIR FORCE FLIGHT TEST CENTER." ca. 1958. Test Area 1-115. Original is a color print, showing Test Stand 1-5 from below, also showing the superstructure of TS1-4 at left. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Leuhman Ridge near Highways 58 & 395, Boron, Kern County, CA

  5. Recent studies of tire braking performance. [for aircraft

    NASA Technical Reports Server (NTRS)

    Mccarty, J. L.; Leland, T. J. W.

    1973-01-01

    The results from recent studies of some factors affecting tire braking and cornering performance are presented together with a discussion of the possible application of these results to the design of aircraft braking systems. The first part of the paper is concerned with steady-state braking, that is, results from tests conducted at a constant slip ratio or steering angle or both. The second part deals with cyclic braking tests, both single cycle, where brakes are applied at a constant rate until wheel lockup is achieved, and rapid cycling of the brakes under control of a currently operational antiskid system.

  6. Flight testing air-to-air missiles for flutter

    NASA Technical Reports Server (NTRS)

    Kutschinski, C. R.

    1975-01-01

    The philosophy of the design of air-to-air missiles and hence of flight testing them for flutter differs from that of manned aircraft. Primary emphasis is put on analytical and laboratory evaluation of missile susceptibility to aeroelastic and aero-servo-elastic instabilities and uses flight testing for confirmation of the absence of such instabilities. Flight testing for flutter is accomplished by using specially instrumented programmed missiles, air or ground launched with a booster to reach the extreme flight conditions of tactical use, or by using guided missiles with telemetered performance data. The instrumentation and testing techniques are discussed along with the success of recent flight tests.

  7. Experiments with airplane brakes

    NASA Technical Reports Server (NTRS)

    Michael, Franz

    1931-01-01

    This report begins by examining the forces on the brake shoes. For the determination of the load distribution over the shoes it was assumed that the brake linings follow Hooke's law, are neatly fitted and bedded in by wear. The assumption of Hooke's law, that is, the proportionality between compression of the lining and the absorption of force, is fulfilled to a certain extent for the loading, as becomes apparent from the load tests described further on. But there is a material discrepancy at unloading. From the load distribution we merely defined the position of the normal force resultant, while for the rest, the effect of the distribution was disregarded in the comparison of the different shoe dispositions.

  8. PREDICTING RANGES FOR PULSARS' BRAKING INDICES

    SciTech Connect

    Magalhaes, Nadja S.; Miranda, Thaysa A.; Frajuca, Carlos

    2012-08-10

    The theoretical determination of braking indices of pulsars is still an open problem. In this paper we report results of a study concerning such determination based on a modification of the canonical model, which admits that pulsars are rotating magnetic dipoles, and on data from the seven pulsars with known braking indices. In order to test the modified model, we predict ranges for the braking indices of other pulsars.

  9. Rotary Speed Sensor for Antilocking Brakes

    NASA Technical Reports Server (NTRS)

    Berdahl, C. M.

    1986-01-01

    Sensor based on fluidic principles produces negative pressure approximately proportional to rotational speed. Sensor developed as part of antilocking brake system for motorcycles. Uses inlet pressure rather than outlet pressure as braking-control signal, eliminating pressure pulsations caused by pump vanes and ensuring low-noise signal. Sensor is centrifugal air pump turned by one of motorcycle wheels. Air enters pump through orifice plates, and suction taken off through port in pump inlet plenum.

  10. Optimal design of a novel configuration of MR brake with coils placed on the side housings

    NASA Astrophysics Data System (ADS)

    Nguyen, Quoc Hung; Nguyen, Ngoc Diep; Choi, Seung-Bok

    2014-03-01

    It is well known that in design of traditional magneto-rheological brake (MRB), coils are placed on the cylindrical housing of the brake. In this study, a new configuration of MR brake with coils placed on the side housings of the brake is proposed and analyzed. After briefly explaining the operating principle of the proposed configuration, the braking torque of the MR brake is analyze based on Bingham-plastic rheological model of MR fluid. The optimization of the proposed and conventional MR brakes is then performed considering maximum braking torque and mass of the brake. Based on the optimal results, a comparison between the proposed MR brakes and the conventional ones is undertaken. In addition, experimental test of the MR brakes is conducted and the results are presented in order to validate the performance characteristics of the proposed MR brake.

  11. Testing the Patriot air defense weapon system

    NASA Astrophysics Data System (ADS)

    Graham, W. L.; McClay, L. F.

    1983-11-01

    A summary of the overall test program of the Patriot air defense weapon system is presented, including preparations for system integration tests and surveillance tests, with particular emphasis placed on the guidance flight test program. The major components of the system are described, and subsystem tests consisting of static and dynamic plume tests, static propulsion tests, dynamic propulsion test firings, and control system test firings are discussed. A series of system-level preflight guidance tests which consisted of a captive carry flight test program and other tests is considered. Tests on more sophisticated missions such as ECM, jamming, and combinations of ECM and chaff are addressed. Test data collection techniques are covered.

  12. 49 CFR 570.6 - Brake power unit.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 6 2011-10-01 2011-10-01 false Brake power unit. 570.6 Section 570.6... Pounds or Less § 570.6 Brake power unit. (a) Vacuum hoses shall not be collapsed, abraded, broken... power assist system. This test is not applicable to vehicles equipped with full power brake system...

  13. TGV disc brake squeal

    NASA Astrophysics Data System (ADS)

    Lorang, X.; Foy-Margiocchi, F.; Nguyen, Q. S.; Gautier, P. E.

    2006-06-01

    The discomfort generated by the noise emission of braking systems in trains has aroused recently many studies on the mechanical modelling of brake noise in France. A theoretical and numerical discussion on the phenomenon of brake squeal is given in this paper in relation with some experimental data. This study is based upon a flutter instability analysis giving unstable modes of the brake system under the contact and Coulomb friction.

  14. 49 CFR 571.116 - Standard No. 116; Motor vehicle brake fluids.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... packaged lot and tested simultaneously. Hydraulic system mineral oil means a mineral-oil-based fluid... humidified under controlled conditions; 350 ml. of SAE triethylene glycol monomethyl ether, brake fluid grade... DOT 5 fluids) followed by an acetone or ether rinse. Pass a slow stream of filtered dry air...

  15. 49 CFR 571.116 - Standard No. 116; Motor vehicle brake fluids.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... packaged lot and tested simultaneously. Hydraulic system mineral oil means a mineral-oil-based fluid... humidified under controlled conditions; 350 ml. of SAE triethylene glycol monomethyl ether, brake fluid grade... DOT 5 fluids) followed by an acetone or ether rinse. Pass a slow stream of filtered dry air...

  16. 49 CFR 571.116 - Standard No. 116; Motor vehicle brake fluids.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... packaged lot and tested simultaneously. Hydraulic system mineral oil means a mineral-oil-based fluid... humidified under controlled conditions; 350 ml. of SAE triethylene glycol monomethyl ether, brake fluid grade... DOT 5 fluids) followed by an acetone or ether rinse. Pass a slow stream of filtered dry air...

  17. 49 CFR 393.40 - Required brake systems.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... subpart. (2) Air brake systems. Buses, trucks and truck-tractors equipped with air brake systems and..., trucks and truck tractors manufactured on or after March 1, 1975, and trailers manufactured on or after... and 121 on the date of manufacture. Buses, trucks and truck tractors not subject to FMVSS Nos. 105...

  18. Performance of an aircraft tire under cyclic braking and of a currently operational antiskid braking system

    NASA Technical Reports Server (NTRS)

    Tanner, J. A.

    1972-01-01

    An experimental investigation was conducted to study the performance of an aircraft tire under cyclic braking conditions and to study the performance of a currently operational aircraft antiskid braking system. Dry, damp, and flooded runway surface conditions were used in the investigation. The results indicated that under cyclic braking conditions the braking and cornering-force friction coefficients may be influenced by fluctuations in the vertical load, flexibility in the wheel support, and the spring coupling between the wheel and the tire-pavement interface. The cornering capability was shown to be negligible at wheel slip ratios well below a locked-wheel skid under all test surface conditions. The maximum available brake-force friction coefficient was shown to be dependent upon the runway surface condition, upon velocity, and, for wet runways, upon tire differences. Moderate reductions in vertical load and brake system pressure did not significantly affect the overall wet-runway performance of the tire.

  19. United States Air Force Wipe Solvent Testing

    NASA Technical Reports Server (NTRS)

    Hornung, Steven D.; Beeson, Harold D.

    2000-01-01

    The Wright-Patterson Air Force Base (WPAFB), as part of the Air Force Material Command, requested that NASA Johnson Space Center (JSC) White Sands Test Facility (WSTF) conduct testing and analyses in support of the United States Air Force Wipe Solvent Development Project. The purpose of the wipe solvent project is to develop an alternative to be used by Air Force flight line and maintenance personnel for the wipe cleaning of oxygen equipment. This report provides material compatibility, liquid oxygen (LOX) mechanical impact, autogenous ignition temperature (AIT), and gauge cleaning test data for some of the currently available solvents that may be used to replace CFC-113 and methyl chloroform. It provides data from previous WSTF test programs sponsored by the Naval Sea Systems Command, the Kennedy Space Center, and other NASA programs for the purpose of assisting WP AFB in identifying the best alternative solvents for validation testing.

  20. TESTS OF INDOOR AIR QUALITY SINKS

    EPA Science Inventory

    Experiments were conducted in a room-size test chamber to determine the sink effects of selected materials on indoor air concentrations of p-dichlorobenzene (PDCB). hese effects might alter pollutant behavior from that predicted using similar indoor air quality models, by reducin...

  1. Tests on air propellers in yaw

    NASA Technical Reports Server (NTRS)

    Durand, W F; Lesley, E P

    1923-01-01

    This report contains the results of tests to determine the thrust (pull) and torque characteristics of air propellers in movement relative to the air in a line oblique to the line of the shaft, and specifically when such angle of obliquity is large, as in the case of helicopter flight with the propeller serving for both sustentation and traction.

  2. Experimental Identification of Brake Pad Material Properties—A Step Towards a Better Prediction of Brake Squeal

    NASA Astrophysics Data System (ADS)

    Hornig, Sylwia; Hochlenert, Daniel; von Wagner, Utz

    2010-09-01

    Automotive brake squeal is a disruptive high frequency sound radiation phenomenon generated by friction-induced self-excited vibrations of the brake system. The brake system loses its stability and starts oscillating in a limit cycle with amplitudes limited by nonlinearities, the main origin of the nonlinearities being brake lining material. In order to perform a reliable brake squeal prediction using established mathematical-mechanical models, the knowledge of the lining material properties is of great importance. The present paper deals with the experimental identification of lining material properties, expecially referring to the elastic properties. Since these strongly vary depending on the operating conditions of brake systems, it is necessary to reproduce the operating conditions during brake squeal as close as possible in experimental setups. In this context a special test rig, the test data evaluation and the experimentally determined nonlinear elastic brake lining properties are presented. Assuming these brake lining properties to be the prominent source of the nonlinearity, a nonlinear stability analysis is performed on a realistic disk brake model. The results referring to brake squeal are discussed, whereas basic phenomena known from operating experience of brake systems can be explained on the basis of this analysis.

  3. Breathing air trailer acceptance test procedure

    SciTech Connect

    Kostelnik, A.J.

    1994-09-14

    This Acceptance Test Procedure (ATP) will document compliance with the requirements of WHC-S-0251 Rev. 0 and ECNs 613530 and 606113. The equipment being tested is a Breathing Air Supply Trailer purchased as a Design and Fabrication procurement activity for use in the core sampling program. The ATP was written by the Seller and will be performed by the Seller with representatives of the Westinghouse Hanford Company witnessing the test at the Seller`s location. This test procedure is to verify that the American Bristol Industries, Inc., Model 5014-0001 low pressure Mobile Breathing Air Trailer, meets or exceeds the requirements of the Westinghouse Hanford specification.

  4. Experimental investigation of an accelerometer controlled automatic braking system

    NASA Technical Reports Server (NTRS)

    Dreher, R. C.; Sleeper, R. K.; Nayadley, J. R., Sr.

    1972-01-01

    An investigation was made to determine the feasibility of an automatic braking system for arresting the motion of an airplane by sensing and controlling braked wheel decelerations. The system was tested on a rotating drum dynamometer by using an automotive tire, wheel, and disk-brake assembly under conditions which included two tire loadings, wet and dry surfaces, and a range of ground speeds up to 70 knots. The controlling parameters were the rates at which brake pressure was applied and released and the Command Deceleration Level which governed the wheel deceleration by controlling the brake operation. Limited tests were also made with the automatic braking system installed on a ground vehicle in an effort to provide a more realistic proof of its feasibility. The results of this investigation indicate that a braking system which utilizes wheel decelerations as the control variable to restrict tire slip is feasible and capable of adapting to rapidly changing surface conditions.

  5. Brake Fundamentals. Automotive Articulation Project.

    ERIC Educational Resources Information Center

    Cunningham, Larry; And Others

    Designed for secondary and postsecondary auto mechanics programs, this curriculum guide contains learning exercises in seven areas: (1) brake fundamentals; (2) brake lines, fluid, and hoses; (3) drum brakes; (4) disc brake system and service; (5) master cylinder, power boost, and control valves; (6) parking brakes; and (7) trouble shooting. Each…

  6. Breathing air trailer acceptance test report

    SciTech Connect

    Kostelnik, A.J.

    1996-02-12

    This Acceptance Test Report documents compliance with the requirements of specification WHC-S-0251, Rev.0 and ECNs 613530 and 606113. The equipment was tested according to WHC-SD-WM-ATP-104. The equipment tested is a Breathing Air Supply Trailer purchased as a design and fabrication procurement activity. The ATP was written by the Seller and was performed by the Seller with representatives of the Westinghouse Hanford Company witnessing portions of the test at the Seller`s location.

  7. Reel safety brake

    NASA Technical Reports Server (NTRS)

    Carle, C. E. (Inventor)

    1976-01-01

    A braking apparatus is described for a tape transport device having two stacked coaxial reels and feelers mounted in proximity to the reels for sensing the tape being wound on each reel. A device is mounted in proximity to adjacent central hubs of the reels to a simultaneously, frictionally engage both hubs and brake both reels. A mechanical actuator is coupled to both feelers and to the brake device. The brake means comprises a pair of rubber shoulders that extend in opposite directions relative to a common axis, and turns about the axis in response to either of the feelers.

  8. Landing and Braking of Airplanes

    NASA Technical Reports Server (NTRS)

    Breguet, Louis

    1929-01-01

    In the numerical examples, we have considered an airplane landing in calm air in a fixed direction after crossing the border (with its obstacles) at a height of 30 m. Its stopping point is at a distance D from the obstacle, comprising: a distance D(sub 1) in regular gliding flight; a distance D(sub 2) in levelling off; a distance D(sub 3) in taxying on the ground. The calculations enable us to make out the following table, which gives an idea of the improvements to be expected in the use of various possible methods of braking in the air and on the ground.

  9. An antilock molecular braking system.

    PubMed

    Sun, Wei-Ting; Huang, Shou-Ling; Yao, Hsuan-Hsiao; Chen, I-Chia; Lin, Ying-Chih; Yang, Jye-Shane

    2012-08-17

    A light-driven molecular brake displaying an antilock function is constructed by introducing a nonradiative photoinduced electron transfer (PET) decay channel to compete with the trans (brake-off) → cis (brake-on) photoisomerization. A fast release of the brake can be achieved by deactivating the PET process through addition of protons. The cycle of irradiation-protonation-irradiation-deprotonation conducts the brake function and mimics the antilock braking system (ABS) of vehicles. PMID:22853709

  10. 49 CFR 393.55 - Antilock brake systems.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... FMVSS No. 105 (49 CFR 571.105, S5.3). (c) Air brake systems. (1) Each truck tractor manufactured on or... Motor Vehicle Safety Standard (FMVSS) No. 105 (49 CFR 571.105, S5.5). (b) ABS malfunction indicators for... with an antilock brake system that meets the requirements of FMVSS No. 121 (49 CFR 571.121,...

  11. 49 CFR 393.55 - Antilock brake systems.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... indicator system that meets the requirements of FMVSS No. 105 (49 CFR 571.105, S5.3). (c) Air brake systems... or transmission of response or control signals to the vehicle's antilock brake system (49 CFR 571.121... meets the requirements of Federal Motor Vehicle Safety Standard (FMVSS) No. 105 (49 CFR 571.105,...

  12. 49 CFR 393.55 - Antilock brake systems.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... indicator system that meets the requirements of FMVSS No. 105 (49 CFR 571.105, S5.3). (c) Air brake systems... or transmission of response or control signals to the vehicle's antilock brake system (49 CFR 571.121... meets the requirements of Federal Motor Vehicle Safety Standard (FMVSS) No. 105 (49 CFR 571.105,...

  13. 49 CFR 393.55 - Antilock brake systems.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... indicator system that meets the requirements of FMVSS No. 105 (49 CFR 571.105, S5.3). (c) Air brake systems... or transmission of response or control signals to the vehicle's antilock brake system (49 CFR 571.121... meets the requirements of Federal Motor Vehicle Safety Standard (FMVSS) No. 105 (49 CFR 571.105,...

  14. 49 CFR 393.55 - Antilock brake systems.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... indicator system that meets the requirements of FMVSS No. 105 (49 CFR 571.105, S5.3). (c) Air brake systems... or transmission of response or control signals to the vehicle's antilock brake system (49 CFR 571.121... meets the requirements of Federal Motor Vehicle Safety Standard (FMVSS) No. 105 (49 CFR 571.105,...

  15. A New Dynamometer Brake

    NASA Technical Reports Server (NTRS)

    Segre, Marco

    1921-01-01

    The mechanism here described belongs to the class of dynamometer brake in which the motive power is transformed into heat in the brake itself. This mechanism was invented by the writer for the purpose of measuring forces in which the two factors, torque and speed, vary within broad limits, the mechanism itself being of simple construction and of still simpler operation.

  16. ASTM Validates Air Pollution Test Methods

    ERIC Educational Resources Information Center

    Chemical and Engineering News, 1973

    1973-01-01

    The American Society for Testing and Materials (ASTM) has validated six basic methods for measuring pollutants in ambient air as the first part of its Project Threshold. Aim of the project is to establish nationwide consistency in measuring pollutants; determining precision, accuracy and reproducibility of 35 standard measuring methods. (BL)

  17. 14 CFR 25.735 - Brakes and braking systems.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Brakes and braking systems. 25.735 Section 25.735 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Design and Construction Landing Gear § 25.735 Brakes and braking systems. (a) Approval....

  18. Space shuttle wheels and brakes

    NASA Technical Reports Server (NTRS)

    Carsley, R. B.

    1985-01-01

    The Space Shuttle Orbiter wheels were subjected to a combination of tests which are different than any previously conducted in the aerospace industry. The major testing difference is the computer generated dynamic landing profiles used during the certification process which subjected the wheels and tires to simulated landing loading conditions. The orbiter brakes use a unique combination of carbon composite linings and beryllium heat sink to minimize weight. The development of a new lining retention method was necessary in order to withstand the high temperature generated during the braking roll. As with many programs, the volume into which this hardware had to fit was established early in the program, with no provisions made for growth to offset the continuously increasing predicted orbiter landing weight.

  19. Improved Electromagnetic Brake

    NASA Technical Reports Server (NTRS)

    Martin, Toby B.

    2004-01-01

    A proposed design for an electromagnetic brake would increase the reliability while reducing the number of parts and the weight, relative to a prior commercially available electromagnetic brake. The reductions of weight and the number of parts could also lead to a reduction of cost. A description of the commercial brake is prerequisite to a description of the proposed electromagnetic brake. The commercial brake (see upper part of figure) includes (1) a permanent magnet and an electromagnet coil on a stator and (2) a rotor that includes a steel contact plate mounted, with tension spring loading, on an aluminum hub. The stator is mounted securely on a stationary object, which would ordinarily be the housing of a gear drive or a motor. The rotor is mounted on the shaft of the gear drive or motor. The commercial brake nominally operates in a fail-safe (in the sense of normally braking) mode: In the absence of current in the electromagnet coil, the permanent magnet pulls the contact plate, against the spring tension, into contact with the stator. To release the brake, one excites the electromagnet with a current of the magnitude and polarity chosen to cancel the magnetic flux of the permanent magnet, thereby enabling the spring tension to pull the contact plate out of contact with the stator. The fail-safe operation of the commercial brake depends on careful mounting of the rotor in relation to the stator. The rotor/stator gap must be set with a tolerance between 10 and 15 mils (between about 0.25 and about 0.38 mm). If the gap or the contact pad is thicker than the maximum allowable value, then the permanent magnetic field will not be strong enough to pull the steel plate across the gap. (For this reason, any contact pad between the contact plate and the stator must also be correspondingly thin.) If the gap exceeds the maximum allowable value because of shaft end play, it becomes impossible to set the brake by turning off the electromagnet current. Although it may

  20. Consideration of Materials for Aircraft Brakes

    NASA Technical Reports Server (NTRS)

    Peterson, M. B.; Ho, T.

    1972-01-01

    An exploratory investigation was conducted concerning materials and their properties for use in aircraft brakes. Primary consideration was given to the heat dissipation and the frictional behavior of materials. Used brake pads and rotors were analyzed as part of the investigation. A simple analysis was conducted in order to determine the most significant factors which affect surface temperatures. It was found that where size and weight restrictions are necessary, the specific heat of the material, and maintaining uniform contact area are the most important factors. A criterion was suggested for optimum sizing of the brake disks. Bench friction tests were run with brake materials. It was found that there is considerable friction variation due to the formation and removal of surface oxide films. Other causes of friction variations are surface softening and melting. The friction behavior at high temperature was found to be more characteristic of the steel surface rather than the copper brake material. It is concluded that improved brake materials are feasible.

  1. Control of asbestos exposure during brake drum service

    SciTech Connect

    Sheehy, J.W.; Cooper, T.C.; O'Brien, D.M.; McGlothlin, J.D.; Froehlich, P.A.

    1989-08-01

    Earlier studies of airborne asbestos exposure to mechanics during brake maintenance operations showed overexposure to asbestos fibers during brake servicing, especially brake assembly cleaning. Because an estimated 150,000 brake mechanics and garage workers in the U.S. are potentially exposed to asbestos, a known carcinogen, and the lack of information available on the effectiveness of available controls, an evaluation of these methods was initiated. Detailed field surveys were conducted at five facilities employing five methods for controlling exposure to asbestos during brake repair. These included the use of two commercial enclosure devices with ventilation provided by HEPA filter-equipped vacuum, a HEPA filter-equipped vacuum alone, a brush with recirculating cleaning solution, and cleaning solvents in aerosol cans. These controls were evaluated while servicing brakes to automobiles, pickup trucks, vans, and vehicles with a 4-wheel rear axle. Detailed evaluations of these control measures involved a program consisting of traditional air sampling methods, incorporating phase contrast microscopy (PCM) and transmission electron microscopy (TEM), and a real-time analysis of brake dust exposure. Personal and area air samples were collected during brake repair to each vehicle.

  2. Evaluation of materials and design modifications for aircraft brakes

    NASA Technical Reports Server (NTRS)

    Ho, T. L.; Kennedy, F. E.; Peterson, M. B.

    1975-01-01

    A test program is described which was carried out to evaluate several proposed design modifications and several high-temperature friction materials for use in aircraft disk brakes. The evaluation program was carried out on a specially built test apparatus utilizing a disk brake and wheel half from a small het aircraft. The apparatus enabled control of brake pressure, velocity, and braking time. Tests were run under both constant and variable velocity conditions and covered a kinetic energy range similar to that encountered in aircraft brake service. The results of the design evaluation program showed that some improvement in brake performance can be realized by making design changes in the components of the brake containing friction material. The materials evaluation showed that two friction materials show potential for use in aircraft disk brakes. One of the materials is a nickel-based sintered composite, while the other is a molybdenum-based material. Both materials show much lower wear rates than conventional copper-based materials and are better able to withstand the high temperatures encountered during braking. Additional materials improvement is necessary since both materials show a significant negative slope of the friction-velocity curve at low velocities.

  3. Load proportional safety brake

    NASA Technical Reports Server (NTRS)

    Cacciola, M. J.

    1979-01-01

    This brake is a self-energizing mechanical friction brake and is intended for use in a rotary drive system. It incorporates a torque sensor which cuts power to the power unit on any overload condition. The brake is capable of driving against an opposing load or driving, paying-out, an aiding load in either direction of rotation. The brake also acts as a no-back device when torque is applied to the output shaft. The advantages of using this type of device are: (1) low frictional drag when driving; (2) smooth paying-out of an aiding load with no runaway danger; (3) energy absorption proportional to load; (4) no-back activates within a few degrees of output shaft rotation and resets automatically; and (5) built-in overload protection.

  4. Air-breathing Rocket Engine Test

    NASA Technical Reports Server (NTRS)

    1999-01-01

    This Quick Time movie depicts the Rocketdyne static test of an air-breathing rocket. Air-breathing engines, known as rocket based, combined-cycle engines, get their initial take-off power from specially designed rockets, called air-augmented rockets, that boost performance about 15 percent over conventional rockets. When the vehicle's velocity reaches twice the speed of sound, the rockets are turned off and the engine relies totally on oxygen in the atmosphere to burn hydrogen fuel, as opposed to a rocket that must carry its own oxygen, thus reducing weight and flight costs. Once the vehicle has accelerated to about 10 times the speed of sound, the engine converts to a conventional rocket-powered system to propel the craft into orbit or sustain it to suborbital flight speed. NASA's advanced Transportation Program at the Marshall Space Flight Center, along with several industry partners and collegiate forces, is developing this technology to make space transportation affordable for everyone from business travelers to tourists. The goal is to reduce launch costs from today's price tag of $10,000 per pound to only hundreds of dollars per pound. NASA's series of hypersonic flight demonstrators currently include three air-breathing vehicles: the X-43A, X-43B and X-43C.

  5. A unique concept for automatically controlling the braking action of wheeled vehicles during minimum distance stops

    NASA Technical Reports Server (NTRS)

    Barthlome, D. E.

    1975-01-01

    Test results of a unique automatic brake control system are outlined and a comparison is made of its mode of operation to that of an existing skid control system. The purpose of the test system is to provide automatic control of braking action such that hydraulic brake pressure is maintained at a near constant, optimum value during minimum distance stops.

  6. Optical Air Flow Measurements for Flight Tests and Flight Testing Optical Air Flow Meters

    NASA Technical Reports Server (NTRS)

    Jentink, Henk W.; Bogue, Rodney K.

    2005-01-01

    Optical air flow measurements can support the testing of aircraft and can be instrumental to in-flight investigations of the atmosphere or atmospheric phenomena. Furthermore, optical air flow meters potentially contribute as avionics systems to flight safety and as air data systems. The qualification of these instruments for the flight environment is where we encounter the systems in flight testing. An overview is presented of different optical air flow measurement techniques applied in flight and what can be achieved with the techniques for flight test purposes is reviewed. All in-flight optical airflow velocity measurements use light scattering. Light is scattered on both air molecules and aerosols entrained in the air. Basic principles of making optical measurements in flight, some basic optical concepts, electronic concepts, optoelectronic interfaces, and some atmospheric processes associated with natural aerosols are reviewed. Safety aspects in applying the technique are shortly addressed. The different applications of the technique are listed and some typical examples are presented. Recently NASA acquired new data on mountain rotors, mountain induced turbulence, with the ACLAIM system. Rotor position was identified using the lidar system and the potentially hazardous air flow profile was monitored by the ACLAIM system.

  7. Wear Modalities and Mechanisms of the Mining Non-asbestos Composite Brake Material

    NASA Astrophysics Data System (ADS)

    Bao, Jiusheng; Yin, Yan; Zhu, Zhencai; Tong, Minming; Lu, Yuhao; Peng, Yuxing

    2013-08-01

    The mining brake material is generally made of composite materials and its wear has important influences on the braking performance of disc brakes. In order to improve the braking reliability of mine hoisters, this paper did some tribological investigations on the mining brake material to reveal its wear modalities and mechanisms. The mining non-asbestos brake shoe and 16Mn steel were selected as braking pairs and tested on a pad-on-disc friction tester. And a SEM was used to observe the worn surface of the brake shoe. It is shown that the non-asbestos brake material has mainly five wear modalities: adhesive wear, abrasive wear, cutting wear, fatigue wear and high heat wear. At the front period of a single braking the wear modality is mainly composed of some light mechanical wear such as abrasive, cutting and point adhesive. With the temperature rising at the back period it transforms to some heavy mechanical wear such as piece adhesive and fatigue. While in several repeated brakings once the surface temperature rises beyond the thermal-decomposition point of the bonding material, the strong destructive high heat wear takes leading roles on the surface. And a phenomenon called friction catastrophe (FC) occurs easily, which as a result causes a braking failure. It is considered that the friction heat has important influences on the wear modalities of the brake material. And the reduction of friction heat must be an effective technical method for decreasing wear and avoiding braking failures.

  8. Advanced air revitalization system modeling and testing

    NASA Technical Reports Server (NTRS)

    Dall-Baumann, Liese; Jeng, Frank; Christian, Steve; Edeer, Marybeth; Lin, Chin

    1990-01-01

    To support manned lunar and Martian exploration, an extensive evaluation of air revitalization subsystems (ARS) is being conducted. The major operations under study include carbon dioxide removal and reduction; oxygen and nitrogen production, storage, and distribution; humidity and temperature control; and trace contaminant control. A comprehensive analysis program based on a generalized block flow model was developed to facilitate the evaluation of various processes and their interaction. ASPEN PLUS was used in modelling carbon dioxide removal and reduction. Several life support test stands were developed to test new and existing technologies for their potential applicability in space. The goal was to identify processes which use compact, lightweight equipment and maximize the recovery of oxygen and water. The carbon dioxide removal test stands include solid amine/vacuum desorption (SAVD), regenerative silver oxide chemisorption, and electrochemical carbon dioxide concentration (EDC). Membrane-based carbon dioxide removal and humidity control, catalytic reduction of carbon dioxide, and catalytic oxidation of trace contaminants were also investigated.

  9. Asbestos exposures during reprocessing of automobile brakes and clutches.

    PubMed

    Sakai, Kiyoshi; Hisanaga, Naomi; Shibata, Eiji; Ono, Yuichiro; Takeuchi, Yasuhiro

    2006-01-01

    Asbestos exposures of workers in three small factories reprocessing automobile brakes and clutches in Japan were investigated. Airborne asbestos was collected on a membrane filter using an air sampler. From 1982 to 1989, asbestos counting was performed on 295 samples (198 personal and 97 stationary), using phase contrast microscopy. Only chrysotile asbestos was detected. Workers who reprocessed automobile brakes and clutches were exposed to asbestos concentrations of 0.025-76.4 fibers/cm3. Geometric mean asbestos concentrations during attaching linings to brake shoes and attaching facings to clutch disks were 0.859 fibers/cm3 and 0.780 fibers/cm3, respectively. Concentrations during stripping worn brake linings and clutch facings were 0.484 fibers/cm3 and 0.382 fibers/cm3, respectively. Machine grinding and leveling of new brake-lining surfaces represent potential sources of heavy asbestos exposures, unless enclosures and local ventilation are efficient. PMID:16722188

  10. 14 CFR 25.735 - Brakes and braking systems.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... declared fully worn limit(s) of the brake heat sink, the wheel, brake and tire assembly is capable of... heat sink is worn to the permissible limit. The means must be reliable and readily visible....

  11. 14 CFR 25.735 - Brakes and braking systems.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... declared fully worn limit(s) of the brake heat sink, the wheel, brake and tire assembly is capable of... heat sink is worn to the permissible limit. The means must be reliable and readily visible....

  12. 14 CFR 25.735 - Brakes and braking systems.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... declared fully worn limit(s) of the brake heat sink, the wheel, brake and tire assembly is capable of... heat sink is worn to the permissible limit. The means must be reliable and readily visible....

  13. 14 CFR 25.735 - Brakes and braking systems.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... declared fully worn limit(s) of the brake heat sink, the wheel, brake and tire assembly is capable of... heat sink is worn to the permissible limit. The means must be reliable and readily visible....

  14. Air-Breathing Rocket Engine Test

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This photograph depicts an air-breathing rocket engine that completed an hour or 3,600 seconds of testing at the General Applied Sciences Laboratory in Ronkonkoma, New York. Referred to as ARGO by its design team, the engine is named after the mythological Greek ship that bore Jason and the Argonauts on their epic voyage of discovery. Air-breathing engines, known as rocket based, combined-cycle engines, get their initial take-off power from specially designed rockets, called air-augmented rockets, that boost performance about 15 percent over conventional rockets. When the vehicle's velocity reaches twice the speed of sound, the rockets are turned off and the engine relies totally on oxygen in the atmosphere to burn hydrogen fuel, as opposed to a rocket that must carry its own oxygen, thus reducing weight and flight costs. Once the vehicle has accelerated to about 10 times the speed of sound, the engine converts to a conventional rocket-powered system to propel the craft into orbit or sustain it to suborbital flight speed. NASA's Advanced SpaceTransportation Program at Marshall Space Flight Center, along with several industry partners and collegiate forces, is developing this technology to make space transportation affordable for everyone from business travelers to tourists. The goal is to reduce launch costs from today's price tag of $10,000 per pound to only hundreds of dollars per pound. NASA's series of hypersonic flight demonstrators currently include three air-breathing vehicles: the X-43A, X-43B and X-43C.

  15. 49 CFR 238.309 - Periodic brake equipment maintenance.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Periodic brake equipment maintenance. 238.309... Maintenance Requirements for Tier I Passenger Equipment § 238.309 Periodic brake equipment maintenance. (a... passenger equipment shall be periodically cleaned, repaired, and tested. This maintenance procedure...

  16. 30 CFR 57.14101 - Brakes.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Machinery and Equipment Safety... shall be maintained in functional condition. (b) Testing. (1) Service brake tests shall be conducted...

  17. 30 CFR 56.14101 - Brakes.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Machinery and Equipment Safety... shall be maintained in functional condition. (b) Testing. (1) Service brake tests shall be...

  18. 30 CFR 57.14101 - Brakes.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Machinery and Equipment Safety... shall be maintained in functional condition. (b) Testing. (1) Service brake tests shall be conducted...

  19. 30 CFR 56.14101 - Brakes.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Machinery and Equipment Safety... shall be maintained in functional condition. (b) Testing. (1) Service brake tests shall be...

  20. 30 CFR 57.14101 - Brakes.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Machinery and Equipment Safety... shall be maintained in functional condition. (b) Testing. (1) Service brake tests shall be conducted...

  1. 30 CFR 56.14101 - Brakes.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Machinery and Equipment Safety... shall be maintained in functional condition. (b) Testing. (1) Service brake tests shall be...

  2. Design of haptic master featuring small-sized MR brakes

    NASA Astrophysics Data System (ADS)

    Gang, Han Gyeol; Choi, Seung-Bok; Sohn, Jung Woo

    2016-04-01

    In this work, a new type of haptic master featuring small-sized MR brake is proposed and its performances are evaluated. The proposed haptic master consists of base frame, stick grip and small-sized four MR brakes for 3-DOF rotational motion and 1-DOF gripper motion. To obtain large braking torque under limited small size of MR brake, dual tapered shape inner magnetic core is proposed and its performance is evaluated via both numerical estimation and experimental test. After design and implementation of control algorithm, it has been demonstrated through experiment that the proposed actuator has good performances on tracking control of desired torques. Then, a new haptic master device is designed and constructed by adopting the proposed MR brakes and light weight frame structures. It is verified that the proposed haptic master device is effective for the real application in the field.

  3. Use of elastomers in regenerative braking systems

    NASA Astrophysics Data System (ADS)

    The storage of potential energy as strain energy in elastomers was investigated. The evolution of the preferred stressing scheme is described, and test results on full-size elastomeric energy storage units sized for an automotive regenerative braking system application are presented. The need for elastomeric material improvements is also discussed.

  4. Wind-Tunnel Tests on Various Types of Dive Brakes Mounted in Proximity of the Leading Edge of the Wing

    NASA Technical Reports Server (NTRS)

    Lattanzi, Bernardino; Bellante, Erno

    1949-01-01

    The present report is concerned with a series of tests on a model airplane fitted with four types of dive flaps of various shapes, positions, and incidence located near the leading edge of the wing (from 5 to 20 percent of the wing chord). Tests were also made on a stub airfoil fitted with a ventral dive (located at 8 percent of the wing chord). The hinge moments of the dive flaps were measured.

  5. Comparative analysis into the tractor-trailer braking dynamics: tractor with single axle brakes, tractor with all wheel brakes

    NASA Astrophysics Data System (ADS)

    Nastasoiu, Mircea; Ispas, Nicolae

    2014-06-01

    The paper elaborates a mathematical model in order to conduct a study into the dynamics of tractor-trailer systems during braking. The braking dynamics is analyzed by considering two versions for the braking system: 1) braking applied on the rear axle and 2) braking applied on all four wheels. In both versions the trailer is braked on all wheels. The mathematical model enables us to determine and graphically illustrate the evolution of the following parameters: braking deceleration, braking speed and the distance traveled by the tractor during braking. The mathematical model elaborated is applied on a tractor-trailer system completing transportation works.

  6. Acceptance Test Report for 241-U compressed air system

    SciTech Connect

    Freeman, R.D.

    1994-10-20

    This Acceptance Test Report (ATR) documents the results of acceptance testing of a newly upgraded compressed air system at 241-U Farm. The system was installed and the test successfully performed under work package 2W-92-01027.

  7. Wear formulation for aircraft brake material sliding against steel

    NASA Technical Reports Server (NTRS)

    Ho, T. L.; Peterson, M. B.

    1977-01-01

    Predictions of wear on contemporary copper-based brake material sliding against 17-22 AS grade steel, wear testing equipment, formulation of wear, and test results are discussed. An initial investigation of worn surfaces of the brake material and a mating steel rotor was carried out. A wear model proposed suggests initiation of cracks at a hard particle inclusion site in the surface layer of the brake material; crack propagation allows particles to be removed by intersection of cracks. Mutual relations between sliding variables, load, time, hardness, and surface temperature are studied. Empirical formulas are exhibited.

  8. 49 CFR 393.52 - Brake performance.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 5 2012-10-01 2012-10-01 false Brake performance. 393.52 Section 393.52... NECESSARY FOR SAFE OPERATION Brakes § 393.52 Brake performance. (a) Upon application of its service brakes... of the service brake pedal or control begins, that is not greater than the distance specified in...

  9. 49 CFR 393.52 - Brake performance.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 5 2014-10-01 2014-10-01 false Brake performance. 393.52 Section 393.52... NECESSARY FOR SAFE OPERATION Brakes § 393.52 Brake performance. (a) Upon application of its service brakes... of the service brake pedal or control begins, that is not greater than the distance specified in...

  10. Sprag solenoid brake. [development and operations of electrically controlled brake

    NASA Technical Reports Server (NTRS)

    Dane, D. H. (Inventor)

    1974-01-01

    The development and characteristics of an electrically operated brake are discussed. The action of the brake depends on energizing a solenoid which causes internally spaced sprockets to contact the inner surface of the housing. A spring forces the control member to move to the braking position when the electrical function is interrupted. A diagram of the device is provided and detailed operating principles are explained.

  11. 49 CFR 570.56 - Vacuum brake assist unit and vacuum brake system.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 6 2012-10-01 2012-10-01 false Vacuum brake assist unit and vacuum brake system... Vehicles With GVWR of More Than 10,000 Pounds § 570.56 Vacuum brake assist unit and vacuum brake system. The following requirements apply to vehicles with vacuum brake assist units and vacuum brake...

  12. 49 CFR 570.56 - Vacuum brake assist unit and vacuum brake system.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 6 2014-10-01 2014-10-01 false Vacuum brake assist unit and vacuum brake system... Vehicles With GVWR of More Than 10,000 Pounds § 570.56 Vacuum brake assist unit and vacuum brake system. The following requirements apply to vehicles with vacuum brake assist units and vacuum brake...

  13. 49 CFR 570.56 - Vacuum brake assist unit and vacuum brake system.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 6 2011-10-01 2011-10-01 false Vacuum brake assist unit and vacuum brake system... Vehicles With GVWR of More Than 10,000 Pounds § 570.56 Vacuum brake assist unit and vacuum brake system. The following requirements apply to vehicles with vacuum brake assist units and vacuum brake...

  14. 49 CFR 570.56 - Vacuum brake assist unit and vacuum brake system.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 6 2013-10-01 2013-10-01 false Vacuum brake assist unit and vacuum brake system... Vehicles With GVWR of More Than 10,000 Pounds § 570.56 Vacuum brake assist unit and vacuum brake system. The following requirements apply to vehicles with vacuum brake assist units and vacuum brake...

  15. Tether Deployer And Brake

    NASA Technical Reports Server (NTRS)

    Carroll, Joseph A.; Alexander, Charles M.

    1993-01-01

    Design concept promises speed, control, and reliability. Scheme for deploying tether provides for fast, free, and snagless payout and fast, dependable braking. Developed for small, expendable tethers in outer space, scheme also useful in laying transoceanic cables, deploying guidance wires to torpedoes and missiles, paying out rescue lines from ship to ship via rockets, deploying antenna wires, releasing communication and power cables to sonobuoys and expendable bathythermographs, and in reeling out lines from fishing rods.

  16. An Investigation of the Aerodynamic Characteristics of an 0.08-Scale Model of the Chance Vought XF7U-1 Airplane in the Langley High-Speed 7- by 10-Foot Tunnel. Part V - Wing-Alone Tests and Effect of Modifications to the Vertical Fins, Speed Brakes, and Fuselage TED No. NACA DE308. Part V; Wing-Alone Tests and Effect of Modifications to the Vertical Fins, Speed Brakes, and Fuselage, TED No. NACA DE308

    NASA Technical Reports Server (NTRS)

    Kuhri, Richard E.; Myers, Boyd C., II

    1947-01-01

    Tests have been conducted in the Langley high-speed 7- by 10-foot tunnel over a Mach number range from 0.40 to 0.91 to determine the stability and control characteristics of an 0.08-scale model of the Chance Vought XF7U-1 airplane. The wing-alone tests and the effect of the various vertical-fin modifications, speed-brake modifications, and fuselage modifications on the aerodynamic characteristics in pitch and yaw are presented in the present paper with a limited analysis of the results. Also included are tuft studies of the flow for some of the modifications tested.

  17. Air Pollution Tests Using the "DEMA"

    ERIC Educational Resources Information Center

    Wilt, L. M.

    1970-01-01

    Describes the making and calibrating of a DEMA (DEvice for Measuring Air) from readily available, inexpensive materials. Procedures for measuring atmospheric particulates, acids, and carbon monoxide are described. (PR)

  18. Interpretation of prematurely terminated air-pressurized slug tests

    USGS Publications Warehouse

    Shapiro, Allen M.; Greene, Earl A.

    1995-01-01

    An air-pressurized slug test consists of applying a constant pressure to the column of air in a well, monitoring the declining water level, and then releasing the air pressure and monitoring the recovering water level. Such tests offer a means of estimating formation transmissivity and storativity without extensive downhole equipment and the associated safety risks. This paper analyzes data from prematurely terminated tests. A solution to the boundary-value problem for the declining and recovering water level during an air-pressurized slug test is developed for an arbitrary time-dependent air pressure applied to the well. Type curves are generated to estimate formation transmissivity and storativity from the recovering water level associated with prematurely, terminated tests. The application of the type curves is illustrated in a series of actual tests.

  19. Combined hydraulic and regenerative braking system

    SciTech Connect

    Mericle, G.E.; Venkataperumal, R.R.

    1981-06-02

    A combined hydraulic and regenerative braking system and method is disclosed for an electric vehicle. The braking system being responsive to the applied hydraulic pressure in a brake line to control the braking of the vehicle to be completely hydraulic up to a first level of brake line pressure, to be partially hydraulic at a constant braking force and partially regenerative at a linearly increasing braking force from the first level of applied brake line pressure to a higher second level of brake line pressure, to be partially hydraulic at a linearly increasing braking force and partially regenerative at a linearly decreasing braking force from the second level of applied line pressure to a third and higher level of applied line pressure, and to be completely hydraulic at a linearly increasing braking force from the third level to all higher applied levels of line pressure.

  20. Combined hydraulic and regenerative braking system

    DOEpatents

    Venkataperumal, Rama R.; Mericle, Gerald E.

    1981-06-02

    A combined hydraulic and regenerative braking system and method for an electric vehicle, with the braking system being responsive to the applied hydraulic pressure in a brake line to control the braking of the vehicle to be completely hydraulic up to a first level of brake line pressure, to be partially hydraulic at a constant braking force and partially regenerative at a linearly increasing braking force from the first level of applied brake line pressure to a higher second level of brake line pressure, to be partially hydraulic at a linearly increasing braking force and partially regenerative at a linearly decreasing braking force from the second level of applied line pressure to a third and higher level of applied line pressure, and to be completely hydraulic at a linearly increasing braking force from the third level to all higher applied levels of line pressure.

  1. Combined hydraulic and regenerative braking system

    DOEpatents

    Venkataperumal, R.R.; Mericle, G.E.

    1979-08-09

    A combined hydraulic and regenerative braking system and method for an electric vehicle is disclosed. The braking system is responsive to the applied hydraulic pressure in a brake line to control the braking of the vehicle to be completely hydraulic up to a first level of brake line pressure, to be partially hydraulic at a constant braking force and partially regenerative at a linearly increasing braking force from the first level of applied brake line pressure to a higher second level of brake line pressure, to be partially hydraulic at a linearly increasing braking force and partially regenerative at a linearly decreasing braking force from the second level of applied line pressure to a third and higher level of applied line pressure, and to be completely hydraulic at a linearly increasing braking force from the third level to all higher applied levels of line pressure.

  2. Theoretical and experimental studies on a magnetorheological brake operating under compression plus shear mode

    NASA Astrophysics Data System (ADS)

    Sarkar, C.; Hirani, H.

    2013-11-01

    The torque characteristics of magnetorheological brakes, consisting of rotating disks immersed in a MR fluid and enclosed in an electromagnetic casing, are controlled by regulating the yield stress of the MR fluid. An increase in yield stress increases the braking torque, which means that the higher the yield strength of the MR fluid, the better the performance of the MR brake will be. In the present research an application of compressive force on MR fluid has been proposed to increase the torque capacity of MR brakes. The mathematical expressions to estimate the torque values for MR brake, operating under compression plus shear mode accounting Herschel-Bulkley shear thinning model, have been detailed. The required compressive force on MR fluid of the proposed brake has been applied using an electromagnetic actuator. The development of a single-plate MR disk brake and an experimental test rig are described. Experiments have been performed to illustrate braking torque under different control currents (0.0-2.0 A). The torque results have been plotted and compared with theoretical study. Experimental results as well as theoretical calculations indicate that the braking torque of the proposed MR brake is higher than that of the MR brake operating only under shear.

  3. 49 CFR 393.47 - Brake actuators, slack adjusters, linings/pads and drums/rotors.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... drums/rotors. 393.47 Section 393.47 Transportation Other Regulations Relating to Transportation..., slack adjusters, linings/pads and drums/rotors. (a) General requirements. Brake components must be... shoe with two pads; or worn to the wear indicator if the lining is so marked, for air drum brakes....

  4. 49 CFR 393.47 - Brake actuators, slack adjusters, linings/pads and drums/rotors.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... drums/rotors. 393.47 Section 393.47 Transportation Other Regulations Relating to Transportation..., slack adjusters, linings/pads and drums/rotors. (a) General requirements. Brake components must be... shoe with two pads; or worn to the wear indicator if the lining is so marked, for air drum brakes....

  5. 49 CFR 393.47 - Brake actuators, slack adjusters, linings/pads and drums/rotors.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... drums/rotors. 393.47 Section 393.47 Transportation Other Regulations Relating to Transportation..., slack adjusters, linings/pads and drums/rotors. (a) General requirements. Brake components must be... shoe with two pads; or worn to the wear indicator if the lining is so marked, for air drum brakes....

  6. 49 CFR 393.47 - Brake actuators, slack adjusters, linings/pads and drums/rotors.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... drums/rotors. 393.47 Section 393.47 Transportation Other Regulations Relating to Transportation..., slack adjusters, linings/pads and drums/rotors. (a) General requirements. Brake components must be... shoe with two pads; or worn to the wear indicator if the lining is so marked, for air drum brakes....

  7. 49 CFR 393.47 - Brake actuators, slack adjusters, linings/pads and drums/rotors.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... drums/rotors. 393.47 Section 393.47 Transportation Other Regulations Relating to Transportation..., slack adjusters, linings/pads and drums/rotors. (a) General requirements. Brake components must be... shoe with two pads; or worn to the wear indicator if the lining is so marked, for air drum brakes....

  8. PERFORMANCE TESTING OF AIR CLEANING PRODUCTS

    EPA Science Inventory

    The paper discuses the application of the Environmental Technology Verification (ETV) Program for products that clean ventilation air to the problem of protecting buildings from chemical and biological attack. This program is funded by the U.S. Environmental Protection Agency und...

  9. MSFC hot air collectors. Phase 1: Test report

    NASA Technical Reports Server (NTRS)

    Losey, R.

    1977-01-01

    A development test program of 3 hot air flat plate solar collectors is described in detail. The pressure drop versus flow rate performance characteristics for these collectors, mounted in series, was determined under 14 different test conditions each of which was characterized by a unique combination of inlet air temperature and air flow rate. Characteristics of inlet, exit and transfer ducts of these collectors were also determined during this testing. The test results indicate that significant pressure drop occurs at air flow rates greater than 150 standard cubic feet per minute and this drop is not heavily dependent upon inlet air temperature; and inlet, exit and transfer duct characteristics differ sufficiently to suggest that system performance may be enhanced through careful design of each type of duct individually.

  10. Chaos in brake squeal noise

    NASA Astrophysics Data System (ADS)

    Oberst, S.; Lai, J. C. S.

    2011-02-01

    Brake squeal has become an increasing concern to the automotive industry because of warranty costs and the requirement for continued interior vehicle noise reduction. Most research has been directed to either analytical and experimental studies of brake squeal mechanisms or the prediction of brake squeal propensity using finite element methods. By comparison, there is a lack of systematic analysis of brake squeal data obtained from a noise dynamometer. It is well known that brake squeal is a nonlinear transient phenomenon and a number of studies using analytical and experimental models of brake systems (e.g., pin-on-disc) indicate that it could be treated as a chaotic phenomenon. Data obtained from a full brake system on a noise dynamometer were examined with nonlinear analysis techniques. The application of recurrence plots reveals chaotic structures even in noisy data from the squealing events. By separating the time series into different regimes, lower dimensional attractors are isolated and quantified by dynamic invariants such as correlation dimension estimates or Lyapunov exponents. Further analysis of the recurrence plot of squealing events by means of recurrence quantification analysis measures reveals different regimes of laminar and random behaviour, periodicity and chaos-forming recurrent transitions. These results help to classify brake squeal mechanisms and to enhance understanding of friction-related noise phenomena.

  11. Radiant heat test of Perforated Metal Air Transportable Package (PMATP).

    SciTech Connect

    Gronewald, Patrick James; Oneto, Robert; Mould, John; Pierce, Jim Dwight

    2003-08-01

    A conceptual design for a plutonium air transport package capable of surviving a 'worst case' airplane crash has been developed by Sandia National Laboratories (SNL) for the Japan Nuclear Cycle Development Institute (JNC). A full-scale prototype, designated as the Perforated Metal Air Transport Package (PMATP) was thermally tested in the SNL Radiant Heat Test Facility. This testing, conducted on an undamaged package, simulated a regulation one-hour aviation fuel pool fire test. Finite element thermal predictions compared well with the test results. The package performed as designed, with peak containment package temperatures less than 80 C after exposure to a one-hour test in a 1000 C environment.

  12. Computer Simulation for Air-coupled Ultrasonic Testing

    NASA Astrophysics Data System (ADS)

    Yamawaki, H.

    2014-06-01

    Air-coupled ultrasound is used as non-contact ultrasonic testing method. For wider application of air-coupled ultrasonic technique, it is required to know situation of ultrasonic propagation between air and solid. Transmittance of the ultrasonic waves from air to solids is extremely small with 10-5 however it was revealed that, by using computer simulation methods based on the two-stage elastic wave equation in which two independent variables of stress and particle velocity are used, visualization calculation of ultrasonic propagation between air and solid was possible. In this report, the calculation of air-coupled ultrasound using the new Improved-FDM for computer simulation of ultrasonic propagation in solids is shown. Waveforms obtained by 1-dimensional calculation are discussed for principle and performance of the calculation. Visualization of ultrasonic incidence to cylindrical steel pipe is demonstrated as an example to show availability for ultrasonic testing.

  13. Brake power servo booster

    SciTech Connect

    Kobayashi, M.; Shimamura, M.

    1988-04-19

    A brake power servo booster is described comprising: a power piston; a power piston return spring; at least two shells enclosing at least a portion of the power piston and defining a constant pressure chamber and a variable pressure chamber; a master cylinder for controlling the application of hydraulic pressure to a brake mechanism; an input shaft; a hollow cylindrical member integrally connected to the input shaft, a stopper member for limiting movement of the hollow cylindrical member in the second direction, a hollow output shaft integrally connected at one end thereof to the power piston; a connecting member integrally connected to the other end of the output shaft and slidably disposed inside the hollow cylindrical member, a valve member, a valve return spring for urging and valve member towards the first and second valve seats; and a key member provided between the connecting member and the hollow cylindrical member for allowing relative displacement between the connecting member and the hollow cylindrical member in the first and second directions within a predetermined range.

  14. Ventilation System Effectiveness and Tested Indoor Air Quality Impacts

    SciTech Connect

    Rudd, A.; Bergey, D.

    2014-02-01

    Ventilation system effectiveness testing was conducted at two unoccupied, single-family, detached lab homes at the University of Texas - Tyler. Five ventilation system tests were conducted with various whole-building ventilation systems. Multizone fan pressurization testing characterized building and zone enclosure leakage. PFT testing showed multizone air change rates and interzonal airflow. Cumulative particle counts for six particle sizes, and formaldehyde and other Top 20 VOC concentrations were measured in multiple zones. The testing showed that single-point exhaust ventilation was inferior as a whole-house ventilation strategy. It was inferior because the source of outside air was not direct from outside, the ventilation air was not distributed, and no provision existed for air filtration. Indoor air recirculation by a central air distribution system can help improve the exhaust ventilation system by way of air mixing and filtration. In contrast, the supply and balanced ventilation systems showed that there is a significant benefit to drawing outside air from a known outside location, and filtering and distributing that air. Compared to the Exhaust systems, the CFIS and ERV systems showed better ventilation air distribution and lower concentrations of particulates, formaldehyde and other VOCs. System improvement percentages were estimated based on four System Factor Categories: Balance, Distribution, Outside Air Source, and Recirculation Filtration. Recommended System Factors could be applied to reduce ventilation fan airflow rates relative to ASHRAE Standard 62.2 to save energy and reduce moisture control risk in humid climates. HVAC energy savings were predicted to be 8-10%, or $50-$75/year.

  15. Ventilation System Effectiveness and Tested Indoor Air Quality Impacts

    SciTech Connect

    Rudd, Armin; Bergey, Daniel

    2014-02-01

    In this project, Building America research team Building Science Corporation tested the effectiveness of ventilation systems at two unoccupied, single-family, detached lab homes at the University of Texas - Tyler. Five ventilation system tests were conducted with various whole-building ventilation systems. Multizone fan pressurization testing characterized building and zone enclosure leakage. PFT testing showed multizone air change rates and interzonal airflow. Cumulative particle counts for six particle sizes, and formaldehyde and other Top 20 VOC concentrations were measured in multiple zones. The testing showed that single-point exhaust ventilation was inferior as a whole-house ventilation strategy. This was because the source of outside air was not direct from outside, the ventilation air was not distributed, and no provision existed for air filtration. Indoor air recirculation by a central air distribution system can help improve the exhaust ventilation system by way of air mixing and filtration. In contrast, the supply and balanced ventilation systems showed that there is a significant benefit to drawing outside air from a known outside location, and filtering and distributing that air. Compared to the exhaust systems, the CFIS and ERV systems showed better ventilation air distribution and lower concentrations of particulates, formaldehyde and other VOCs. System improvement percentages were estimated based on four system factor categories: balance, distribution, outside air source, and recirculation filtration. Recommended system factors could be applied to reduce ventilation fan airflow rates relative to ASHRAE Standard 62.2 to save energy and reduce moisture control risk in humid climates. HVAC energy savings were predicted to be 8-10%, or $50-$75/year.

  16. Experimental investigations for uncertainty quantification in brake squeal analysis

    NASA Astrophysics Data System (ADS)

    Renault, A.; Massa, F.; Lallemand, B.; Tison, T.

    2016-04-01

    The aim of this paper is to improve the correlation between the experimental and the numerical prediction of unstable frequencies for automotive brake systems considering uncertainty. First, an experimental quantification of uncertainty and a discussion analysing the contributions of uncertainty to a numerical squeal simulation are proposed. Frequency and transient simulations are performed considering nominal values of model parameters, determined experimentally. The obtained results are compared with those derived from experimental tests to highlight the limitation of deterministic simulations. The effects of the different kinds of uncertainty detected in working conditions of brake system, the pad boundary condition, the brake system material properties and the pad surface topography are discussed by defining different unstable mode classes. Finally, a correlation between experimental and numerical results considering uncertainty is successfully proposed for an industrial brake system. Results from the different comparisons reveal also a major influence of the pad topography and consequently the contact distribution.

  17. PERFORMANCE TESTING OF THE TETRADYNE HIGH SPEED AIR JET SKIMMER

    EPA Science Inventory

    The U.S. Environmental Protection Agency evaluated the performance of the prototype Tetradyne High Speed Air Jet Skimmer at their OHMSETT test facility at Leonardo, New Jersey. The skimmer depends on an air-jet impacting the water surface at an angle and deflecting rapidly moving...

  18. 30 CFR 57.10004 - Brakes.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Brakes. 57.10004 Section 57.10004 Mineral... HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Aerial Tramways § 57.10004 Brakes. Positive-action-type brakes and devices which apply the brakes automatically in the event of a...

  19. 30 CFR 56.10004 - Brakes.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Brakes. 56.10004 Section 56.10004 Mineral... HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Aerial Tramways § 56.10004 Brakes. Positive-action-type brakes and devices which apply the brakes automatically in the event of a...

  20. 49 CFR 229.46 - Brakes: General.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Brakes: General. 229.46 Section 229.46..., DEPARTMENT OF TRANSPORTATION RAILROAD LOCOMOTIVE SAFETY STANDARDS Safety Requirements Brake System § 229.46 Brakes: General. The carrier shall know before each trip that the locomotive brakes and devices...

  1. 30 CFR 57.19004 - Brakes.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Brakes. 57.19004 Section 57.19004 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND....19004 Brakes. Any hoist used to hoist persons shall be equipped with a brake or brakes which shall...

  2. 30 CFR 56.19004 - Brakes.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Brakes. 56.19004 Section 56.19004 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND... Brakes. Any hoist used to hoist persons shall be equipped with a brake or brakes which shall be...

  3. 49 CFR 238.431 - Brake system.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Brake system. 238.431 Section 238.431... Equipment § 238.431 Brake system. (a) A passenger train's brake system shall be capable of stopping the... train is operating under worst-case adhesion conditions. (b) The brake system shall be designed to...

  4. 30 CFR 57.10004 - Brakes.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Brakes. 57.10004 Section 57.10004 Mineral... HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Aerial Tramways § 57.10004 Brakes. Positive-action-type brakes and devices which apply the brakes automatically in the event of a...

  5. 30 CFR 57.19004 - Brakes.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Brakes. 57.19004 Section 57.19004 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND....19004 Brakes. Any hoist used to hoist persons shall be equipped with a brake or brakes which shall...

  6. 30 CFR 56.10004 - Brakes.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Brakes. 56.10004 Section 56.10004 Mineral... HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Aerial Tramways § 56.10004 Brakes. Positive-action-type brakes and devices which apply the brakes automatically in the event of a...

  7. 30 CFR 56.19004 - Brakes.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Brakes. 56.19004 Section 56.19004 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND... Brakes. Any hoist used to hoist persons shall be equipped with a brake or brakes which shall be...

  8. 30 CFR 56.10004 - Brakes.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Brakes. 56.10004 Section 56.10004 Mineral... HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Aerial Tramways § 56.10004 Brakes. Positive-action-type brakes and devices which apply the brakes automatically in the event of a...

  9. 30 CFR 56.10004 - Brakes.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Brakes. 56.10004 Section 56.10004 Mineral... HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Aerial Tramways § 56.10004 Brakes. Positive-action-type brakes and devices which apply the brakes automatically in the event of a...

  10. 49 CFR 238.431 - Brake system.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Brake system. 238.431 Section 238.431... Equipment § 238.431 Brake system. (a) A passenger train's brake system shall be capable of stopping the... train is operating under worst-case adhesion conditions. (b) The brake system shall be designed to...

  11. 30 CFR 57.19004 - Brakes.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Brakes. 57.19004 Section 57.19004 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND....19004 Brakes. Any hoist used to hoist persons shall be equipped with a brake or brakes which shall...

  12. 30 CFR 56.19004 - Brakes.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Brakes. 56.19004 Section 56.19004 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND... Brakes. Any hoist used to hoist persons shall be equipped with a brake or brakes which shall be...

  13. 30 CFR 57.10004 - Brakes.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Brakes. 57.10004 Section 57.10004 Mineral... HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Aerial Tramways § 57.10004 Brakes. Positive-action-type brakes and devices which apply the brakes automatically in the event of a...

  14. 30 CFR 57.19004 - Brakes.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Brakes. 57.19004 Section 57.19004 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND....19004 Brakes. Any hoist used to hoist persons shall be equipped with a brake or brakes which shall...

  15. 30 CFR 56.19004 - Brakes.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Brakes. 56.19004 Section 56.19004 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND... Brakes. Any hoist used to hoist persons shall be equipped with a brake or brakes which shall be...

  16. 30 CFR 57.10004 - Brakes.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Brakes. 57.10004 Section 57.10004 Mineral... HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Aerial Tramways § 57.10004 Brakes. Positive-action-type brakes and devices which apply the brakes automatically in the event of a...

  17. 30 CFR 57.19004 - Brakes.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Brakes. 57.19004 Section 57.19004 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND....19004 Brakes. Any hoist used to hoist persons shall be equipped with a brake or brakes which shall...

  18. 30 CFR 56.19004 - Brakes.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Brakes. 56.19004 Section 56.19004 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND... Brakes. Any hoist used to hoist persons shall be equipped with a brake or brakes which shall be...

  19. 30 CFR 56.10004 - Brakes.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Brakes. 56.10004 Section 56.10004 Mineral... HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Aerial Tramways § 56.10004 Brakes. Positive-action-type brakes and devices which apply the brakes automatically in the event of a...

  20. 49 CFR 238.431 - Brake system.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Brake system. 238.431 Section 238.431... Equipment § 238.431 Brake system. (a) A passenger train's brake system shall be capable of stopping the... train is operating under worst-case adhesion conditions. (b) The brake system shall be designed to...

  1. 49 CFR 238.431 - Brake system.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Brake system. 238.431 Section 238.431... Equipment § 238.431 Brake system. (a) A passenger train's brake system shall be capable of stopping the... train is operating under worst-case adhesion conditions. (b) The brake system shall be designed to...

  2. 30 CFR 57.10004 - Brakes.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Brakes. 57.10004 Section 57.10004 Mineral... HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Aerial Tramways § 57.10004 Brakes. Positive-action-type brakes and devices which apply the brakes automatically in the event of a...

  3. Development of an Ultrasonic Brake

    NASA Astrophysics Data System (ADS)

    Koyama, Tatsuya; Takemura, Kenjiro; Maeno, Takashi

    In the present paper, a newly developed ultrasonic brake is proposed. The ultrasonic brake can solve problems of conventional passive elements, such as time delay, instability, and large size, by using unique characteristics of ultrasonic motor, as fast response, silent motion, and non-magnetic feature. It can also be designed to be smaller than conventional elements due to its simple structure. The brake locks or releases the rotor by use of ultrasonic levitation phenomenon. First, we have designed the structure of the ultrasonic brake using an equation of ultrasonic levitation phenomenon, results from structural analysis and finite element (FE) analysis of piezoelectric material of the vibrator. Then we have manufactured the ultrasonic brake and have conducted a driving experiment. Finally, we have demonstrated that the maximum levitation force is around 40 N and the friction torque of the ultrasonic brake is up to 0.38 Nm. Moreover, we have confirmed that both response time and torque/inertia ratio of the ultrasonic brake are much more superior to the conventional ones.

  4. Pulsar braking: magnetodipole vs. wind

    NASA Astrophysics Data System (ADS)

    Tong, Hao

    2016-01-01

    Pulsars are good clocks in the universe. One fundamental question is that why they are good clocks? This is related to the braking mechanism of pulsars. Nowadays pulsar timing is done with unprecedented accuracy. More pulsars have braking indices measured. The period derivative of intermittent pulsars and magnetars can vary by a factor of several. However, during pulsar studies, the magnetic dipole braking in vacuum is still often assumed. It is shown that the fundamental assumption of magnetic dipole braking (vacuum condition) does not exist and it is not consistent with the observations. The physical torque must consider the presence of the pulsar magnetosphere. Among various efforts, the wind braking model can explain many observations of pulsars and magnetars in a unified way. It is also consistent with the up-to-date observations. It is time for a paradigm shift in pulsar studies: from magnetic dipole braking to wind braking. As one alternative to the magnetospheric model, the fallback disk model is also discussed.

  5. Real-Time Dynamic Brake Assessment Proof of Concept Final Report

    SciTech Connect

    Lascurain, Mary Beth; Franzese, Oscar; Capps, Gary J

    2011-11-01

    This proof-of-concept research was performed to explore the feasibility of using real-world braking data from commercial motor vehicles to make a diagnosis of brake condition similar to that of the performance-based brake tester (PBBT). This was done by determining the relationship between pressure and brake force (P-BF), compensating for the gross vehicle weight (GVW). The nature of this P-BF relationship (e.g., low braking force for a given brake application pressure) may indicate brake system problems. In order to determine the relationship between brake force and brake application pressure, a few key parameters of duty cycle information were collected. Because braking events are often brief, spanning only a few seconds, a sample rate of 10 Hz was needed. The algorithm under development required brake application pressure and speed (from which deceleration was calculated). Accurate weight estimation was also needed to properly derive the braking force from the deceleration. In order to ensure that braking force was the predominant factor in deceleration for the segments of data used in analysis, the data was screened for grade as well. Also, the analysis needed to be based on pressures above the crack pressure. The crack pressure is the pressure below which the individual brakes are not applied due the nature of the mechanical system. This value, which may vary somewhat from one wheel end to another, is approximately 10 psi. Therefore, only pressures 15 psi and above were used in the analysis. The Department of Energy s Medium Truck Duty Cycle research has indicated that under the real-world circumstances of the test vehicle brake pressures of up to approximately 30 psi can be expected. Several different types of data were collected during the testing task of this project. Constant-pressure stopping tests were conducted at several combinations of brake application pressure (15, 20, 25, and 30 psi), load conditions (moderately and fully laden), and speeds (20 and

  6. Transient switching control strategy from regenerative braking to anti-lock braking with a semi-brake-by-wire system

    NASA Astrophysics Data System (ADS)

    Li, Liang; Li, Xujian; Wang, Xiangyu; Liu, Yahui; Song, Jian; Ran, Xu

    2016-02-01

    Regenerative braking is an important technology in improving fuel economy of an electric vehicle (EV). However, additional motor braking will change the dynamic characteristics of the vehicle, leading to braking instability, especially when the anti-lock braking system (ABS) is triggered. In this paper, a novel semi-brake-by-wire system, without the use of a pedal simulator and fail-safe device, is proposed. In order to compensate for the hysteretic characteristics of the designed brake system while ensure braking reliability and fuel economy when the ABS is triggered, a novel switching compensation control strategy using sliding mode control is brought forward. The proposed strategy converts the complex coupling braking process into independent control of hydraulic braking and regenerative braking, through which a balance between braking performance, braking reliability, braking safety and fuel economy is achieved. Simulation results show that the proposed strategy is effective and adaptable in different road conditions while the large wheel slip rate is triggered during a regenerative braking course. The research provides a new possibility of low-cost equipment and better control performance for the regenerative braking in the EV and the hybrid EV.

  7. Evaluation of unsaturated zone air permeability through pneumatic tests

    USGS Publications Warehouse

    Baehr, Arthur L.; Hult, Marc F.

    1991-01-01

    Predicting the steady state distribution of air pressure in the unsaturated zone resulting from a pneumatic test provides a method for determining air-phase permeability. This technique is analogous to the inverse problem of well hydraulics; however, air flow is more complicated than ground water flow because of air compressibility, the Klinkenberg effect, variations in air density and viscosity that result from temperature fluctuations in the unsaturated zone and the possibility of inducing water movement during the pneumatic test. An analysis of these complicating factors reveals that, when induced water movement can be neglected, a linear version of the airflow equation can provide an appropriate approximation for the purpose of determining air-phase permeability. Two analytical solutions for steady state, two-dimensional, axisymmetric airflow to a single well partially screened in the unsaturated zone are developed. One solution applies where there is a stratum of relatively low air permeability, separating the stratum in which the well is completed, from the atmosphere. The other solution applies where there is no separating stratum between the domain and atmosphere. In both situations the water table forms the lower horizontal boundary. Applications of both solutions to determine air permeability from data collected during pneumatic tests are presented.

  8. NASA diagonal-braked test vehicle evaluation of traction characteristics of grooved and ungrooved runway surfaces at Miami International Airport, Miami, Florida, 8-9 May 1973

    NASA Technical Reports Server (NTRS)

    Horne, W. B.

    1977-01-01

    Two runways were evaluated under artificially wetted conditions with the NASA diagonal-braked vehicle (DBV). Results of the evaluation which included a pavement drainage analysis, a pavement skid resistance analysis, and a DBV wet/dry stopping distance ratio analysis indicated that the ungrooved runway surfaces had poor water drainage characteristics and poor skid resistance under wet conditions at high speeds especially in rubbercoated areas of the runways. Grooving runways to a transverse 1-1/4 x 1/4 x 1/4 inch pattern greatly improved both the water drainage and pavement skid resistance capability of these asphaltic concrete surfaces.

  9. Study on the dynamic characteristics of a high frequency brake based on giant magnetostrictive material

    NASA Astrophysics Data System (ADS)

    Xu, Ai Qun

    2016-06-01

    In order to meet the requirements of rapid and smooth braking, high-frequency braking using a giant magnetostrictive actuator is proposed, which can solve the problems in hydraulic braking, such as, it leaks easily, catches fire easily, is difficult to find failures, high cost on maintenance and repairing, etc. The main factors affecting the force of a high-frequency braking actuator are emphatically analyzed, the brakes dynamic model is established and a performance testing device for high frequency braking is constructed based on LabVIEW. The output force of the actuator increases with the excitation current of the driving coil increasing, and the increased multiple of the output force is greater than that of the excitation current; the range of the actuator force amplitude is 121.63 N ∼ 158.14 N, which changes little, while excitation frequency changes between 200 Hz ∼ 1000 Hz. In a minor range of pre-stress, the output force decreases with an increase in the axial pre-stress of the giant magnetostrictive rod, but is not obvious. It is known by finite element simulation analysis that high-frequency braking shortens the braking displacement and time effectively, which proves the feasibility and effectiveness of high frequency braking. Theoretical analysis and experimental results indicate that the output force of the actuator changes at the same frequency with excitation current; it is controllable and its mechanical properties meet the requirements of high frequency braking.

  10. Regenerative braking device

    DOEpatents

    Hoppie, Lyle O.

    1982-01-12

    Disclosed are several embodiments of a regenerative braking device for an automotive vehicle. The device includes a plurality of rubber rollers (24, 26) mounted for rotation between an input shaft (14) connectable to the vehicle drivetrain and an output shaft (16) which is drivingly connected to the input shaft by a variable ratio transmission (20). When the transmission ratio is such that the input shaft rotates faster than the output shaft, the rubber rollers are torsionally stressed to accumulate energy, thereby slowing the vehicle. When the transmission ratio is such that the output shaft rotates faster than the input shaft, the rubber rollers are torsionally relaxed to deliver accumulated energy, thereby accelerating or driving the vehicle.

  11. DUS II SOIL GAS SAMPLING AND AIR INJECTION TEST RESULTS

    SciTech Connect

    Noonkester, J.; Jackson, D.; Jones, W.; Hyde, W.; Kohn, J.; Walker, R.

    2012-09-20

    Soil vapor extraction (SVE) and air injection well testing was performed at the Dynamic Underground Stripping (DUS) site located near the M-Area Settling Basin (referred to as DUS II in this report). The objective of this testing was to determine the effectiveness of continued operation of these systems. Steam injection ended on September 19, 2009 and since this time the extraction operations have utilized residual heat that is present in the subsurface. The well testing campaign began on June 5, 2012 and was completed on June 25, 2012. Thirty-two (32) SVE wells were purged for 24 hours or longer using the active soil vapor extraction (ASVE) system at the DUS II site. During each test five or more soil gas samples were collected from each well and analyzed for target volatile organic compounds (VOCs). The DUS II site is divided into four parcels (see Figure 1) and soil gas sample results show the majority of residual VOC contamination remains in Parcel 1 with lesser amounts in the other three parcels. Several VOCs, including tetrachloroethylene (PCE) and trichloroethylene (TCE), were detected. PCE was the major VOC with lesser amounts of TCE. Most soil gas concentrations of PCE ranged from 0 to 60 ppmv with one well (VEW-22A) as high as 200 ppmv. Air sparging (AS) generally involves the injection of air into the aquifer through either vertical or horizontal wells. AS is coupled with SVE systems when contaminant recovery is necessary. While traditional air sparging (AS) is not a primary component of the DUS process, following the cessation of steam injection, eight (8) of the sixty-three (63) steam injection wells were used to inject air. These wells were previously used for hydrous pyrolysis oxidation (HPO) as part of the DUS process. Air sparging is different from the HPO operations in that the air was injected at a higher rate (20 to 50 scfm) versus HPO (1 to 2 scfm). . At the DUS II site the air injection wells were tested to determine if air sparging affected

  12. Brake Stops Both Rotation And Translation

    NASA Technical Reports Server (NTRS)

    Allred, Johnny W.; Fleck, Vincent J., Jr.

    1995-01-01

    Combination of braking and positioning mechanisms allows both rotation and translation before brake engaged. Designed for use in positioning model airplane in wind tunnel. Modified version used to position camera on tripod. Brake fast and convenient to use; contains single actuator energizing braking actions against both rotation and translation. Braking actuator electric, but pneumatic actuator could be used instead. Compact and lightweight, applies locking forces close to load, and presents minimal cross section to airflow.

  13. IMPROVED TEST METHODS FOR ELECTRONIC AIR CLEANERS

    EPA Science Inventory

    The objective of this project was to develop a fractional filtration efficiency test protocol for residential electrostatic precipitators (ESPs) that avoids the limitations of the ASHRAE 52.2 method. Specifically, the objectives were to a) determine the change in efficiency that ...

  14. Laboratory Performance Testing of Residential Window Air Conditioners

    SciTech Connect

    Winkler, J.; Booten, C.; Christensen, D.; Tomerlin, J.

    2013-03-01

    Window air conditioners are the dominant cooling product for residences, in terms of annual unit sales. They are inexpensive, portable and can be installed by the owner. For this reason, they are an attractive solution for supplemental cooling, for retrofitting air conditioning into a home which lacks ductwork, and for renters. Window air conditioners for sale in the United States are required to meet very modest minimum efficiency standards. Four window air conditioners' performance were tested in the Advanced HVAC Systems Laboratory on NREL's campus in Golden, CO. In order to separate and study the refrigerant system's performance, the unit's internal leakage pathways, the unit's fanforced ventilation, and the leakage around the unit resulting from installation in a window, a series of tests were devised that focused on each aspect of the unit's performance. These tests were designed to develop a detailed performance map to determine whole-house performance in different climates. Even though the test regimen deviated thoroughly from the industry-standard ratings test, the results permit simple calculation of an estimated rating for both capacity and efficiency that would result from a standard ratings test. Using this calculation method, it was found that the three new air conditioners' measured performance was consistent with their ratings. This method also permits calculation of equivalent SEER for the test articles. Performance datasets were developed across a broad range of indoor and outdoor operating conditions, and used them to generate performance maps.

  15. Brake control system modification, augmentor Wing Jet STOL Research Airplane (AWJSRA)

    NASA Technical Reports Server (NTRS)

    Amberg, R. L.; Arline, J. A.; Jenny, R. W.

    1974-01-01

    The braking system for a short takeoff aircraft is discussed and the deficiencies are described. The installation of a Boeing 727 aircraft brake system was made to correct the deficiencies. Tests of the modified system were conducted using an analog computer/hardware simulator. Actual performance tests were conducted and the characteristics of the system were satisfactory.

  16. Variable ratio regenerative braking device

    DOEpatents

    Hoppie, Lyle O.

    1981-12-15

    Disclosed is a regenerative braking device (10) for an automotive vehicle. The device includes an energy storage assembly (12) having a plurality of rubber rollers (26, 28) mounted for rotation between an input shaft (36) and an output shaft (42), clutches (38, 46) and brakes (40, 48) associated with each shaft, and a continuously variable transmission (22) connectable to a vehicle drivetrain and to the input and output shafts by the respective clutches. The rubber rollers are torsionally stressed to accumulate energy from the vehicle when the input shaft is clutched to the transmission while the brake on the output shaft is applied, and are torsionally relaxed to deliver energy to the vehicle when the output shaft is clutched to the transmission while the brake on the input shaft is applied. The transmission ratio is varied to control the rate of energy accumulation and delivery for a given rotational speed of the vehicle drivetrain.

  17. HESTIA Phase I Test Results: The Air Revitalization System

    NASA Technical Reports Server (NTRS)

    Wright, Sarah E.; Hansen, Scott W.

    2016-01-01

    In any human spaceflight mission, a number of Environmental Control & Life Support System (ECLSS) technologies work together to provide the conditions astronauts need to live healthily, productively, and comfortably in space. In a long-duration mission, many of these ECLSS technologies may use materials supplied by In-Situ Resource Utilization (ISRU), introducing more interactions between systems. The Human Exploration Spacecraft Test-bed for Integration & Advancement (HESTIA) Project aims to create a test-bed to evaluate ECLSS and ISRU technologies and how they interact in a high-fidelity, closed-loop, human-rated analog habitat. Air purity and conditioning are essential components within any ECLSS and for HESTIA's first test they were achieved with the Air Revitalization System (ARS) described below. The ARS provided four essential functions to the test-bed chamber: cooling the air, removing humidity from the air, removing trace contaminants, and scrubbing carbon dioxide (CO2) from the air. In this case, the oxygen supply function was provided by ISRU. In the current configuration, the ARS is a collection of different subsystems. A fan circulates the air, while a condensing heat exchanger (CHX) pulls humidity out of the air. A Trace Contaminant Removal System (TCRS) filters the air of potentially harmful contaminants. Lastly, a Reactive Plastic Lithium Hydroxide (RP-LiOH) unit removes CO2 from the breathing air. During the HESTIA Phase I test in September 2015, the ARS and its individual components each functioned as expected, although further analysis is underway. During the Phase I testing and in prior bench-top tests, the energy balance of heat removed by the CHX was not equal to the cooling it received. This indicated possible instrument error and therefore recalibration of the instruments and follow-up testing is planned in 2016 to address the issue. The ARS was tested in conjunction with two other systems: the Human Metabolic Simulator (HMS) and the

  18. Slowly braked, rotating neutron stars

    NASA Technical Reports Server (NTRS)

    Sato, H.

    1975-01-01

    A slowly braked, rotating neutron star is believed to be a star which rapidly rotates, has no nebula, is nonpulsing, and has a long initial braking time of ten thousand to a million years because of a low magnetic field. Such an object might be observable as an extended weak source of infrared or radio wave radiation due to the scattering of low-frequency strong-wave photons by accelerated electrons. If these objects exist abundantly in the Galaxy, they would act as sources of relatively low-energy cosmic rays. Pulsars (rapidly braked neutron stars) are shown to have difficulties in providing an adequate amount of cosmic-ray matter, making these new sources seem necessary. The possibility that the acceleration mechanism around a slowly braked star may be not a direct acceleration by the strong wave but an acceleration due to plasma turbulence excited by the strong wave is briefly explored. It is shown that white dwarfs may also be slowly braked stars with braking times longer than 3.15 million years.

  19. Fabrication of VB2/air cells for electrochemical testing.

    PubMed

    Stuart, Jessica; Lopez, Ruben; Lau, Jason; Li, Xuguang; Waje, Mahesh; Mullings, Matthew; Rhodes, Christopher; Licht, Stuart

    2013-01-01

    A technique to investigate the properties and performance of new multi-electron metal/air battery systems is proposed and presented. A method for synthesizing nanoscopic VB2 is presented as well as step-by-step procedure for applying a zirconium oxide coating to the VB2 particles for stabilization upon discharge. The process for disassembling existing zinc/air cells is shown, in addition construction of the new working electrode to replace the conventional zinc/air cell anode with a the nanoscopic VB2 anode. Finally, discharge of the completed VB2/air battery is reported. We show that using the zinc/air cell as a test bed is useful to provide a consistent configuration to study the performance of the high-energy high capacity nanoscopic VB2 anode. PMID:23962835

  20. Fabrication of VB2/Air Cells for Electrochemical Testing

    PubMed Central

    Stuart, Jessica; Lopez, Ruben; Lau, Jason; Li, Xuguang; Waje, Mahesh; Mullings, Matthew; Rhodes, Christopher; Licht, Stuart

    2013-01-01

    A technique to investigate the properties and performance of new multi-electron metal/air battery systems is proposed and presented. A method for synthesizing nanoscopic VB2 is presented as well as step-by-step procedure for applying a zirconium oxide coating to the VB2 particles for stabilization upon discharge. The process for disassembling existing zinc/air cells is shown, in addition construction of the new working electrode to replace the conventional zinc/air cell anode with a the nanoscopic VB2 anode. Finally, discharge of the completed VB2/air battery is reported. We show that using the zinc/air cell as a test bed is useful to provide a consistent configuration to study the performance of the high-energy high capacity nanoscopic VB2 anode. PMID:23962835

  1. Airline Transport Pilot-Airplane (Air Carrier) Written Test Guide.

    ERIC Educational Resources Information Center

    Federal Aviation Administration (DOT), Washington, DC. Flight Standards Service.

    Presented is information useful to applicants who are preparing for the Airline Transport Pilot-Airplane (Air Carrier) Written Test. The guide describes the basic aeronautical knowledge and associated requirements for certification, as well as information on source material, instructions for taking the official test, and questions that are…

  2. Air Force Officer Qualifying Test Form O: Development and Standardization.

    ERIC Educational Resources Information Center

    Rogers, Deborah L.; And Others

    This report presents the rationale, development, and standardization of the Air Force Officer Qualifying Test (AFOQT) Form O. The test is used to select individuals for officer commissioning programs, and candidates for pilot and navigator training. Form O contains 380 items organized in 16 subtests. All items are administered in a single test…

  3. Longitudinal wheel slip during ABS braking

    NASA Astrophysics Data System (ADS)

    Hartikainen, Lassi; Petry, Frank; Westermann, Stephan

    2015-02-01

    Anti-lock braking system (ABS) braking tests with two subcompact passenger cars were performed on dry and wet asphalt, as well as on snow and ice surfaces. The operating conditions of the tyres in terms of wheel slip were evaluated using histograms of the wheel slip data. The results showed different average slip levels for different road surfaces. It was also found that changes in the tyre tread stiffness affected the slip operating range through a modification of the slip value at which the maximum longitudinal force is achieved. Variation of the tyre footprint length through modifications in the inflation pressure affected the slip operating range as well. Differences in the slip distribution between vehicles with different brake controllers were also observed. The changes in slip operating range in turn modified the relative local sliding speeds between the tyre and the road. The results highlight the importance of the ABS controller's ability to adapt to changing slip-force characteristics of tyres and provide estimates of the magnitude of the effects of different tyre and road operating conditions.

  4. Thermal Modeling of Disc Brake Rotor in Frictional Contact

    NASA Astrophysics Data System (ADS)

    Ali, Belhocine; Ghazaly, Nouby Mahdi

    2013-01-01

    Safety aspect in automotive engineering has been considered as a number one priority in development of new vehicle. Each single system has been studied and developed in order to meet safety requirement. Instead of having air bag, good suspension systems, good handling and safe cornering, there is one most critical system in the vehicle which is brake systems. The objective of this work is to investigate and analyze the temperature distribution of rotor disc during braking operation using ANSYS Multiphysics. The work uses the finite element analysis techniques to predict the temperature distribution on the full and ventilated brake disc and to identify the critical temperature of the rotor. The analysis also gives us, the heat flux distribution for the two discs.

  5. Report of the Building 9207 air bag test

    SciTech Connect

    Huff, T.E.; Fricke, K.E.; Jones, W.D.

    1992-12-01

    As part of a major testing program now underway at the Department of Energy`s (DOE) Oak Ridge Y-12 Plant, managed by Martin Marietta Energy Systems, Inc. (MMES), a full-scale air bag test was conducted in Building 9207. The test program, supported and managed by the Center for Natural Phenomena Engineering (CNPE), is intended to determine the stiffness and strength of unreinforced hollow clay tile walls (HCTVS) in order to more accurately analyze and predict the response of buildings containing these type of walls, especially when subjected to seismic and high wind loadings. The air bag test was a very large undertaking that started more than a year before the test was actually performed. Preparation for the test included the following activities: (1) preparation of the wall and the adjacent building areas; (2) design and field fabrication of test supporting structures; (3) procurement of equipment and instrumentation; (4) development of supporting test procedures and checklists; (5) installation of over seventy linear variable differential transformers (LVDTs) and strain gages; (6) development of computer programs for use in the data acquisition systems; (7) extensive review into the existing engineering literature; (8) discussions with researchers with prior experience performing air bag tests; (9) coordination with the building operators; (10) plant safety reviews; and (11) dry runs of the test itself.

  6. Compression relief engine brake

    SciTech Connect

    Meneely, V.A.

    1987-10-06

    A compression relief brake is described for four cycle internal-combustion engines, comprising: a pressurized oil supply; means for selectively pressurizing a hydraulic circuit with oil from the oil supply; a master piston and cylinder communicating with a slave piston and cylinder via the hydraulic circuit; an engine exhaust valve mechanically coupled to the engine and timed to open during the exhaust cycle of the engine the exhaust valve coupled to the slave piston. The exhaust valve is spring-based in a closed state to contact a valve seat; a sleeve frictionally and slidably disposed within a cavity defined by the slave piston which cavity communicates with the hydraulic circuit. When the hydraulic circuit is selectively pressurized and the engine is operating the sleeve entraps an incompressible volume of oil within the cavity to generate a displacement of the slave piston within the slave cylinder, whereby a first gap is maintained between the exhaust valve and its associated seat; and means for reciprocally activating the master piston for increasing the pressure within the previously pressurized hydraulic circuit during at least a portion of the expansion cycle of the engine whereby a second gap is reciprocally maintained between the exhaust valve and its associated seat.

  7. Testing Theoretical Models of Magnetic Damping Using an Air Track

    ERIC Educational Resources Information Center

    Vidaurre, Ana; Riera, Jaime; Monsoriu, Juan A.; Gimenez, Marcos H.

    2008-01-01

    Magnetic braking is a long-established application of Lenz's law. A rigorous analysis of the laws governing this problem involves solving Maxwell's equations in a time-dependent situation. Approximate models have been developed to describe different experimental results related to this phenomenon. In this paper we present a new method for the…

  8. Design of a squeeze film magnetorheological brake considering compression enhanced shear yield stress of magnetorheological fluid

    NASA Astrophysics Data System (ADS)

    Sarkar, C.; Hirani, H.

    2013-02-01

    A magnetorheological brake, consisting of rotating disks immersed in a MR fluid and enclosed in an electromagnet, is proposed to replace the conventional heavy weight low response hydraulic disk brake. The frictional characteristics of the proposed brake can be controlled by regulating the yield stress of the MR fluid as function of magnetic field and normal compressive force. The controllable yield stress retards the surfaces of rotating disks, thus MR fluid can be used as a brake lining material. The present research work attempts designing a squeeze film MR brake by accounting compression enhanced shear yield stress of magnetorheological fluid. Theoretical calculations indicate that the estimated braking torque of the six plate squeeze film MR brake, under compression, is in the order of 600Nm. To validate the theoretical design and its findings, a prototype of single-plate squeeze film MR disk brake has been developed. Experimental test setup helps to illustrate braking torque under different control currents (0.0 to 1.25 A).

  9. WHY DO THE BRAKING INDICES OF PULSARS SPAN A RANGE OF MORE THAN 100 MILLIONS?

    SciTech Connect

    Zhang Shuangnan; Xie Yi

    2012-12-20

    Here we report that the observed braking indices of the 366 pulsars in the sample of Hobbs et al. range from about -10{sup 8} to about +10{sup 8} and are significantly correlated with their characteristic ages. Using the model of magnetic field evolution we developed previously based on the same data, we derive an analytical expression for the braking index which agrees with all the observed statistical properties of the braking indices of the pulsars in the sample of Hobbs et al. Our model is, however, incompatible with the previous interpretation that magnetic field growth is responsible for the small values of braking indices (<3) observed for ''baby'' pulsars with characteristic ages of less than 2 Multiplication-Sign 10{sup 3} yr. We find that the ''instantaneous'' braking index of a pulsar may be different from the ''averaged'' braking index obtained from fitting the data over a certain time span. The close match between our model-predicted ''instantaneous'' braking indices and the observed ''averaged'' braking indices suggests that the time spans used previously are usually smaller than or comparable to their magnetic field oscillation periods. Our model can be tested with the existing data by calculating the braking index as a function of the time span for each pulsar. In doing so, one can obtain for each pulsar all the parameters in our magnetic field evolution model, and may be able to improve the sensitivity of using pulsars to detect gravitational waves.

  10. Why Do the Braking Indices of Pulsars Span a Range of More Than 100 Millions?

    NASA Astrophysics Data System (ADS)

    Zhang, Shuang-Nan; Xie, Yi

    2012-12-01

    Here we report that the observed braking indices of the 366 pulsars in the sample of Hobbs et al. range from about -108 to about +108 and are significantly correlated with their characteristic ages. Using the model of magnetic field evolution we developed previously based on the same data, we derive an analytical expression for the braking index which agrees with all the observed statistical properties of the braking indices of the pulsars in the sample of Hobbs et al. Our model is, however, incompatible with the previous interpretation that magnetic field growth is responsible for the small values of braking indices (<3) observed for "baby" pulsars with characteristic ages of less than 2 × 103 yr. We find that the "instantaneous" braking index of a pulsar may be different from the "averaged" braking index obtained from fitting the data over a certain time span. The close match between our model-predicted "instantaneous" braking indices and the observed "averaged" braking indices suggests that the time spans used previously are usually smaller than or comparable to their magnetic field oscillation periods. Our model can be tested with the existing data by calculating the braking index as a function of the time span for each pulsar. In doing so, one can obtain for each pulsar all the parameters in our magnetic field evolution model, and may be able to improve the sensitivity of using pulsars to detect gravitational waves.

  11. The Air Force modular automatic test equipment (mate) maintenance concepts

    NASA Astrophysics Data System (ADS)

    Stout, J.; Persans, D.; Caporale, J.

    The Air Force has developed the Modular Automatic Test Equipment (MATE) system as a disciplined approach to the definition, acquisition, and support of automatic test equipment. The system is expressed in a series of guides regarding the hardware, computer program, human factors, and documentation required to implement the considered approach. The present investigation is concerned with the facet of the guidelines which addresses the MATE maintenance concepts. Attention is given to maintenance problems in the field, a MATE system maintenance concept overview, maintenance-oriented tests, integrated diagnostics, the MATE system operational/confidence test scenario, and a MATE system optional self-test.

  12. Development and test of the Atmospheric Infrared Sounder (AIRS)

    NASA Astrophysics Data System (ADS)

    Morse, Paul G.; Bates, Jerry C.; Miller, Christopher R.; Chahine, Moustafa T.; O'Callaghan, Fred; Aumann, Hartmut H.; Karnik, Avinash R.

    1999-12-01

    The Atmospheric Infrared Sounder (AIRS) has been developed for the NASA Earth Observing System (EOS) program for a scheduled launch on the EOS PM-1 spacecraft in December 2000. AIRS, working in concert with complementary microwave instrumentation on EOS PM-1 is designed to provide both new and more accurate data about the atmosphere, land and oceans for application to NASA climate studies and NOAA and DOD weather prediction. Among the important parameters to be derived from AIRS observations are atmospheric temperature profiles with an average accuracy of 1 K in 1 kilometer (km) layers in the troposphere, humidity profiles to 10% accuracy and surface temperatures with an average accuracy of 0.5 K. The AIRS measurement technique is based on passive IR remote sensing using a precisely calibrated, high spectral resolution grating spectrometer operating in the 3.7 - 15.4 micrometer region. The instrument concept uses a passively cooled multi- aperture echelle array spectrometer approach in combination with advanced state of the art focal plane and cryogenic refrigerator technology to achieve unparalleled performance capability in a practical long life configuration. The AIRS instrument, which has been under development since 1991, has been fully integrated and has completed successfully a comprehensive performance verification program. Performance verification included thermal vacuum testing, environmental qualification and a full range of spatial, spectral and radiometric calibrations, which have demonstrated outstanding spectrometric performance. This paper provides a brief overview of the AIRS mission and instrument design along with key results from the test program.

  13. Test results of lithium pool-air reaction suppression systems

    SciTech Connect

    Jeppson, D.W.

    1987-02-01

    Engineered reaction suppression systems were demonstrated to be effective in suppressing lithium pool-air reactions for lithium quantities up to 100 kg. Lithium pool-air reaction suppression system tests were conducted to evaluate suppression system effectiveness for potential use in fusion facilities in mitigating consequences of postulated lithium spills. Small-scale perforated and sacrificial cover plate suppression systems with delayed inert gas purging proved effective in controlling the lithium-air interaction for lithium quantities near 15 kg at initial temperatures up to 450/sup 0/C. A large-scale suppression system with a sacrificial cover, a diverter plate, an inert gas atmosphere, and remotely retrievable catch pans proved effective in controlling lithium pool-air interaction for a 100-kg lithium discharge at an initial temperature of 550/sup 0/C. This suppression system limited the maximum pool temperature to about 600/sup 0/C less than that expected for a similar lithium pool-air reaction without a suppression system. Lithium aerosol release from this large-scale suppression system was a factor of about 10,000 less than that expected for a lithium pool-air reaction with no suppression system. Remote retrieval techniques for lithium cleanup, such as (1) in-place lithium siphoning and overhead crane dismantling, and (2) lithium catch pan removal by use of an overhead crane, were demonstrated as part of this large-scale test.

  14. Validity of cycle test in air compared to underwater cycling.

    PubMed

    Almeling, M; Schega, L; Witten, F; Lirk, P; Wulf, K

    2006-01-01

    According to international guidelines, fitness to dive is generally assessed using a bicycle stress test (BST) in air. To date, there is no study explicitly addressing the question whether the results of a BST in air really predict performance status under water. Therefore, the aim of the present study was twofold: first, to design an experimental setting allowing the examination of physical performance status under water, and second, to examine whether there is an association of response to exercise in air compared to exercise under water using self contained underwater breathing apparatus (SCUBA). We constructed and evaluated a measurement technique for a bicycle ergometry and for gas analysis under water. Part of the work was the development of a new valve system which allowed to collect the exhaled air in total and to transport it to the spirometer next to the pool. Twenty-eight healthy male divers underwent a BST. Compared to a given workload in air, gross capacity decreased significantly by about 50% underwater. High performance in air was associated with a high performance underwater. The examinations were carried out without any complications. In conclusion, our experimental setting allowed the safe and reliable examination of physical performance status under water. First results indicate that the results of a BST in air correlate well with the cardio-circulatory performance status underwater. A subsequent study with a larger sample size will enable us to more precisely model this correlation. PMID:16602256

  15. 49 CFR 571.105 - Standard No. 105; Hydraulic and electric brake systems.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... word, words or abbreviation, in accordance with the requirements of Standard No. 101 (49 CFR 571.101... of brake fluid as specified in 49 CFR 571.116, e.g., “DOT 3”). The lettering shall be— (a... stability and control during braking tests) are conducted on a 12-foot-wide, level roadway, having a...

  16. 49 CFR 571.105 - Standard No. 105; Hydraulic and electric brake systems.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... word, words or abbreviation, in accordance with the requirements of Standard No. 101 (49 CFR 571.101... of brake fluid as specified in 49 CFR 571.116, e.g., “DOT 3”). The lettering shall be— (a... stability and control during braking tests) are conducted on a 12-foot-wide, level roadway, having a...

  17. Theoretical and numerical analysis of the corneal air puff test

    NASA Astrophysics Data System (ADS)

    Simonini, Irene; Angelillo, Maurizio; Pandolfi, Anna

    2016-08-01

    Ocular analyzers are used in the current clinical practice to estimate, by means of a rapid air jet, the intraocular pressure and other eye's parameters. In this study, we model the biomechanical response of the human cornea to the dynamic test with two approaches. In the first approach, the corneal system undergoing the air puff test is regarded as a harmonic oscillator. In the second approach, we use patient-specific geometries and the finite element method to simulate the dynamic test on surgically treated corneas. In spite of the different levels of approximation, the qualitative response of the two models is very similar, and the most meaningful results of both models are not significantly affected by the inclusion of viscosity of the corneal material in the dynamic analysis. Finite element calculations reproduce the observed snap-through of the corneal shell, including two applanate configurations, and compare well with in vivo images provided by ocular analyzers, suggesting that the mechanical response of the cornea to the air puff test is actually driven only by the elasticity of the stromal tissue. These observations agree with the dynamic characteristics of the test, since the frequency of the air puff impulse is several orders of magnitude larger than the reciprocal of any reasonable relaxation time for the material, downplaying the role of viscosity during the fast snap-through phase.

  18. Air- coupled ultrasonic testing of CFRP rods by means of guided waves

    NASA Astrophysics Data System (ADS)

    Kažys, Rymantas; Raišutis, Renaldas; Žukauskas, Egidijus; Mažeika, Liudas; Vladišauskas, Alfonsas

    2010-01-01

    One of the most important parts of the gliders is a lightweight longeron reinforcement made of carbon fibre reinforced plastics (CFRP) rods. These small diameter (a few millimetres) rods during manufacturing are glued together in epoxy filled matrix in order to build the arbitrary spar profile. However, the defects presenting in the rods such as brake of fibres, lack of bonding, reduction of density affect essentially the strength of the construction and are very complicated in repairing. Therefore, appropriate non-destructive testing techniques of carbon fibber rods should be applied before gluing them together. The objective of the presented work was development of NDT technique of CFRP rods used for aerospace applications, which is based on air- coupled excitation/reception of guided waves. The regularities of ultrasonic guided waves propagating in both circular and rectangular cross-section CFRP rods immersed into water were investigated and it was shown that the guided waves propagating along sample of the rod create leaky waves which are radiated into a surrounding medium. The ultrasonic receiver scanned over the rod enables to pick-up the leaky waves and to determine the non-uniformities of propagation caused by the defects. Theoretical investigations were carried out by means of numerical simulations based on a 2D and 3D finite differences method. By modelling and experimental investigations it was demonstrated that presence of any type of the defect disturbs the leaky wave and enables to detect them. So, the spatial position of defects can be determined also. It was shown that such important defects as a disbond of the plies essentially reduce or even completely suppress the leaky wave, so they can be detected quit easily.

  19. 49 CFR 236.508 - Interference with application of brakes by means of brake valve.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Interference with application of brakes by means of brake valve. 236.508 Section 236.508 Transportation Other Regulations Relating to Transportation... Interference with application of brakes by means of brake valve. The automatic train stop, train control,...

  20. 49 CFR 236.508 - Interference with application of brakes by means of brake valve.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Interference with application of brakes by means of brake valve. 236.508 Section 236.508 Transportation Other Regulations Relating to Transportation... Interference with application of brakes by means of brake valve. The automatic train stop, train control,...

  1. 49 CFR 236.508 - Interference with application of brakes by means of brake valve.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Interference with application of brakes by means of brake valve. 236.508 Section 236.508 Transportation Other Regulations Relating to Transportation... Interference with application of brakes by means of brake valve. The automatic train stop, train control,...

  2. 49 CFR 236.508 - Interference with application of brakes by means of brake valve.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Interference with application of brakes by means of brake valve. 236.508 Section 236.508 Transportation Other Regulations Relating to Transportation... Interference with application of brakes by means of brake valve. The automatic train stop, train control,...

  3. 49 CFR 236.508 - Interference with application of brakes by means of brake valve.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Interference with application of brakes by means of brake valve. 236.508 Section 236.508 Transportation Other Regulations Relating to Transportation... Interference with application of brakes by means of brake valve. The automatic train stop, train control,...

  4. 14 CFR 27.735 - Brakes.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... STANDARDS: NORMAL CATEGORY ROTORCRAFT Design and Construction Landing Gear § 27.735 Brakes. For rotorcraft with wheel-type landing gear, a braking device must be installed that is— (a) Controllable by the...

  5. 14 CFR 29.735 - Brakes.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction Landing Gear § 29.735 Brakes. For rotorcraft with wheel-type landing gear, a braking device must be installed that is— (a) Controllable by...

  6. 14 CFR 29.735 - Brakes.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction Landing Gear § 29.735 Brakes. For rotorcraft with wheel-type landing gear, a braking device must be installed that is— (a) Controllable by...

  7. 14 CFR 27.735 - Brakes.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... STANDARDS: NORMAL CATEGORY ROTORCRAFT Design and Construction Landing Gear § 27.735 Brakes. For rotorcraft with wheel-type landing gear, a braking device must be installed that is— (a) Controllable by the...

  8. Four-wheel dual braking for automobiles

    NASA Technical Reports Server (NTRS)

    Edwards, H. B.

    1981-01-01

    Each master cylinder applies braking power to all four wheels unlike conventional systems where cylinder operates only two wheels. If one master system fails because of fluid loss, other stops car by braking all four wheels although at half force.

  9. A Demonstration of Car Braking Instabilities.

    ERIC Educational Resources Information Center

    Irwin, Jack; Swinson, Derek

    1990-01-01

    Detailed are the construction of a demonstration car, apparatus and procedures used in the demonstration, and the analysis of the effects of car braking. The cases of rear-wheel and front-wheel braking are considered. (CW)

  10. Planes, Politics and Oral Proficiency: Testing International Air Traffic Controllers

    ERIC Educational Resources Information Center

    Moder, Carol Lynn; Halleck, Gene B.

    2009-01-01

    This study investigates the variation in oral proficiency demonstrated by 14 Air Traffic Controllers across two types of testing tasks: work-related radio telephony-based tasks and non-specific English tasks on aviation topics. Their performance was compared statistically in terms of level ratings on the International Civil Aviation Organization…

  11. FIELD TEST OF AIR SPARGING COUPLED WITH SOIL VAPOR EXTRACTION

    EPA Science Inventory

    A controlled field study was designed and conducted to assess the performance of air sparging for remediation of petroleum fuel and solvent contamination in a shallow (3-m deep) groundwater aquifer. Sparging was performed in an insolation test cell (5 m by 3 m by 8-m deep). A soi...

  12. Test results of flight guidance for fuel conservative descents in a time-based metered air traffic environment. [terminal configured vehicle

    NASA Technical Reports Server (NTRS)

    Knox, C. E.; Person, L. H., Jr.

    1981-01-01

    The NASA developed, implemented, and flight tested a flight management algorithm designed to improve the accuracy of delivering an airplane in a fuel-conservative manner to a metering fix at a time designated by air traffic control. This algorithm provides a 3D path with time control (4D) for the TCV B-737 airplane to make an idle-thrust, clean configured (landing gear up, flaps zero, and speed brakes retracted) descent to arrive at the metering fix at a predetermined time, altitude, and airspeed. The descent path is calculated for a constant Mach/airspeed schedule from linear approximations of airplane performance with considerations given for gross weight, wind, and nonstandard pressure and temperature effects. The flight management descent algorithms are described and flight test results are presented.

  13. Modeling Airborne Beryllium Concentrations From Open Air Dynamic Testing

    NASA Astrophysics Data System (ADS)

    Becker, N. M.

    2003-12-01

    A heightened awareness of airborne beryllium contamination from industrial activities was reestablished during the late 1980's and early 1990's when it became recognized that Chronic Beryllium Disease (CBD) had not been eradicated, and that the Occupational Health and Safety Administration standards for occupational air exposure to beryllium may not be sufficiently protective. This was in response to the observed CBD increase in multiple industrial settings where beryllium was manufactured and/or machined, thus producing beryllium particulates which are then available for redistribution by airborne transport. Sampling and modeling design activities were expanded at Los Alamos National Laboratory in New Mexico to evaluate potential airborne beryllium exposure to workers who might be exposed during dynamic testing activities associated with nuclear weapons Stockpile Stewardship. Herein is presented the results of multiple types of collected air measurements that were designed to characterize the production and dispersion of beryllium used in components whose performance is evaluated during high explosive detonation at open air firing sites. Data from fallout, high volume air, medium volume air, adhesive film, particle size impactor, and fine-particulate counting techniques will be presented, integrated, and applied in dispersion modeling to assess potential onsite and offsite personal exposures resulting from dynamic testing activities involving beryllium.

  14. 49 CFR 238.231 - Brake system.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Brake system. 238.231 Section 238.231... Equipment § 238.231 Brake system. Except as otherwise provided in this section, on or after September 9... train's primary brake system shall be capable of stopping the train with a service application from...

  15. 49 CFR 238.431 - Brake system.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... train from its maximum operating speed within the signal spacing existing on the track over which the... to initiate an emergency brake application need only be provided at one location in the unit. (d) The... speed for safe operation of the train using only the friction brake portion of the blended brake with...

  16. 49 CFR 229.53 - Brake gauges.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Brake gauges. 229.53 Section 229.53 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION RAILROAD LOCOMOTIVE SAFETY STANDARDS Safety Requirements Brake System § 229.53 Brake gauges....

  17. 30 CFR 56.14101 - Brakes.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Brakes. 56.14101 Section 56.14101 Mineral... Devices and Maintenance Requirements § 56.14101 Brakes. (a) Minimum requirements. (1) Self-propelled mobile equipment shall be equipped with a service brake system capable of stopping and holding...

  18. 30 CFR 57.14101 - Brakes.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Brakes. 57.14101 Section 57.14101 Mineral... Devices and Maintenance Requirements § 57.14101 Brakes. (a) Minimum requirements. (1) Self-propelled mobile equipment shall be equipped with a service brake system capable of stopping and holding...

  19. 30 CFR 36.29 - Brakes.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Brakes. 36.29 Section 36.29 Mineral Resources... and Design Requirements § 36.29 Brakes. All mobile diesel-powered transportation equipment shall be equipped with adequate brakes acceptable to MSHA....

  20. Friction brake cushions acceleration and vibration loads

    NASA Technical Reports Server (NTRS)

    Fraser, G. F.; Zawadski, G. Z.

    1966-01-01

    Friction brake cushions an object in a vehicle from axially applied vibration and steady-state acceleration forces. The brake incorporates a doubly tapered piston that applies a controlled radial force to friction brake segments bearing against the walls of a cylinder.

  1. 49 CFR 229.46 - Brakes: general.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Brakes: general. 229.46 Section 229.46 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION RAILROAD LOCOMOTIVE SAFETY STANDARDS Safety Requirements Brake System § 229.46 Brakes: general. (a) Before each trip,...

  2. 49 CFR 229.46 - Brakes: General.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Brakes: General. 229.46 Section 229.46 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION RAILROAD LOCOMOTIVE SAFETY STANDARDS Safety Requirements Brake System § 229.46 Brakes: General. The carrier shall know...

  3. Compact, Lightweight Servo-Controllable Brakes

    NASA Technical Reports Server (NTRS)

    Lovchik, Christopher S.; Townsend, William; Guertin, Jeffrey; Matsuoka, Yoky

    2010-01-01

    Compact, lightweight servo-controllable brakes capable of high torques are being developed for incorporation into robot joints. A brake of this type is based partly on the capstan effect of tension elements. In a brake of the type under development, a controllable intermediate state of torque is reached through on/off switching at a high frequency.

  4. 49 CFR 229.53 - Brake gauges.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Brake gauges. 229.53 Section 229.53 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION RAILROAD LOCOMOTIVE SAFETY STANDARDS Safety Requirements Brake System § 229.53 Brake gauges....

  5. 30 CFR 36.29 - Brakes.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Brakes. 36.29 Section 36.29 Mineral Resources... and Design Requirements § 36.29 Brakes. All mobile diesel-powered transportation equipment shall be equipped with adequate brakes acceptable to MSHA....

  6. 30 CFR 36.29 - Brakes.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Brakes. 36.29 Section 36.29 Mineral Resources... and Design Requirements § 36.29 Brakes. All mobile diesel-powered transportation equipment shall be equipped with adequate brakes acceptable to MSHA....

  7. 30 CFR 36.29 - Brakes.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Brakes. 36.29 Section 36.29 Mineral Resources... and Design Requirements § 36.29 Brakes. All mobile diesel-powered transportation equipment shall be equipped with adequate brakes acceptable to MSHA....

  8. 30 CFR 36.29 - Brakes.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Brakes. 36.29 Section 36.29 Mineral Resources... and Design Requirements § 36.29 Brakes. All mobile diesel-powered transportation equipment shall be equipped with adequate brakes acceptable to MSHA....

  9. 49 CFR 229.53 - Brake gauges.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Brake gauges. 229.53 Section 229.53 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION RAILROAD LOCOMOTIVE SAFETY STANDARDS Safety Requirements Brake System § 229.53 Brake gauges....

  10. 49 CFR 229.53 - Brake gauges.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Brake gauges. 229.53 Section 229.53 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION RAILROAD LOCOMOTIVE SAFETY STANDARDS Safety Requirements Brake System § 229.53 Brake gauges....

  11. 49 CFR 229.53 - Brake gauges.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Brake gauges. 229.53 Section 229.53 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION RAILROAD LOCOMOTIVE SAFETY STANDARDS Safety Requirements Brake System § 229.53 Brake gauges....

  12. 49 CFR 229.46 - Brakes: general.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Brakes: general. 229.46 Section 229.46..., DEPARTMENT OF TRANSPORTATION RAILROAD LOCOMOTIVE SAFETY STANDARDS Safety Requirements Brake System § 229.46 Brakes: general. (a) Before each trip, the railroad shall know the following: (1) The locomotive...

  13. Test Report for Perforated Metal Air Transportable Package (PMATO) Prototype.

    SciTech Connect

    Bobbe, Jeffery G.; Pierce, Jim Dwight

    2003-06-01

    A prototype design for a plutonium air transport package capable of carrying 7.6 kg of plutonium oxide and surviving a ''worst-case'' plane crash has been developed by Sandia National Laboratories (SNL) for the Japan Nuclear Cycle Development Institute (JNC). A series of impact tests were conducted on half-scale models of this design for side, end, and comer orientations at speeds close to 282 m/s onto a target designed to simulate weathered sandstone. These tests were designed to evaluate the performance of the overpack concept and impact-limiting materials in critical impact orientations. The impact tests of the Perforated Metal Air Transportable Package (PMATP) prototypes were performed at SNL's 10,000-ft rocket sled track. This report describes test facilities calibration and environmental testing methods of the PMATP under specific test conditions. The tests were conducted according to the test plan and procedures that were written by the authors and approved by SNL management and quality assurance personnel. The result of these tests was that the half-scale PMATP survived the ''worst-case'' airplane crash conditions, and indicated that a full-scale PMATP, utilizing this overpack concept and these impact-limiting materials, would also survive these crash conditions.

  14. Testing of a refuelable zinc/air bus battery

    SciTech Connect

    Cooper, J.F.; Fleming, D.; Koopman, R.; Hargrove, D.; Maimoni, A.; Peterman, K.

    1995-02-22

    We report tests of a refuelable zinc/air battery of modular, bipolar-cell design, intended for fleet electric busses and vans. The stack consists of twelve 250-cm{sup 2} cells built of two units: (1) a copper-clad glass-reinforced epoxy board supporting anode and cathode current collectors, and (2) polymer frame providing for air- and electrolyte distribution and zinc fuel storage. The stack was refueled in 4 min. by a hydraulic transfer of zinc particles entrained in solution flow.

  15. Prosthetic leg powered by MR brake and SMA wires

    NASA Astrophysics Data System (ADS)

    Nguyen, The; Munguia, Vicente; Calderon, Jose

    2014-04-01

    Current knee designs for prosthetic legs rely on electric motors for both moving and stationary states. The electric motors draw an especially high level of current to sustain a fixed position. The advantage of using magnetorheological (MR) fluid is that it requires less current and can have a variable braking torque. Besides, the proposed prosthetic leg is actuated by NiTinol wire, a popular shape memory alloy (SMA). The incorporation of NiTinol gives the leg more realistic weight distribution with appropriate arrangement of the batteries and wires. The prosthesis in this research was designed with MR brake as stopping component and SMA wire network as actuating component at the knee. The MR brake was designed with novel non-circular shape for the rotor that improved the braking torque while minimizing the power consumption. The design also helped simplify the control of braking process. The SMA wire network was design so that the knee motion was actively rotated in both directions. The SMA wires were arranged and played very similar role as the leg's muscles. The study started with the overall solid design of the knee including both MR and SMA parts. Theoretical models were derived and programmed in Simulink for both components. The simulation was capable of predicting the power required for moving the leg or hold it in a fixed position for a certain amount of time. Subsequently, the design was prototyped and tested to validate the theoretical prediction. The theoretical models were updated accordingly to correlate with the experimental data.

  16. Frictional behavior of automotive brake materials under wet and dry conditions

    SciTech Connect

    Blau, P.J.; Martin, R.L.; Weintraub, M.H.; Jang, Ho; Donlon, W.

    1996-12-15

    The purpose of this effort was to develop an improved understanding of the relationship between the structure and frictional behavior of materials in the disc brake/rotor interface with a view toward improving the performance of automotive disc brakes. The three tasks involved in this Cooperative Research and Development Agreement (CRADA) were as follows: Task 1. Investigation of Brake Pads and Rotors. Characterize surface features of worn brake pads and rotors, with special attention to the transfer film which forms on them during operation. Ford to supply specimens for examination and other supporting information. Task 2. Effects of Atmosphere and Repeated Applications on Brake Material Friction. Conduct pin-on-disk friction tests at ORNL under controlled moisture levels to determine effects of relative humidity on frictional behavior of brake pad and rotor materials. Conduct limited tests on the characteristics of friction under application of repeated contacts. Task 3. Comparison of Dynamometer Tests with Laboratory Friction Tests. Compare ORNL friction data with Ford dynamometer test data to establish the degree to which the simple bench tests can be useful in helping to understand frictional behavior in full-scale brake component tests. This final report summarizes work performed under this CRADA.

  17. Experimental study using infrared thermography on the convective heat transfer of a TGV brake disc in the actual environment

    NASA Astrophysics Data System (ADS)

    Siroux, Monica; Harmand, Souad; Desmet, Bernard

    2002-07-01

    We present an experimental identification of the local and mean Nusselt number from a rotating TGV brake disk model in the actual environment and exposed to an air flow parallel to the disk surface. This method is based on the use of a heated thermally thick disk combined with the technique of temperature measurement by infrared thermography. The local and mean convective heat transfer coefficient from the disk surface is identified by solving the steady state heat equation by a finite difference method using the experimental temperature distribution as boundary conditions. The experimental setup is constituted of a model disk with all the representative parts of the actual TGV brake system. The disk and its actual environment are inside a wind tunnel test section, so that the rotational disk speed and the air flow velocity can be varied. Tests were carried out for rotational speeds w between 325 and 2000 rpm (rotational Reynolds number Re between 88,500 and 545,000), and for an air flow velocity U ranging between 0 and 12 m(DOT)s-1 (air flow Reynolds number Re0 between 0 and 153,000).

  18. Thermal measurement of brake pad lining surfaces during the braking process

    NASA Astrophysics Data System (ADS)

    Piątkowski, Tadeusz; Polakowski, Henryk; Kastek, Mariusz; Baranowski, Pawel; Damaziak, Krzysztof; Małachowski, Jerzy; Mazurkiewicz, Łukasz

    2012-06-01

    This paper presents the test campaign concept and definition and the analysis of the recorded measurements. One of the most important systems in cars and trucks are brakes. The braking temperature on a lining surface can rise above 500°C. This shows how linings requirements are so strict and, what is more, continuously rising. Besides experimental tests, very supportive method for investigating processes which occur on the brake pad linings are numerical analyses. Experimental tests were conducted on the test machine called IL-68. The main component of IL-68 is so called frictional unit, which consists of: rotational head, which convey a shaft torque and where counter samples are placed and translational head, where samples of coatings are placed and pressed against counter samples. Due to the high rotational speeds and thus the rapid changes in temperature field, the infrared camera was used for testing. The paper presents results of analysis registered thermograms during the tests with different conditions. Furthermore, based on this testing machine, the numerical model was developed. In order to avoid resource demanding analyses only the frictional unit (described above) was taken into consideration. Firstly the geometrical model was performed thanks to CAD techniques, which in the next stage was a base for developing the finite element model. Material properties and boundary conditions exactly correspond to experimental tests. Computations were performed using a dynamic LS-Dyna code where heat generation was estimated assuming full (100%) conversion of mechanical work done by friction forces. Paper presents the results of dynamic thermomechanical analysis too and these results were compared with laboratory tests.

  19. Aluminum runway surface as possible aid to aircraft braking

    NASA Technical Reports Server (NTRS)

    Miller, C. D.; Pinkel, I. I.

    1973-01-01

    Several concepts are described for use singly or in combination to improve aircraft braking. All involve a thin layer of aluminum covering all or part of the runway. Advantage would derive from faster heat conduction from the tire-runway interface. Heating of tread surface with consequent softening and loss of friction coefficient should be reduced. Equations are developed indicating that at least 99 percent of friction heat should flow into the aluminum. Preliminary test results indicate a coefficient of sliding friction of 1.4, with predictably slight heating of tread. Elimination of conventional brakes is at least a remote possibility.

  20. Analysis of heat conduction in a drum brake system of the wheeled armored personnel carriers

    NASA Astrophysics Data System (ADS)

    Puncioiu, A. M.; Truta, M.; Vedinas, I.; Marinescu, M.; Vinturis, V.

    2015-11-01

    This paper is an integrated study performed over the Braking System of the Wheeled Armored Personnel Carriers. It mainly aims to analyze the heat transfer process which is present in almost any industrial and natural process. The vehicle drum brake systems can generate extremely high temperatures under high but short duration braking loads or under relatively light but continuous braking. For the proper conduct of the special vehicles mission in rough terrain, we are talking about, on one hand, the importance of the possibility of immobilization and retaining position and, on the other hand, during the braking process, the importance movement stability and reversibility or reversibility, to an encounter with an obstacle. Heat transfer processes influence the performance of the braking system. In the braking phase, kinetic energy transforms into thermal energy resulting in intense heating and high temperature states of analyzed vehicle wheels. In the present work a finite element model for the temperature distribution in a brake drum is developed, by employing commercial finite element software, ANSYS. These structural and thermal FEA models will simulate entire braking event. The heat generated during braking causes distortion which modifies thermoelastic contact pressure distribution drum-shoe interface. In order to capture the effect of heat, a transient thermal analysis is performed in order to predict the temperature distribution transitional brake components. Drum brakes are checked both mechanical and thermal. These tests aim to establish their sustainability in terms of wear and the variation coefficient of friction between the friction surfaces with increasing temperature. Modeling using simulation programs led eventually to the establishment of actual thermal load of the mechanism of brake components. It was drawn the efficiency characteristic by plotting the coefficient of effectiveness relative to the coefficient of friction shoe-drum. Thus induced

  1. Bidirectional drive and brake mechanism

    NASA Technical Reports Server (NTRS)

    Swan, Scott A. (Inventor)

    1991-01-01

    A space transport vehicle is disclosed as including a body which is arranged to be movably mounted on an elongated guide member disposed in outer space and driven therealong. A drive wheel is mounted on a drive shaft and arranged to be positioned in rolling engagement with the elongated guide carrying the vehicle. A brake member is arranged on the drive shaft for movement into and out of engagement with an adjacent surface of the drive wheel. An actuator is mounted on the body to be manually moved back and forth between spaced positions in an arc of movement. A ratchet-and-pawl mechanism is arranged to operate upon movements of the actuator in one direction between first and second positions for coupling the actuator to the drive wheel to incrementally rotate the wheel in one rotational direction and to operate upon movements of the actuator in the opposite direction for uncoupling the actuator from the wheel. The brake member is threadedly coupled to the drive shaft in order that the brake member will be operated only when the actuator is moved on beyond its first and second positions for shifting the brake member along the drive shaft and into frictional engagement with the adjacent surface on the drive wheel.

  2. Brake blending strategy for a hybrid vehicle

    DOEpatents

    Boberg, Evan S.

    2000-12-05

    A hybrid electric powertrain system is provided including a transmission for driving a pair of wheels of a vehicle and a heat engine and an electric motor/generator coupled to the transmission. A friction brake system is provided for applying a braking torque to said vehicle. A controller unit generates control signals to the electric motor/generator and the friction brake system for controllably braking the vehicle in response to a drivers brake command. The controller unit determines and amount of regenerative torque available and compares this value to a determined amount of brake torque requested for determining the control signals to the electric motor/generator and the friction brake system.

  3. Effect of Road Adhesion Coefficient on Tractor-Semitrailer Cornering Braking Stability

    NASA Astrophysics Data System (ADS)

    Wang, Wei; Li, Chen; Tang, Geteng; Wang, Cheng

    A dynamic model of tractor-semitrailer cornering braking was established in this paper, and the accuracy of the model was verified by real vehicle test. By model simulation of the cornering braking process, different road adhesion coefficient such as 0.15, 0.3, 0.45, 0.6, 0.75 was chosen to analyzed the changing curve of braking distance, articulation angle, yaw rate and lateral acceleration when initial speed of tractor-semitrailer was 30km h. The result showed that the peak values of articulation angle, yaw rate and lateral acceleration gotten by simulation were the largest. On the road of road adhesion coefficient 0.15, distance of tractor-semitrailer cornering braking was the longest. On the road of road adhesion coefficient 0.75, distance of tractor-semitrailer cornering braking was the shortest and the peak values of articulation angle, yaw rate and lateral acceleration were small relatively.

  4. Some effects of grooved runway configurations on aircraft tire braking traction under flooded runway conditions

    NASA Technical Reports Server (NTRS)

    Byrdsong, T. A.

    1973-01-01

    An experimental investigation was conducted to study the effect of grooved runway configurations on aircraft tire braking traction on flooded runway surfaces. The investigation was performed, utilizing size 49 x 17, type VII, aircraft tires with an inflation pressure of 170 lb per square inch at ground speeds up to approximately 120 knots. The results of this investigation indicate that when the runway is flooded, grooved surfaces provide better braking traction than an ungrooved surface and, in general, the level of braking traction was found to improve as the tire bearing pressure was increased because of an increase in the groove area of either the surface or the tire tread. Rounding the groove edges tended to degrade the tire braking capability from that developed on the same groove configuration with sharp edges. Results also indicate that braking friction coefficients for the test tires and runway surfaces decreased as ground speed was increased because of the hydroplaning effects.

  5. F-1 Engine Test Firing at Edwards Air Force Base

    NASA Technical Reports Server (NTRS)

    1962-01-01

    This photograph depicts the Rocketdyne static firing of the F-1 engine at the towering 76-meter Test Stand 1-C in Area 1-125 of the Edwards Air Force Base in California. The Saturn V S-IC (first) stage utilized five F-1 engines for its thrust. Each engine provided 1,500,000 pounds, for a combined thrust of 7,500,000 pounds with liquid oxygen and kerosene as its propellants.

  6. Cycling and wind: does sidewind brake?

    NASA Astrophysics Data System (ADS)

    Íñiguez-de-la-Torre, I.; Íñiguez, J.

    2006-01-01

    It is well established that the presence of wind is crucial for the practice of numerous outdoor sports. Among them, the case of cycling competition is especially important because the speeds that are developed are perfectly comparable with moderate or strong winds, giving rise to great variability in race times. Conversely, the sidewind seems to behave as neutral in the race, and nevertheless all the cyclists know the difficulties that it causes. In this brief paper we show that the sidewind also produces an appreciable braking as a consequence of the quadratic dependence of the aerodynamic drag force on the air speed. Our work presents an interesting problem of mechanics and physics of fluids, which may be suitable as a task for intermediate level students in university courses.

  7. Control room envelope unfiltered air inleakage test protocols

    SciTech Connect

    Lagus, P.L.; Grot, R.A.

    1997-08-01

    In 1983, the Advisory Committee on Reactor Safeguards (ACRS) recommended that the US NRC develop a control room HVAC performance testing protocol. To date no such protocol has been forthcoming. Beginning in mid-1994, an effort was funded by NRC under a Small Business Innovation Research (SBIR) grant to develop several simplified test protocols based on the principles of tracer gas testing in order to measure the total unfiltered inleakage entering a CRE during emergency mode operation of the control room ventilation system. These would allow accurate assessment of unfiltered air inleakage as required in SRP 6.4. The continuing lack of a standard protocol is unfortunate since one of the significant parameters required to calculate operator dose is the amount of unfiltered air inleakage into the control room. Often it is assumed that, if the Control Room Envelope (CRE) is maintained at +1/8 in. w.g. differential pressure relative to the surroundings, no significant unfiltered inleakage can occur it is further assumed that inleakage due to door openings is the only source of unfiltered air. 23 refs., 13 figs., 2 tabs.

  8. Investigation on hardness and impact resistance of automotive brake pad composed with rice husk dust

    NASA Astrophysics Data System (ADS)

    Bahari, Shahril Anuar; Isa, Khairul Hafizee; Kassim, Masitah Abu; Mohamed, Zulkifli; Othman, Eliasidi Abu

    2012-06-01

    In this study, hardness and impact resistance properties of automotive brake pad composed with rice husk dust (RHD) were documented. RHD was mixed with other metallic and synthetic ingredients of automotive brake pad. To obtain RHD, rice husk was ground and dried to 1 - 3% moisture content. The RHD was screened to obtain different dust sizes (80 and 100-mesh) before it was mixed with other materials at different percentages of composition (10 and 30%). The mixture was then pressed to produce brake pad. Rockwell hardness testing machine was used in hardness determination, while Izod impact testing machine was used in impact resistance determination. Hardness resistance of automotive brake pad mixed with 10% composition and 80-mesh size of RHD was significantly higher than 100-mesh. Hardness resistance of automotive brake pad mixed with 30% composition and 100-mesh size of RHD was slightly higher than 80 mesh. However, based on analysis, the difference was not significant. According to the result, hardness resistance of automotive brake pad mixed with 30% composition of RHD was higher than 10%. RHD has filled up the space and enhanced the micro structural behaviour of automotive brake pad. Impact resistance of automotive brake pad mixed with 10% composition and 80-mesh size of RHD was insignificantly higher than 100-mesh. Impact resistance of automotive brake pad mixed with 30% composition and 80-mesh size of RHD was significantly higher than 100 mesh. Large RHD size has increased the capability to resist high-rated impact loading. The impact energy was distributed over wider area for larger particle size. This factor has increased the impact resistance of automotive brake pad from large dust size. Impact resistance of automotive brake pad mixed with 80-mesh size and 30% composition of RHD was higher than 10%. In contrast, impact resistance of automotive brake pad mixed with 100-mesh size and 10% composition of RHD was higher than 30%. However, the difference was not

  9. Development of a Test Facility for Air Revitalization Technology Evaluation

    NASA Technical Reports Server (NTRS)

    Lu, Sao-Dung; Lin, Amy; Campbell, Melissa; Smith, Frederick; Curley, Su

    2007-01-01

    Development of new air revitalization system (ARS) technology can initially be performed in a subscale laboratory environment, but in order to advance the maturity level, the technology must be tested in an end-to-end integrated environment. The Air Revitalization Technology Evaluation Facility (ARTEF) at the NASA Johnson Space Center serves as a ground test bed for evaluating emerging ARS technologies in an environment representative of spacecraft atmospheres. At the center of the ARTEF is a hypobaric chamber which serves as a sealed atmospheric chamber for closed loop testing. A Human Metabolic Simulator (HMS) was custom-built to simulate the consumption of oxygen, and production of carbon dioxide, moisture and heat of up to eight persons. A multitude of gas analyzers and dew point sensors are used to monitor the chamber atmosphere upstream and downstream of a test article. A robust vacuum system is needed to simulate the vacuum of space. A reliable data acquisition and control system is required to connect all the subsystems together. This paper presents the capabilities of the integrated test facility and some of the issues encountered during the integration.

  10. STANDARDS CONTROLLING AIR EMISSIONS FOR THE SOIL DESICCATION PILOT TEST

    SciTech Connect

    BENECKE MW

    2010-09-08

    This air emissions document supports implementation of the Treatability Test Plan for Soil Desiccation as outlined in the Deep Vadose Zone Treatability Test Plan for the Hanford Central Plateau (DOE/RL-2007-56). Treatability testing supports evaluation of remedial technologies for technetium-99 (Tc-99) contamination in the vadose zone at sites such as the BC Cribs and Trenches. Soil desiccation has been selected as the first technology for testing because it has been recommended as a promising technology in previous Hanford Site technology evaluations and because testing of soil desiccation will provide useful information to enhance evaluation of other technologies, in particular gas-phase remediation technologies. A soil desiccation pilot test (SDPT) will evaluate the desiccation process (e.g., how the targeted interval is dried) and the long-term performance for mitigation of contaminant transport. The SDPT will dry out a moist zone contaminated by Tc-99 and nitrate that has been detected at Well 299-E13-62 (Borehole C5923). This air emissions document applies to the activities to be completed to conduct the SDPT in the 200-BC-1 operable unit located in the 200 East Area of the Hanford Site. Well 299-E13-62 is planned to be used as an injection well. This well is located between and approximately equidistant from cribs 216-B-16, 216-B-17, 216-B-18. and 216-B-19. Nitrogen gas will be pumped at approximately 300 ft{sup 3}/min into the 299-EI3-62 injection well, located approximately 12 m (39 ft) away from extraction well 299-EI3-65. The soil gas extraction rate will be approximately 150 ft{sup 3}/min. The SDPT will be conducted continuously over a period of approximately six months. The purpose of the test is to evaluate soil desiccation as a potential remedy for protecting groundwater. A conceptual depiction is provided in Figure 1. The soil desiccation process will physically dry, or evaporate, some of the water from the moist zone of interest. As such, it is

  11. Core testing of zinc/air refuelable battery modules

    SciTech Connect

    Cooper, J. F., LLNL

    1998-08-20

    We are developing a refuelable zinc/air battery (6-cells) for evaluation under the five USABC `core` test protocols. In the first half of the two year project ($1OOK, FY1997), an advanced refuelable design was developed, fabricated and tested at power levels up to 415 W. Performance matched or exceeded that of earlier multicell systems. A computer program was developed for automated data acquisition and drive cycle simulation. Small mockup cells (80 cm 2) were constructed for rapid testing of components. In the follow-on effort (FY1998, $1OOK) we will make minor advances in system design and fabrication efficiency, and seek to improve cathode performance and life, before delivery of two final units for test at DOE laboratory.

  12. Hazardous air pollutant testing at the LGTI coal gasification plant

    SciTech Connect

    Wetherold, R.G.; Williams, W.A.; Maxwell, D.P.; Mann, R.M.

    1995-06-01

    A comprehensive hazardous air pollutant test program was conducted in November 1994 at the Louisiana Gasification Technology, Inc. (LGTI), plant in Plaquemine, Louisiana. This program was sponsored by DOE/PETC, the Electric Power Research Institute (EPRI), and Destec Energy. In May of 1995, additional testing of the hot syngas stream was conducted at the LGTI facility under this same program. DOE/METC provided additional technical support for the hot gas testing effort. In this paper, the sampling and analytical methods used during the November and May test program are summarized. The hot gas testing is described in greater detail. In particular, the hot gas sampling probe and probe insertion/withdrawal system are discussed. The sampling probe was designed to collect particulate and extract gas samples at process temperature and pressure. The design of the probe system is described, and the operating procedures are summarized. The operation of the probe during the testing is discussed, and photographs of the testing are provided. In addition to the summaries and descriptions of the test methodologies, selected preliminary emissions results of the November sampling are included in the paper.

  13. 49 CFR 236.701 - Application, brake; full service.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Application, brake; full service. 236.701 Section... § 236.701 Application, brake; full service. An application of the brakes resulting from a continuous or a split reduction in brake pipe pressure at a service rate until maximum brake cylinder pressure...

  14. 49 CFR 230.77 - Foundation brake gear.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Foundation brake gear. 230.77 Section 230.77... Tenders Brake and Signal Equipment § 230.77 Foundation brake gear. (a) Maintenance. Foundation brake gear...) Distance above the rails. No part of the foundation brake gear of the steam locomotive or tender shall...

  15. 49 CFR 230.77 - Foundation brake gear.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Foundation brake gear. 230.77 Section 230.77... Tenders Brake and Signal Equipment § 230.77 Foundation brake gear. (a) Maintenance. Foundation brake gear...) Distance above the rails. No part of the foundation brake gear of the steam locomotive or tender shall...

  16. 49 CFR 230.77 - Foundation brake gear.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Foundation brake gear. 230.77 Section 230.77... Tenders Brake and Signal Equipment § 230.77 Foundation brake gear. (a) Maintenance. Foundation brake gear...) Distance above the rails. No part of the foundation brake gear of the steam locomotive or tender shall...

  17. 49 CFR 230.77 - Foundation brake gear.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Foundation brake gear. 230.77 Section 230.77... Tenders Brake and Signal Equipment § 230.77 Foundation brake gear. (a) Maintenance. Foundation brake gear...) Distance above the rails. No part of the foundation brake gear of the steam locomotive or tender shall...

  18. 49 CFR 570.55 - Hydraulic brake system.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 6 2010-10-01 2010-10-01 false Hydraulic brake system. 570.55 Section 570.55... 10,000 Pounds § 570.55 Hydraulic brake system. The following requirements apply to vehicles with hydraulic brake systems. (a) Brake system failure indicator. The hydraulic brake system failure...

  19. 49 CFR 236.701 - Application, brake; full service.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Application, brake; full service. 236.701 Section... § 236.701 Application, brake; full service. An application of the brakes resulting from a continuous or a split reduction in brake pipe pressure at a service rate until maximum brake cylinder pressure...

  20. 49 CFR 393.49 - Control valves for brakes.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 5 2014-10-01 2014-10-01 false Control valves for brakes. 393.49 Section 393.49... NECESSARY FOR SAFE OPERATION Brakes § 393.49 Control valves for brakes. (a) General rule. Except as provided..., which is equipped with power brakes, must have the braking system so arranged that one application...

  1. 49 CFR 236.701 - Application, brake; full service.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Application, brake; full service. 236.701 Section... § 236.701 Application, brake; full service. An application of the brakes resulting from a continuous or a split reduction in brake pipe pressure at a service rate until maximum brake cylinder pressure...

  2. 49 CFR 236.701 - Application, brake; full service.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Application, brake; full service. 236.701 Section... § 236.701 Application, brake; full service. An application of the brakes resulting from a continuous or a split reduction in brake pipe pressure at a service rate until maximum brake cylinder pressure...

  3. 49 CFR 393.49 - Control valves for brakes.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 5 2012-10-01 2012-10-01 false Control valves for brakes. 393.49 Section 393.49... NECESSARY FOR SAFE OPERATION Brakes § 393.49 Control valves for brakes. (a) General rule. Except as provided..., which is equipped with power brakes, must have the braking system so arranged that one application...

  4. 49 CFR 393.49 - Control valves for brakes.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 5 2013-10-01 2013-10-01 false Control valves for brakes. 393.49 Section 393.49... NECESSARY FOR SAFE OPERATION Brakes § 393.49 Control valves for brakes. (a) General rule. Except as provided..., which is equipped with power brakes, must have the braking system so arranged that one application...

  5. Analysis of the stability of PTW riders in autonomous braking scenarios.

    PubMed

    Symeonidis, Ioannis; Kavadarli, Gueven; Erich, Schuller; Graw, Matthias; Peldschus, Steffen

    2012-11-01

    While fatalities of car occupants in the EU decreased remarkably over the last decade, Powered Two Wheelers (PTWs) fatalities still increase following the increase of PTW ownership. Autonomous braking systems have been implemented in several types of vehicles and are presently addressed by research in the field of PTWs. A major concern in this context is the rider stability. Experiments with volunteers were performed in order to find out whether autonomous braking for PTWs will produce a greater instability of the rider in comparison to manual braking. The PTW's braking conditions were simulated in a laboratory with a motorcycle mock-up mounted on a sled, which was accelerated with an average of 0.35 g. The motion of the rider was captured in autonomous braking scenarios with and without pre-warning as well as in manual braking scenarios. No significant differences between the scenarios were found with respect to maximum forward displacement of the volunteer's torso and head (p<0.05). By performing clustering analysis on two kinematic parameters, two different strategies of the volunteers were identified. They were not related to the braking scenarios. A relation of the clusters with the initial posture represented by the elbow angle was revealed (p<0.05). It is concluded that autonomous braking at low deceleration will not cause significant instabilities of the rider in comparison to manual braking in idealized laboratory conditions. Based on this, further research into the development and implementation of autonomous braking systems for PTWs, e.g. by extensive riding tests, seems valuable. PMID:23036398

  6. Characterization of the high-frequency squeal on a laboratory brake setup

    NASA Astrophysics Data System (ADS)

    Giannini, Oliviero; Massi, Francesco

    2008-02-01

    This paper presents an experimental investigation on high-frequency brake squeal noise conducted on an appropriately designed experimental rig, called laboratory brake. Brake squeal is one of the major issues in the design process of an automotive brake and the development of a robust procedure for a "squeal-free" design is still under investigation. The high-frequency squeal is the most frequent noise generated by automotive brakes and is characterized by a wavelength of the "squealing mode" comparable to the length of the brake pad. The proposed "laboratory brake" is a good compromise between simple test rigs, such as the beam-on-disc, and the experimental setups that use real brakes. The beam-on-disc setup is a useful tool to understand the mechanism leading to the instability, but it does not simulate appropriately a real brake. On the other hand, real brakes are too complex for fundamental investigation and for efficient modeling. The experimental analysis shows a strong correlation between the length of the pad, the dynamic behavior of the system, and the squealing deformed shape. Moreover, depending on the length of the pad compared with the wavelength of the disc mode, three different kind of squeal instability may occur during experiments: the sine mode squeal, the cosine mode squeal and the rotating squeal. The latter is characterized by nodal diameters rotating during a squeal cycle. A linear reduced model, able to reproduce the dynamic behavior of the experimental setup, is used to predict the squeal occurrence. However, such linear model is not able to predict the rotating squeal characteristic that seems to be caused by nonlinear interactions due to the contact between the disc and the caliper.

  7. Generation of Nanoparticles from Friction between Railway Brake Disks and Pads.

    PubMed

    Namgung, Hyeong-Gyu; Kim, Jong-Bum; Woo, Sang-Hee; Park, Sechan; Kim, Minhae; Kim, Min-Soo; Bae, Gwi-Nam; Park, Duckshin; Kwon, Soon-Bark

    2016-04-01

    In this study, we measured the size distribution of particles ranging in size from 5.6 to 560 nm that were emitted between brake disks and pads under various braking conditions to observe and analyze changes to the resulting particle size distribution over braking time. A peak of 178-275 nm (200 nm peak) was observed in all braking conditions. However, the generation of spherical particles of a 10 nm range was observed only when the disk speed and brake force were above certain levels and intensified only when speed and brake force further increased. The total number concentration of ultrafine particles (no larger than 0.1 μm; PM0.1) generated was found to correlate with disk speed and brake force. Thus, the generation of nanoparticles resulting from disk speed and brake force was attributable primarily to increases in the contact surface temperature. The critical temperature for the generation of nanoparticles of a 10 nm range was found to be about 70 °C, which is the average temperature between the surface and the inside of the disk. If the speed or brake force was higher, that is, the temperature of the contact surface reached a certain level, evaporation and condensation took place. Vapor then left the friction surface, met with the air, and quickly cooled to form nanoparticles through nucleation. When the newly generated particles became highly concentrated, they grew through coagulation to form agglomerates or the vapor condensed directly onto the surface of existing particles of about 200 nm (formed by mechanical friction). PMID:26967707

  8. Falling Magnets and Electromagnetic Braking

    NASA Astrophysics Data System (ADS)

    Culbreath, Christopher; Palffy-Muhoray, Peter

    2009-03-01

    The slow fall of a rare earth magnet through a copper pipe is a striking example of electromagnetic braking; this remarkable phenomenon has been the subject of a number of scientific paper s [1, 2]. In a pipe having radius R and wall thickness D, the terminal velocity of the falling magnet is proportional to (R̂4)/D. It is interesting to ask what happens in the limit as D becomes very large. We report our experimental observations and theoretical predictions of the dependence of the terminal velocity on pipe radius R for large D. [1] Y. Levin, F.L. da Silveira, and F.B. Rizzato, ``Electromagnetic braking: A simple quantitative model''. American Journal of Physics, 74(9): p. 815-817 (2006). [2] J.A. Pelesko, M. Cesky, and S. Huertas, Lenz's law and dimensional analysis. American Journal of Physics, 3(1): p. 37-39. 2005.

  9. Electromagnetic braking for Mars spacecraft

    NASA Technical Reports Server (NTRS)

    Holt, A. C.

    1986-01-01

    Aerobraking concepts are being studied to improve performance and cost effectiveness of propulsion systems for Mars landers and Mars interplanetary spacecraft. Access to megawatt power levels (nuclear power coupled to high-storage inductive or capacitive devices) on a manned Mars interplanetary spacecraft may make feasible electromagnetic braking and lift modulation techniques which were previously impractical. Using pulsed microwave and magnetic field technology, potential plasmadynamic braking and hydromagnetic lift modulation techniques have been identified. Entry corridor modulation to reduce loads and heating, to reduce vertical descent rates, and to expand horizontal and lateral landing ranges are possible benefits. In-depth studies are needed to identify specific design concepts for feasibility assessments. Standing wave/plasma sheath interaction techniques appear to be promising. The techniques may require some tailoring of spacecraft external structures and materials. In addition, rapid response guidance and control systems may require the use of structurally embedded sensors coupled to expert systems or to artificial intelligence systems.

  10. Design principles of descent vehicles with an inflatable braking device

    NASA Astrophysics Data System (ADS)

    Alexashkin, S. N.; Pichkhadze, K. M.; Finchenko, V. S.

    2013-12-01

    A new type of descent vehicle (DVs) is described: a descent vehicle with an inflatable braking device (IBD DV). IBD development issues, as well as materials needed for the design, manufacturing, and testing of an IBD and its thermal protection, are discussed. A list is given of Russian integrated test facilities intended for testing IBD DVs. Progress is described in the development of IBD DVs in Russia and abroad.

  11. What brakes the Crab pulsar?

    NASA Astrophysics Data System (ADS)

    Čadež, A.; Zampieri, L.; Barbieri, C.; Calvani, M.; Naletto, G.; Barbieri, M.; Ponikvar, D.

    2016-03-01

    Context. Optical observations provide convincing evidence that the optical phase of the Crab pulsar follows the radio one closely. Since optical data do not depend on dispersion measure variations, they provide a robust and independent confirmation of the radio timing solution. Aims: The aim of this paper is to find a global mathematical description of Crab pulsar's phase as a function of time for the complete set of published Jodrell Bank radio ephemerides (JBE) in the period 1988-2014. Methods: We apply the mathematical techniques developed for analyzing optical observations to the analysis of JBE. We break the whole period into a series of episodes and express the phase of the pulsar in each episode as the sum of two analytical functions. The first function is the best-fitting local braking index law, and the second function represents small residuals from this law with an amplitude of only a few turns, which rapidly relaxes to the local braking index law. Results: From our analysis, we demonstrate that the power law index undergoes "instantaneous" changes at the time of observed jumps in rotational frequency (glitches). We find that the phase evolution of the Crab pulsar is dominated by a series of constant braking law episodes, with the braking index changing abruptly after each episode in the range of values between 2.1 and 2.6. Deviations from such a regular phase description behave as oscillations triggered by glitches and amount to fewer than 40 turns during the above period, in which the pulsar has made more than 2 × 1010 turns. Conclusions: Our analysis does not favor the explanation that glitches are connected to phenomena occurring in the interior of the pulsar. On the contrary, timing irregularities and changes in slow down rate seem to point to electromagnetic interaction of the pulsar with the surrounding environment.

  12. Ground-based air-sampling measurements near the Nevada Test Site after atmospheric nuclear tests.

    PubMed

    Cederwall, R T; Ricker, Y E; Cederwall, P L; Homan, D N; Anspaugh, L R

    1990-11-01

    Historical air-sampling data measured within 320 km (200 mi) of the Nevada Test Site (NTS) have been reviewed for periods following atmospheric nuclear tests, primarily in the 1950s. These data come mostly from high-volume air samplers, with some from cascade-impactor samplers. Measurements considered here are for beta radiation from gross fission products. The resulting air-quality data base is comprised of almost 13,000 samples from 42 sampling locations downwind of the NTS. In order to compile an accurate air-quality data base for use in estimating exposure via inhalation, raw data values were sought where possible, and the required calculations were performed on a computer with state-of-the-art algorithms. The data-processing procedures consisted of (1) entry and error checking of historical data; (2) determination of appropriate background values, air-sampling volumes, and net air concentrations; and (3) calculation of integrated air concentration (C) for each sample (considering fallout arrival times). Comparing C values for collocated high-volume and cascade-impactor samplers during the Upshot-Knothole series showed similar lognormal distributions, but with a geometric mean C for cascade impactors about half that for the high-volume air samplers. Overall, the uncertainty in C values is about a factor of three. In the past, it has been assumed that C could be related to ground deposition by a constant having units of velocity. In our data bases, simultaneous measurements of air concentration and ground deposition at the same locations were not related by a constant; indeed, there was a great amount of scatter. This suggests that the relationship between C and ground deposition in this situation is too complex to be treated adequately by simple approaches. PMID:2211113

  13. Ground-based air-sampling measurements near the Nevada Test Site after atmospheric nuclear tests

    SciTech Connect

    Cederwall, R.T.; Ricker, Y.E.; Cederwall, P.L.; Homan, D.N.; Anspaugh, L.R. )

    1990-11-01

    Historical air-sampling data measured within 320 km (200 mi) of the Nevada Test Site (NTS) have been reviewed for periods following atmospheric nuclear tests, primarily in the 1950s. These data come mostly from high-volume air samplers, with some from cascade-impactor samplers. Measurements considered here are for beta radiation from gross fission products. The resulting air-quality data base is comprised of almost 13,000 samples from 42 sampling locations downwind of the NTS. In order to compile an accurate air-quality data base for use in estimating exposure via inhalation, raw data values were sought where possible, and the required calculations were performed on a computer with state-of-the-art algorithms. The data-processing procedures consisted of (1) entry and error checking of historical data; (2) determination of appropriate background values, air-sampling volumes, and net air concentrations; and (3) calculation of integrated air concentration (C) for each sample (considering fallout arrival times). Comparing C values for collocated high-volume and cascade-impactor samplers during the Upshot-Knothole series showed similar lognormal distributions, but with a geometric mean C for cascade impactors about half that for the high-volume air samplers. Overall, the uncertainty in C values is about a factor of three. In the past, it has been assumed that C could be related to ground deposition by a constant having units of velocity. In our data bases, simultaneous measurements of air concentration and ground deposition at the same locations were not related by a constant; indeed, there was a great amount of scatter. This suggests that the relationship between C and ground deposition in this situation is too complex to be treated adequately by simple approaches.

  14. The Effect of a Variable Disc Pad Friction Coefficient for the Mechanical Brake System of a Railway Vehicle

    PubMed Central

    Lee, Nam-Jin; Kang, Chul-Goo

    2015-01-01

    A brake hardware-in-the-loop simulation (HILS) system for a railway vehicle is widely applied to estimate and validate braking performance in research studies and field tests. When we develop a simulation model for a full vehicle system, the characteristics of all components are generally properly simplified based on the understanding of each component’s purpose and interaction with other components. The friction coefficient between the brake disc and the pad used in simulations has been conventionally considered constant, and the effect of a variable friction coefficient is ignored with the assumption that the variability affects the performance of the vehicle braking very little. However, the friction coefficient of a disc pad changes significantly within a range due to environmental conditions, and thus, the friction coefficient can affect the performance of the brakes considerably, especially on the wheel slide. In this paper, we apply a variable friction coefficient and analyzed the effects of the variable friction coefficient on a mechanical brake system of a railway vehicle. We introduce a mathematical formula for the variable friction coefficient in which the variable friction is represented by two variables and five parameters. The proposed formula is applied to real-time simulations using a brake HILS system, and the effectiveness of the formula is verified experimentally by testing the mechanical braking performance of the brake HILS system. PMID:26267883

  15. The Effect of a Variable Disc Pad Friction Coefficient for the Mechanical Brake System of a Railway Vehicle.

    PubMed

    Lee, Nam-Jin; Kang, Chul-Goo

    2015-01-01

    A brake hardware-in-the-loop simulation (HILS) system for a railway vehicle is widely applied to estimate and validate braking performance in research studies and field tests. When we develop a simulation model for a full vehicle system, the characteristics of all components are generally properly simplified based on the understanding of each component's purpose and interaction with other components. The friction coefficient between the brake disc and the pad used in simulations has been conventionally considered constant, and the effect of a variable friction coefficient is ignored with the assumption that the variability affects the performance of the vehicle braking very little. However, the friction coefficient of a disc pad changes significantly within a range due to environmental conditions, and thus, the friction coefficient can affect the performance of the brakes considerably, especially on the wheel slide. In this paper, we apply a variable friction coefficient and analyzed the effects of the variable friction coefficient on a mechanical brake system of a railway vehicle. We introduce a mathematical formula for the variable friction coefficient in which the variable friction is represented by two variables and five parameters. The proposed formula is applied to real-time simulations using a brake HILS system, and the effectiveness of the formula is verified experimentally by testing the mechanical braking performance of the brake HILS system. PMID:26267883

  16. 49 CFR 570.56 - Vacuum brake assist unit and vacuum brake system.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... vacuum brakes shall operate in conjunction with the truck or truck tractor brake pedal. (2) Inspection procedure. (i) Check the trailer vacuum system by coupling trailer(s) to truck or truck tractor and...

  17. Spring- And Air-Suspension Mechanism For Testing Structures

    NASA Technical Reports Server (NTRS)

    Woodard, Stanley E.

    1994-01-01

    Spring-and air-suspension mechanism supports weight of one end of test structure, yet allows that end to move almost completely unhindered as though it were weightless and not attached to suspension. Mechanisms of this type called "zero-spring-rate mechanisms" (ZSRM's) because they support structure in manner of spring suspension exhibiting approximately zero stiffness (zero spring rate) within some range of motion about nominal equilibrium or central support position. This suspension mechanism does not include overhead cables, which necessitate large amounts of overhead clearance and overhead support structures: suspension mechanism more compact (much smaller than structure) and supports structure from below.

  18. Frictional and heat resistance characteristics of coconut husk particle filled automotive brake pad

    NASA Astrophysics Data System (ADS)

    Bahari, Shahril Anuar; Chik, Mohd Syahrizul; Kassim, Masitah Abu; Som Said, Che Mohamad; Misnon, Mohd Iqbal; Mohamed, Zulkifli; Othman, Eliasidi Abu

    2012-06-01

    The objective of this study was to determine the friction and heat resistance characteristics of automotive brake pad composed with different sizes and percentages of coconut husk particle. The materials used were phenolic resin (phenol formaldehyde) as binder, copper, graphite and brass as friction producer/modifiers, magnesium oxide as abrasive material, steel and barium sulfate as reinforcement while coconut husk particle as filler. To obtain particle, the coconut husk was ground and dried to 3% moisture content. Then the coconut husk particle was screened using 80 mesh (to obtain coarse dust) and 100 mesh (to obtain fine dust). Different percentages of particle, such as 10 and 30% were used in the mixture of brake pad materials. Then the mixture was hot-pressed to produce brake pad. Chase machine was used to determine the friction coefficient in friction resistance testing, while thermogravimetric analyzer (TGA) machine was used to determine the heat decomposition values in heat resistance testing. Results showed that brake pad with 100 mesh and 10% composition of coconut husk particle showed the highest friction coefficient. For heat resistance, brake pad with 100 mesh and 30% composition of coconut husk dust showed the highest decomposition temperature, due to the high percentage of coconut husk particle in the composition, thus increased the thermal stability. As a comparison, brake pad composed with coconut husk particle showed better heat resistance results than commercial brake pad.

  19. VAPOR SPACE AND LIQUID/AIR INTERFACECORROSION TESTS

    SciTech Connect

    Zapp, P.; Hoffman, E.

    2009-11-09

    The phenomena of vapor space corrosion and liquid/air interface corrosion of carbon steel in simulated liquid waste environments have been investigated. Initial experiments have explored the hypothesis that vapor space corrosion may be accelerated by the formation of a corrosive electrolyte on the tank wall by a process of evaporation of relatively warmer waste and condensation of the vapor on the relatively cooler tank wall. Results from initial testing do not support the hypothesis of electrolyte transport by evaporation and condensation. The analysis of the condensate collected by a steel specimen suspended over a 40 C simulated waste solution showed no measurable concentrations of the constituents of the simulated solution and a decrease in pH from 14 in the simulant to 5.3 in the condensate. Liquid/air interface corrosion was studied as a galvanic corrosion system, where steel at the interface undergoes accelerated corrosion while steel in contact with bulk waste is protected. The zero-resistance-ammeter technique was used to measure the current flow between steel specimens immersed in solutions simulating (1) the high-pH bulk liquid waste and (2) the expected low-pH meniscus liquid at the liquid/air interface. Open-circuit potential measurements of the steel specimens were not significantly different in the two solutions, with the result that (1) no consistent galvanic current flow occurred and (2) both the meniscus specimen and bulk specimen were subject to pitting corrosion.

  20. LIQUID AIR INTERFACE CORROSION TESTING FOR FY2010

    SciTech Connect

    Zapp, P.

    2010-12-16

    An experimental study was undertaken to investigate the corrosivity to carbon steel of the liquid-air interface of dilute simulated radioactive waste solutions. Open-circuit potentials were measured on ASTM A537 carbon steel specimens located slightly above, at, and below the liquid-air interface of simulated waste solutions. The 0.12-inch-diameter specimens used in the study were sized to respond to the assumed distinctive chemical environment of the liquid-air interface, where localized corrosion in poorly inhibited solutions may frequently be observed. The practical inhibition of such localized corrosion in liquid radioactive waste storage tanks is based on empirical testing and a model of a liquid-air interface environment that is made more corrosive than the underlying bulk liquid due to chemical changes brought about by absorbed atmospheric carbon dioxide. The chemical changes were assumed to create a more corrosive open-circuit potential in carbon in contact with the liquid-air interface. Arrays of 4 small specimens spaced about 0.3 in. apart were partially immersed so that one specimen contacted the top of the meniscus of the test solution. Two specimens contacted the bulk liquid below the meniscus and one specimen was positioned in the vapor space above the meniscus. Measurements were carried out for up to 16 hours to ensure steady-state had been obtained. The results showed that there was no significant difference in open-circuit potentials between the meniscus-contact specimens and the bulk-liquid-contact specimens. With the measurement technique employed, no difference was detected between the electrochemical conditions of the meniscus versus the bulk liquid. Stable open-circuit potentials were measured on the specimen located in the vapor space above the meniscus, showing that there existed an electrochemical connection through a thin film of solution extending up from the meniscus. This observation supports the Hobbs-Wallace model of the development

  1. Experimental study using infrared thermography on the convective heat transfer of a TGV brake disc in the actual environment

    NASA Astrophysics Data System (ADS)

    Siroux, Monica; Harmand, Souad; Desmet, Bernard

    2001-03-01

    Local and mean convective heat transfer from a rotating TGV brake disc model in the actual environment and submitted to an air flow parallel to the disc surface is studied experimentally in this paper. The experimental technique is based on the use of a heated thermally thick disc combined with the technique of temperature measurement by infrared thermography. The local convective heat transfer coefficient from the disc surface is identified by solving the steady state heat equation by finite difference method using the experimental temperature distribution as boundary conditions. These tests were carried out for rotational speed (omega) between 325 and 2000 rpm (rotational Reynolds number Re between 88500 and 545000) so as to obtain laminar and turbulent flow on the disc, and for air flow velocity U ranging between 0 and 12 m s-1 (air flow Reynolds number Re0 between 0 and 153000).

  2. The Yucca Mountain Project prototype air-coring test, U12g tunnel, Nevada test site

    SciTech Connect

    Ray, J.M.; Newsom, J.C.

    1994-12-01

    The Prototype Air-Coring Test was conducted at the Nevada Test Site (NTS) G-Tunnel facility to evaluate standard coring techniques, modified slightly for air circulation, for use in testing at a prospective nuclear waste repository at Yucca Mountain, Nevada. Air-coring technology allows sampling of subsurface lithology with minimal perturbation to ambient characteristic such as that required for exploratory holes near aquifers, environmental applications, and site characterization work. Two horizontal holes were cored, one 50 ft long and the other 150 ft long, in densely welded fractured tuff to simulate the difficult drilling conditions anticipated at Yucca Mountain. Drilling data from seven holes on three other prototype tests in nonwelded tuff were also collected for comparison. The test was used to establish preliminary standards of performance for drilling and dust collection equipment and to assess procedural efficiencies. The Longyear-38 drill achieved 97% recovery for HQ-size core (-2.5 in.), and the Atlas Copco dust collector (DCT-90) captured 1500 lb of fugitive dust in a mine environment with only minor modifications. Average hole production rates were 6-8 ft per 6-h shift in welded tuff and almost 20 ft per shift on deeper holes in nonwelded tuff. Lexan liners were successfully used to encapsulate core samples during the coring process and protect core properties effectively. The Prototype Air-Coring Test demonstrated that horizontal air coring in fractured welded tuff (to at least 150 ft) can be safely accomplished by proper selection, integration, and minor modification of standard drilling equipment, using appropriate procedures and engineering controls. The test also indicated that rig logistics, equipment, and methods need improvement before attempting a large-scale dry drilling program at Yucca Mountain.

  3. Dynamics of Braking Vehicles: From Coulomb Friction to Anti-Lock Braking Systems

    ERIC Educational Resources Information Center

    Tavares, J. M.

    2009-01-01

    The dynamics of braking of wheeled vehicles is studied using the Coulomb approximation for the friction between road and wheels. The dependence of the stopping distance on the mass of the vehicle, on the number of its wheels and on the intensity of the braking torque is established. It is shown that there are two regimes of braking, with and…

  4. Bidirectional Drive-And-Brake Mechanism

    NASA Technical Reports Server (NTRS)

    Swan, Scott A.

    1991-01-01

    Vehicle that crawls along monorail combines features of both bicycle and railroad handcar. Bidirectional drive-and-brake mechanism includes selectable-pawl-and-ratchet overrunning clutch (drive mechanism) and mating stationary and rotating conical surfaces pressing against each other (brake mechanism). Operates similarly to bicycle drive-and-brake mechanism except limits rotation of sprocket in both directions and brakes at both limits. Conceived for use by astronaut traveling along structure in outer space, concept also applied on Earth to make very small railraod handcars or crawling vehicles for use on large structures, in pipelines under construction, or underwater.

  5. 49 CFR 236.701 - Application, brake; full service.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... a split reduction in brake pipe pressure at a service rate until maximum brake cylinder pressure is... other than emergency which develops the maximum brake cylinder pressure, as determined by the design...

  6. 49 CFR 393.43 - Breakaway and emergency braking.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ..., separate. (c) Emergency brake requirements, vacuum brakes. Every truck tractor and truck when used for towing other vehicles equipped with vacuum brakes, shall have, in addition to the single control...

  7. Remote sensing and sensor testing via hot air balloons

    SciTech Connect

    Watson, S.M.; Kroutil, R.T.; Traynor, C.A.

    1996-11-01

    Tethered and free-flying manned hot air balloons have been demonstrated as platforms for various remote sensing asks and sensor testing and atmospheric measurements. These platforms are inexpensive to operate, do not cause atmospheric disturbances as do higher speed platforms, and are extremely stable and free of vibrations inherent in aircraft structures. The equipment operated and tested on the balloons in connection with this project includes a prototype multispectral imaging spectrometer, high resolution CCD cameras, mid- and far-infrared cameras, a radiometer, FTIR spectrometers, video recording equipment and portable power generators carried beneath the balloon providing power to the equipment The experiments conducted on and from the balloon include chemical effluents characterization, atmospheric propagation through slant paths, obscurants imaging and scene reflectance. 7 refs.

  8. Wear and related characteristics of an aircraft tire during braking

    NASA Technical Reports Server (NTRS)

    Mccarty, J. L.

    1972-01-01

    Wear and related characteristics of friction and temperature developed during braking of size 22 x 5.5, type aircraft tires are studied. The testing technique involved gearing the tire to a driving wheel of a ground vehicle to provide operations at constant slip ratios on asphalt, concrete, and slurry-seal surfaces. Data were obtained over the range of slip ratios generally attributed to an aircraft braking system during dry runway operations. The results show that the cumulative tire wear varies linearly with distance traveled and the wear rate increases with increasing slip ratio and is influenced by the runway-surface character. Differences in the wear rates associated with the various surfaces suggest that runways can be rated on the basis of tire wear. The results also show that the friction coefficients developed during fixed-slip-ratio operations are in good agreement with those obtained by other investigators during cyclic braking, in that the dry friction is insensitive to the tire tread temperature is shown to increase with increasing slip ratio and, at the higher ratios, to be greater during braking on asphalt and slurry seal than on concrete.

  9. 30 CFR 75.152 - Tests of air flow; qualified person.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Tests of air flow; qualified person. 75.152....152 Tests of air flow; qualified person. A person is a qualified person within the meaning of the provisions of Subpart D—Ventilation of this part requiring that tests of air flow be made by a...

  10. 78 FR 17185 - U.S. Air Force Space Command Notice of Test

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-20

    ... Department of the Air Force U.S. Air Force Space Command Notice of Test AGENCY: U.S. Air Force Space Command... inform users of an upcoming event related to the GPS satellite constellation. U.S. Air Force Space... process L2C or L5 CNAV. U.S. Air Force Space Command ] expects to conduct one to two CNAV tests per...

  11. Piezoelectric-hydraulic pump based band brake actuation system for automotive transmission control

    NASA Astrophysics Data System (ADS)

    Kim, Gi-Woo; Wang, K. W.

    2007-04-01

    The actuation system of friction elements (such as band brakes) is essential for high quality operations in modern automotive automatic transmissions (in short, ATs). The current band brake actuation system consists of several hydraulic components, including the oil pump, the regulating valve and the control valves. In general, it has been recognized that the current AT band brake actuation system has many limitations. For example, the oil pump and valve body are relatively heavy and complex. Also, the oil pumps induce inherently large drag torque, which affects fuel economy. This research is to overcome these problems of the current system by exploring the utilization of a hybrid type piezo-hydraulic pump device for AT band brake control. This new actuating system integrates a piezo-hydraulic pump to the input of the band brake. Compared with the current systems, this new actuator features much simpler structure, smaller size, and lower weight. This paper describes the development, design and fabrication of the new stand-alone prototype actuator for AT band brake control. An analytical model is developed and validated using experimental data. Performance tests on the hardware and system simulations utilizing the validated model are performed to characterize the new prototype actuator. It is predicted that with increasing of accumulator pressure and driving frequency, the proposed prototype actuating system will satisfy the band brake requirement for AT shift control.

  12. Design and evaluation of a novel magnetorheological brake with coils placed on the side housings

    NASA Astrophysics Data System (ADS)

    Nguyen, Quoc Hung; Diep Nguyen, Ngoc; Bok Choi, Seung

    2015-04-01

    In the design of a traditional magnetorheological brake (MRB), coils are often placed on the cylindrical housing of the brake. This results in many disadvantages such as a ‘bottle-neck’ problem of magnetic flux. Moreover, in this design a nonmagnetic bobbin is required, and difficulties in manufacturing and maintenance exist. In order to resolve this problem, in this study a new configuration of MRB with coils placed on the side housings of the brake is proposed, optimally designed and experimentally evaluated. After describing an introduction of the proposed configuration, braking torque of the MRB is analyzed based on the Bingham-plastic rheological model of magnetorheological fluid (MRF). The optimization of the proposed and conventional MRBs is then performed considering maximum braking torque and mass of the brakes. In the optimization, both rectangular and polygonal shapes of the brake housing are considered. Based on the optimal results, a comparison of the performance characteristics of the proposed MRB and the conventional one is undertaken. In addition, an experimental test of the MRBs is conducted, and the results are presented in order to validate the performance characteristics of the proposed MRB.

  13. A method to model anticipatory postural control in driver braking events.

    PubMed

    Östh, Jonas; Eliasson, Erik; Happee, Riender; Brolin, Karin

    2014-09-01

    Human body models (HBMs) for vehicle occupant simulations have recently been extended with active muscles and postural control strategies. Feedback control has been used to model occupant responses to autonomous braking interventions. However, driver postural responses during driver initiated braking differ greatly from autonomous braking. In the present study, an anticipatory postural response was hypothesized, modelled in a whole-body HBM with feedback controlled muscles, and validated using existing volunteer data. The anticipatory response was modelled as a time dependent change in the reference value for the feedback controllers, which generates correcting moments to counteract the braking deceleration. The results showed that, in 11 m/s(2) driver braking simulations, including the anticipatory postural response reduced the peak forward displacement of the head by 100mm, of the shoulder by 30 mm, while the peak head flexion rotation was reduced by 18°. The HBM kinematic response was within a one standard deviation corridor of corresponding test data from volunteers performing maximum braking. It was concluded that the hypothesized anticipatory responses can be modelled by changing the reference positions of the individual joint feedback controllers that regulate muscle activation levels. The addition of anticipatory postural control muscle activations appears to explain the difference in occupant kinematics between driver and autonomous braking. This method of modelling postural reactions can be applied to the simulation of other driver voluntary actions, such as emergency avoidance by steering. PMID:25174533

  14. Research on Heat-Mechanical Coupling of Ventilated Disc Brakes under the Condition of Emergency Braking

    NASA Astrophysics Data System (ADS)

    Tan, Xuelong; Zhang, Jian; Tang, Wenxian; Zhang, Yang

    Taking the ventilated disc brake in some company as research object, and using UG to build 3D models of brake disc and pad, and making use of ABAQUS/Standard to set up two parts' finite element model, via the decelerated motion of actual simulation brake disc, which gets ventilated disc brake in the case of emergency breaking in time and space distribution of conditions of temperature and stress field, summarizes the distribution of temperature field and stress field, proves complex coupling between temperature, stress, and supplies the direct basis for brake's fatigue life analysis.

  15. Braking index of isolated pulsars

    NASA Astrophysics Data System (ADS)

    Hamil, O.; Stone, J. R.; Urbanec, M.; Urbancová, G.

    2015-03-01

    Isolated pulsars are rotating neutron stars with accurately measured angular velocities Ω , and their time derivatives that show unambiguously that the pulsars are slowing down. Although the exact mechanism of the spin-down is a question of detailed debate, the commonly accepted view is that it arises through emission of magnetic dipole radiation (MDR) from a rotating magnetized body. Other processes, including the emission of gravitational radiation, and of relativistic particles (pulsar wind), are also being considered. The calculated energy loss by a rotating pulsar with a constant moment of inertia is assumed proportional to a model dependent power of Ω . This relation leads to the power law Ω ˙ =-K Ωn where n is called the braking index. The MDR model predicts n exactly equal to 3. Selected observations of isolated pulsars provide rather precise values of n , individually accurate to a few percent or better, in the range 1 braking index within the MDR model. Four microscopic equations of state are employed as input to two different computational codes that solve Einstein's equations numerically, either exactly or using the perturbative Hartle-Thorne method, to calculate the

  16. Air

    MedlinePlus

    ... do to protect yourself from dirty air . Indoor air pollution and outdoor air pollution Air can be polluted indoors and it can ... this chart to see what things cause indoor air pollution and what things cause outdoor air pollution! Indoor ...

  17. Position control optimization of aerodynamic brake device for high-speed trains

    NASA Astrophysics Data System (ADS)

    Zuo, Jianyong; Luo, Zhuojun; Chen, Zhongkai

    2014-03-01

    The aerodynamic braking is a clean and non-adhesion braking, and can be used to provide extra braking force during high-speed emergency braking. The research of aerodynamic braking has attracted more and more attentions in recent years. However, most researchers in this field focus on aerodynamic effects and seldom on issues of position control of the aerodynamic braking board. The purpose of this paper is to explore position control optimization of the braking board in an aerodynamic braking prototype. The mathematical models of the hydraulic drive unit in the aerodynamic braking system are analyzed in detail, and the simulation models are established. Three control functions—constant, linear, and quadratic—are explored. Two kinds of criteria, including the position steady-state error and the acceleration of the piston rod, are used to evaluate system performance. Simulation results show that the position steady state-error is reduced from around 12-2 mm by applying a linear instead of a constant function, while the acceleration is reduced from 25.71-3.70 m/s2 with a quadratic control function. Use of the quadratic control function is shown to improve system performance. Experimental results obtained by measuring the position response of the piston rod on a test-bench also suggest a reduced position error and smooth movement of the piston rod. This implies that the acceleration is smaller when using the quadratic function, thus verifying the effectiveness of control schemes to improve to system performance. This paper proposes an effective and easily implemented control scheme that improves the position response of hydraulic cylinders during position control.

  18. 14 CFR 25.507 - Reversed braking.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Reversed braking. 25.507 Section 25.507 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Structure Ground Loads § 25.507 Reversed braking. (a) The airplane must be in a three point static...

  19. 14 CFR 25.507 - Reversed braking.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Reversed braking. 25.507 Section 25.507 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Structure Ground Loads § 25.507 Reversed braking. (a) The airplane must be in a three point static...

  20. 14 CFR 25.507 - Reversed braking.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Reversed braking. 25.507 Section 25.507 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Structure Ground Loads § 25.507 Reversed braking. (a) The airplane must be in a three point static...

  1. 14 CFR 25.507 - Reversed braking.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Reversed braking. 25.507 Section 25.507 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Structure Ground Loads § 25.507 Reversed braking. (a) The airplane must be in a three point static...

  2. 14 CFR 25.507 - Reversed braking.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Reversed braking. 25.507 Section 25.507 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Structure Ground Loads § 25.507 Reversed braking. (a) The airplane must be in a three point static...

  3. 49 CFR 238.231 - Brake system.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Brake system. 238.231 Section 238.231 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION PASSENGER EQUIPMENT SAFETY STANDARDS Specific Requirements for Tier I Passenger Equipment § 238.231 Brake system. Except...

  4. 14 CFR 23.735 - Brakes.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... main wheel brake assembly must not be less than the kinetic energy absorption requirements determined under either of the following methods: (1) The brake kinetic energy absorption requirements must be... design landing weight. (2) Instead of a rational analysis, the kinetic energy absorption requirements...

  5. 14 CFR 23.735 - Brakes.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... main wheel brake assembly must not be less than the kinetic energy absorption requirements determined under either of the following methods: (1) The brake kinetic energy absorption requirements must be... design landing weight. (2) Instead of a rational analysis, the kinetic energy absorption requirements...

  6. 49 CFR 236.712 - Brake pipe.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Brake pipe. 236.712 Section 236.712 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF... OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Definitions § 236.712 Brake pipe. A...

  7. 49 CFR 393.52 - Brake performance.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 5 2013-10-01 2013-10-01 false Brake performance. 393.52 Section 393.52 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL MOTOR CARRIER SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION FEDERAL MOTOR CARRIER SAFETY REGULATIONS PARTS AND ACCESSORIES NECESSARY FOR SAFE OPERATION Brakes § 393.52...

  8. Constraining the braking indices of magnetars

    NASA Astrophysics Data System (ADS)

    Gao, Z. F.; Li, X.-D.; Wang, N.; Yuan, J. P.; Wang, P.; Peng, Q. H.; Du, Y. J.

    2016-02-01

    Because of the lack of long-term pulsed emission in quiescence and the strong timing noise, it is impossible to directly measure the braking index n of a magnetar. Based on the estimated ages of their potentially associated supernova remnants (SNRs), we estimate the values of the mean braking indices of eight magnetars with SNRs, and find that they cluster in the range of 1-42. Five magnetars have smaller mean braking indices of 1 < n < 3, and we interpret them within a combination of magneto-dipole radiation and wind-aided braking. The larger mean braking indices of n > 3 for the other three magnetars are attributed to the decay of external braking torque, which might be caused by magnetic field decay. We estimate the possible wind luminosities for the magnetars with 1 < n < 3, and the dipolar magnetic field decay rates for the magnetars with n > 3, within the updated magneto-thermal evolution models. Although the constrained range of the magnetars' braking indices is tentative, as a result of the uncertainties in the SNR ages due to distance uncertainties and the unknown conditions of the expanding shells, our method provides an effective way to constrain the magnetars' braking indices if the measurements of the SNR ages are reliable, which can be improved by future observations.

  9. 14 CFR 27.921 - Rotor brake.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Rotor brake. 27.921 Section 27.921... STANDARDS: NORMAL CATEGORY ROTORCRAFT Powerplant Rotor Drive System § 27.921 Rotor brake. If there is a means to control the rotation of the rotor drive system independently of the engine, any limitations...

  10. 14 CFR 29.921 - Rotor brake.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Rotor brake. 29.921 Section 29.921... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Powerplant Rotor Drive System § 29.921 Rotor brake. If there is a means to control the rotation of the rotor drive system independently of the engine, any limitations...

  11. Orbital-Transfer Vehicle With Aerodynamic Braking

    NASA Technical Reports Server (NTRS)

    Scott, C. D.; Nagy, K.; Roberts, B. B.; Ried, R. C.; Kroll, K.; Gamble, J.

    1986-01-01

    Vehicle includes airbrake for deceleration into lower orbit. Report describes vehicle for carrying payloads between low and high orbits around Earth. Vehicle uses thin, upper atmosphere for braking when returning to low orbit. Since less propellant needed than required for full retrorocket braking, vehicle carries larger payload and therefore reduces cost of space transportation.

  12. 49 CFR 238.231 - Brake system.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Brake system. 238.231 Section 238.231 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION PASSENGER EQUIPMENT SAFETY STANDARDS Specific Requirements for Tier I Passenger Equipment § 238.231 Brake system. Except...

  13. 14 CFR 27.735 - Brakes.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Brakes. 27.735 Section 27.735 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT Design and Construction Landing Gear § 27.735 Brakes. For...

  14. 14 CFR 29.921 - Rotor brake.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Rotor brake. 29.921 Section 29.921 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Powerplant Rotor Drive System § 29.921 Rotor brake. If there is...

  15. 14 CFR 27.921 - Rotor brake.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Rotor brake. 27.921 Section 27.921 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT Powerplant Rotor Drive System § 27.921 Rotor brake. If there is...

  16. 14 CFR 29.921 - Rotor brake.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Rotor brake. 29.921 Section 29.921 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Powerplant Rotor Drive System § 29.921 Rotor brake. If there is...

  17. 14 CFR 27.735 - Brakes.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Brakes. 27.735 Section 27.735 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT Design and Construction Landing Gear § 27.735 Brakes. For...

  18. 14 CFR 29.735 - Brakes.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Brakes. 29.735 Section 29.735 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction Landing Gear § 29.735 Brakes....

  19. 14 CFR 29.921 - Rotor brake.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Rotor brake. 29.921 Section 29.921 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Powerplant Rotor Drive System § 29.921 Rotor brake. If there is...

  20. 14 CFR 29.735 - Brakes.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Brakes. 29.735 Section 29.735 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction Landing Gear § 29.735 Brakes....

  1. 14 CFR 27.921 - Rotor brake.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Rotor brake. 27.921 Section 27.921 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT Powerplant Rotor Drive System § 27.921 Rotor brake. If there is...

  2. 14 CFR 27.921 - Rotor brake.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Rotor brake. 27.921 Section 27.921 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT Powerplant Rotor Drive System § 27.921 Rotor brake. If there is...

  3. 14 CFR 29.735 - Brakes.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Brakes. 29.735 Section 29.735 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction Landing Gear § 29.735 Brakes....

  4. 14 CFR 29.921 - Rotor brake.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Rotor brake. 29.921 Section 29.921 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Powerplant Rotor Drive System § 29.921 Rotor brake. If there is...

  5. 14 CFR 27.921 - Rotor brake.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Rotor brake. 27.921 Section 27.921 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT Powerplant Rotor Drive System § 27.921 Rotor brake. If there is...

  6. 14 CFR 27.735 - Brakes.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Brakes. 27.735 Section 27.735 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT Design and Construction Landing Gear § 27.735 Brakes. For...

  7. Air Conditioning Stall Phenomenon Testing, Model Development, and Simulation

    SciTech Connect

    Irminger, Philip; Rizy, D Tom; Li, Huijuan; Smith, Travis; Rice, C Keith; Li, Fangxing; Adhikari, Sarina

    2012-01-01

    Electric distribution systems are experiencing power quality issues of extended reduced voltage due to fault-induced delayed voltage recovery (FIDVR). FIDVR occurs in part because modern air conditioner (A/C) and heat pump compressor motors are much more susceptible to stalling during a voltage sag or dip such as a sub-transmission fault. They are more susceptible than older A/C compressor motors due to the low inertia of these newer and more energy efficient motors. There is a concern that these local reduced voltage events on the distribution system will become more frequent and prevalent and will combine over larger areas and challenge transmission system voltage and ultimately power grid reliability. The Distributed Energy Communications and Controls (DECC) Laboratory at Oak Ridge National Laboratory (ORNL) has been employed to (1) test, (2) characterize and (3) model the A/C stall phenomenon.

  8. Wear, friction, and temperature characteristics of an aircraft tire undergoing braking and cornering

    NASA Technical Reports Server (NTRS)

    Mccarty, J. L.; Yager, T. J.; Riccitiello, S. R.

    1979-01-01

    An investigation to evaluate the wear, friction, and temperature characteristics of aircraft tire treads fabricated from different elastomers is presented. The braking and cornering tests performed on aircraft tires retreaded with currently employed and experimental elastomers are described. The tread wear rate is discussed in relation to the slip ratio during braking and yaw angle during cornering. The extent of wear in either operational mode is examined in relation to the runway surface.

  9. Method and apparatus for electromagnetically braking a motor

    NASA Technical Reports Server (NTRS)

    Davis, Donald R. (Inventor); Radford, Nicolaus A (Inventor); Permenter, Frank Noble (Inventor); Parsons, Adam H (Inventor); Mehling, Joshua S (Inventor)

    2011-01-01

    An electromagnetic braking system and method is provided for selectively braking a motor using an electromagnetic brake having an electromagnet, a permanent magnet, a rotor assembly, and a brake pad. The brake assembly applies when the electromagnet is de-energized and releases when the electromagnet is energized. When applied the permanent magnet moves the brake pad into frictional engagement with a housing, and when released the electromagnet cancels the flux of the permanent magnet to allow a leaf spring to move the brake pad away from the housing. A controller has a DC/DC converter for converting a main bus voltage to a lower braking voltage based on certain parameters. The converter utilizes pulse-width modulation (PWM) to regulate the braking voltage. A calibrated gap is defined between the brake pad and permanent magnet when the brake assembly is released, and may be dynamically modified via the controller.

  10. Some wear studies on aircraft brake systems

    NASA Technical Reports Server (NTRS)

    Ho, T. L.

    1975-01-01

    An initial investigation of worn surfaces in friction pads and steel rotors used in current aircraft brakes was carried out using electron microprobe and X-ray diffraction analysis. It consists of the topographical study and the analysis of chemical element distribution. Based upon this initial examination, two approaches, microscopic and macroscopic have been conducted to interpret and formulate the wear mechanism of the aircraft brake materials. Microscopically, the wear particles were examined. The initiation and growth of surface cracks and the oxidation were emphasized in this investigation. Macroscopically, it has been found that, for the current copper based brake material sliding against 17-22 AS steel in a caliper brake, the surface temperature raised due to frictional heat is nonlinearly proportional to the load applied and slide time with speed at 1750 rpm. The wear of brake materials is then proportional to this temperature and is also a function of the melting temperature for copper.

  11. 40 CFR 86.162-03 - Approval of alternative air conditioning test simulations.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... alternative air conditioning test simulations. (a) Upon petition from a manufacturer or upon the Agency's own initiative, the Administrator will approve a simulation of the environmental cell for air conditioning test... the tailpipe emissions, air conditioning compressor load, and fuel economy. (2) For any...

  12. Driving and braking control of PM synchronous motor based on low-resolution hall sensor for battery electric vehicle

    NASA Astrophysics Data System (ADS)

    Gu, Jing; Ouyang, Minggao; Li, Jianqiu; Lu, Dongbin; Fang, Chuan; Ma, Yan

    2013-01-01

    Resolvers are normally employed for rotor positioning in motors for electric vehicles, but resolvers are expensive and vulnerable to vibrations. Hall sensors have the advantages of low cost and high reliability, but the positioning accuracy is low. Motors with Hall sensors are typically controlled by six-step commutation algorithm, which brings high torque ripple. This paper studies the high-performance driving and braking control of the in-wheel permanent magnetic synchronous motor (PMSM) based on low-resolution Hall sensors. Field oriented control (FOC) based on Hall-effect sensors is developed to reduce the torque ripple. The positioning accuracy of the Hall sensors is improved by interpolation between two consecutive Hall signals using the estimated motor speed. The position error from the misalignment of the Hall sensors is compensated by the precise calibration of Hall transition timing. The braking control algorithms based on six-step commutation and FOC are studied. Two variants of the six-step commutation braking control, namely, half-bridge commutation and full-bridge commutation, are discussed and compared, which shows that the full-bridge commutation could better explore the potential of the back electro-motive forces (EMF), thus can deliver higher efficiency and smaller current ripple. The FOC braking is analyzed with the phasor diagrams. At a given motor speed, the motor turns from the regenerative braking mode into the plug braking mode if the braking torque exceeds a certain limit, which is proportional to the motor speed. Tests in the dynamometer show that a smooth control could be realized by FOC driving control and the highest efficiency and the smallest current ripple could be achieved by FOC braking control, compared to six-step commutation braking control. Therefore, FOC braking is selected as the braking control algorithm for electric vehicles. The proposed research ensures a good motor control performance while maintaining low cost and high

  13. Parameter estimation of an air-bearing suspended test table

    NASA Astrophysics Data System (ADS)

    Fu, Zhenxian; Lin, Yurong; Liu, Yang; Chen, Xinglin; Chen, Fang

    2015-02-01

    A parameter estimation approach is proposed for parameter determination of a 3-axis air-bearing suspended test table. The table is to provide a balanced and frictionless environment for spacecraft ground test. To balance the suspension, the mechanical parameters of the table, including its angular inertias and centroid deviation from its rotating center, have to be determined first. Then sliding masses on the table can be adjusted by stepper motors to relocate the centroid of the table to its rotating center. Using the angular momentum theorem and the coriolis theorem, dynamic equations are derived describing the rotation of the table under the influence of gravity imbalance torque and activating torques. To generate the actuating torques, use of momentum wheels is proposed, whose virtue is that no active control is required to the momentum wheels, which merely have to spin at constant rates, thus avoiding the singularity problem and the difficulty of precisely adjusting the output torques, issues associated with control moment gyros. The gyroscopic torques generated by the momentum wheels, as they are forced by the table to precess, are sufficient to activate the table for parameter estimation. Then least-square estimation is be employed to calculate the desired parameters. The effectiveness of the method is validated by simulation.

  14. Field Test of Room-to-Room Uniformity of Ventilation Air Distribution in Two New Houses

    SciTech Connect

    Hendron, Robert; Anderson, Ren; Barley, Dennis; Rudd, Armin; Townsend, Aaron; Hancock, Ed

    2006-12-01

    This report describes a field test to characterize the uniformity of room-to-room ventilation air distribution under various operating conditions by examining multi-zone tracer gas decay curves and calculating local age-of-air.

  15. Identification of brake wear particles and derivation of a quantitative tracer for brake dust at a major road

    NASA Astrophysics Data System (ADS)

    Gietl, Johanna K.; Lawrence, Roy; Thorpe, Alistair J.; Harrison, Roy M.

    2010-01-01

    Traffic-generated air pollutant emissions can be classified into exhaust and non-exhaust emissions. Increased attention is focussing on non-exhaust emissions as exhaust emissions are progressively limited by regulations. To characterise metal-rich emission from abrasion processes, size-segregated analysis of atmospheric aerosol particles sampled with micro-orifice uniform deposit impactors (MOUDI) in March 2007 in London was performed. The samples were collected at a roadside and a background site and were analysed for Al, Ba, Cu, Fe, Sb, Ti, V, Zn, Ca 2+, K +, Mg 2+, Na +, and NH 4+. Most components showed a clear roadside increment, which was evident as a higher mass concentration and a change in the size distribution. In particular, Fe, Cu, Ba, and Sb correlated highly, indicative of a common traffic-related source. Using complementary information on the fleet composition, vehicle number and average speed, the brake wear emission was calculated using the EMEP/CORINAIR emission database. The total PM 10 and barium emission of the traffic was determined by ratio to NO x whose source strength was estimated from published emission factors. Barium was found to comprise 1.1% of brake wear (PM 10) particles from the traffic fleet as a whole, allowing its use as a quantitative tracer of brake wear emissions at other traffic-influenced sites.

  16. Combination Of Thermography And Pressure Tests To Combat Air Leakage Problems In Building Enclosures

    NASA Astrophysics Data System (ADS)

    Spruin, W. G.

    1987-05-01

    Uncontrolled air leakage in a building enclosure is the main component of space heating and cooling costs. In Atlantic Canada, Public Works Canada has combined thermography and pressure testing to identify design and construction problems in new construction and to identify specific areas of air leakage in existing housing stock. A study case shows how thermography and pressure testing has been utilized to locate and compare specific areas of air leakage in a residence before and after air sealing. The study provides both quantitative and qualitative evidence of how air sealing increases the air tightness in building enclosures.

  17. 49 CFR 393.42 - Brakes required on all wheels.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 5 2010-10-01 2010-10-01 false Brakes required on all wheels. 393.42 Section 393... ACCESSORIES NECESSARY FOR SAFE OPERATION Brakes § 393.42 Brakes required on all wheels. (a) Every commercial motor vehicle shall be equipped with brakes acting on all wheels. (b) Exception. (1) Trucks or...

  18. 49 CFR 570.58 - Electric brake system.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 6 2013-10-01 2013-10-01 false Electric brake system. 570.58 Section 570.58... 10,000 Pounds § 570.58 Electric brake system. (a) Electric brake system integrity. The average brake... manufacturer's maximum current rating. In progressing from zero to maximum, the ammeter indication shall...

  19. 49 CFR 570.58 - Electric brake system.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 6 2014-10-01 2014-10-01 false Electric brake system. 570.58 Section 570.58... 10,000 Pounds § 570.58 Electric brake system. (a) Electric brake system integrity. The average brake... manufacturer's maximum current rating. In progressing from zero to maximum, the ammeter indication shall...

  20. 49 CFR 570.58 - Electric brake system.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 6 2012-10-01 2012-10-01 false Electric brake system. 570.58 Section 570.58... 10,000 Pounds § 570.58 Electric brake system. (a) Electric brake system integrity. The average brake... manufacturer's maximum current rating. In progressing from zero to maximum, the ammeter indication shall...

  1. 49 CFR 570.58 - Electric brake system.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 6 2011-10-01 2011-10-01 false Electric brake system. 570.58 Section 570.58... 10,000 Pounds § 570.58 Electric brake system. (a) Electric brake system integrity. The average brake... manufacturer's maximum current rating. In progressing from zero to maximum, the ammeter indication shall...

  2. 49 CFR 570.58 - Electric brake system.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 6 2010-10-01 2010-10-01 false Electric brake system. 570.58 Section 570.58... 10,000 Pounds § 570.58 Electric brake system. (a) Electric brake system integrity. The average brake... manufacturer's maximum current rating. In progressing from zero to maximum, the ammeter indication shall...

  3. 14 CFR 29.1151 - Rotor brake controls.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Rotor brake controls. 29.1151 Section 29... Rotor brake controls. (a) It must be impossible to apply the rotor brake inadvertently in flight. (b) There must be means to warn the crew if the rotor brake has not been completely released before take-off....

  4. 14 CFR 27.1151 - Rotor brake controls.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Rotor brake controls. 27.1151 Section 27... Rotor brake controls. (a) It must be impossible to apply the rotor brake inadvertently in flight. (b) There must be means to warn the crew if the rotor brake has not been completely released before takeoff....

  5. Diesel Technology: Brakes. Teacher Edition [and] Student Edition.

    ERIC Educational Resources Information Center

    Hilley, Robert; Scarberry, Terry; Kellum, Mary

    This document contains teacher and student materials for a course on brakes in the diesel technology curriculum. The course consists of 12 units organized in three sections. The three units of the introductory section cover: (1) brakes; (2) wheel bearings and seals; and (3) antilock brake systems. The second section, Hydraulic Brakes, contains the…

  6. 49 CFR 393.40 - Required brake systems.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 5 2013-10-01 2013-10-01 false Required brake systems. 393.40 Section 393.40... NECESSARY FOR SAFE OPERATION Brakes § 393.40 Required brake systems. (a) Each commercial motor vehicle must have brakes adequate to stop and hold the vehicle or combination of motor vehicles. Each...

  7. 49 CFR 393.40 - Required brake systems.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 5 2014-10-01 2014-10-01 false Required brake systems. 393.40 Section 393.40... NECESSARY FOR SAFE OPERATION Brakes § 393.40 Required brake systems. (a) Each commercial motor vehicle must have brakes adequate to stop and hold the vehicle or combination of motor vehicles. Each...

  8. 14 CFR 29.1151 - Rotor brake controls.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Rotor brake controls. 29.1151 Section 29... Rotor brake controls. (a) It must be impossible to apply the rotor brake inadvertently in flight. (b) There must be means to warn the crew if the rotor brake has not been completely released before take-off....

  9. 14 CFR 27.1151 - Rotor brake controls.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Rotor brake controls. 27.1151 Section 27... Rotor brake controls. (a) It must be impossible to apply the rotor brake inadvertently in flight. (b) There must be means to warn the crew if the rotor brake has not been completely released before takeoff....

  10. 49 CFR 393.40 - Required brake systems.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 5 2011-10-01 2011-10-01 false Required brake systems. 393.40 Section 393.40... NECESSARY FOR SAFE OPERATION Brakes § 393.40 Required brake systems. (a) Each commercial motor vehicle must have brakes adequate to stop and hold the vehicle or combination of motor vehicles. Each...

  11. 49 CFR 393.40 - Required brake systems.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 5 2012-10-01 2012-10-01 false Required brake systems. 393.40 Section 393.40... NECESSARY FOR SAFE OPERATION Brakes § 393.40 Required brake systems. (a) Each commercial motor vehicle must have brakes adequate to stop and hold the vehicle or combination of motor vehicles. Each...

  12. 14 CFR 29.1151 - Rotor brake controls.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Rotor brake controls. 29.1151 Section 29... Rotor brake controls. (a) It must be impossible to apply the rotor brake inadvertently in flight. (b) There must be means to warn the crew if the rotor brake has not been completely released before take-off....

  13. 49 CFR 393.48 - Brakes to be operative.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 5 2012-10-01 2012-10-01 false Brakes to be operative. 393.48 Section 393.48... NECESSARY FOR SAFE OPERATION Brakes § 393.48 Brakes to be operative. (a) General rule. Except as provided in paragraphs (b), (c), and (d) of this section, all brakes with which a motor vehicle is equipped must at...

  14. 14 CFR 27.1151 - Rotor brake controls.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Rotor brake controls. 27.1151 Section 27... Rotor brake controls. (a) It must be impossible to apply the rotor brake inadvertently in flight. (b) There must be means to warn the crew if the rotor brake has not been completely released before takeoff....

  15. 49 CFR 393.48 - Brakes to be operative.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 5 2014-10-01 2014-10-01 false Brakes to be operative. 393.48 Section 393.48... NECESSARY FOR SAFE OPERATION Brakes § 393.48 Brakes to be operative. (a) General rule. Except as provided in paragraphs (b), (c), and (d) of this section, all brakes with which a motor vehicle is equipped must at...

  16. 14 CFR 29.1151 - Rotor brake controls.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Rotor brake controls. 29.1151 Section 29... Rotor brake controls. (a) It must be impossible to apply the rotor brake inadvertently in flight. (b) There must be means to warn the crew if the rotor brake has not been completely released before take-off....

  17. 14 CFR 27.1151 - Rotor brake controls.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Rotor brake controls. 27.1151 Section 27... Rotor brake controls. (a) It must be impossible to apply the rotor brake inadvertently in flight. (b) There must be means to warn the crew if the rotor brake has not been completely released before takeoff....

  18. 14 CFR 29.1151 - Rotor brake controls.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Rotor brake controls. 29.1151 Section 29... Rotor brake controls. (a) It must be impossible to apply the rotor brake inadvertently in flight. (b) There must be means to warn the crew if the rotor brake has not been completely released before take-off....

  19. 14 CFR 27.1151 - Rotor brake controls.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Rotor brake controls. 27.1151 Section 27... Rotor brake controls. (a) It must be impossible to apply the rotor brake inadvertently in flight. (b) There must be means to warn the crew if the rotor brake has not been completely released before takeoff....

  20. Further experimental studies in wet-brake friction

    SciTech Connect

    Staph, H.E.; Marbach, H.W. Jr.

    1986-01-01

    This paper describes further experimental efforts to determine friction characteristics that define the chatter potential in wet-brake systems as used in tractors and other off-road applications. Changes and improvements to a bench facility described at the 1985 Off-Highway Conference are described. Of particular interest is the decision to examine the very low sliding velocity regime, particularly below 0.34 m/s sliding velocity. Interesting and informative data have been obtained by feeding the input of an accelerometer attached in effect to the caliper brake pads to a frequency analyzer. A spectrum of the energy developed by the vibrating pads over the frequency range of 0 to 250 Hz while the sliding velocity is increased from 0 to 0.85 m/s is obtained. Specifically, the area under the composite frequency curve from 70 to 125 Hz shows good correlation to the chatter propensity of the oil. The results of tests on several oils are described. The ultimate purpose of the research is to provide a relatively rapid screening test for evaluating brake oils for the John Deere-type qualification tests. The overall results emphasize the importance of a low ratio between the breakaway friction and the friction at moderate sliding velocities for low or no chatter.

  1. Design Considerations and Experimental Verification of a Rail Brake Armature Based on Linear Induction Motor Technology

    NASA Astrophysics Data System (ADS)

    Sakamoto, Yasuaki; Kashiwagi, Takayuki; Hasegawa, Hitoshi; Sasakawa, Takashi; Fujii, Nobuo

    This paper describes the design considerations and experimental verification of an LIM rail brake armature. In order to generate power and maximize the braking force density despite the limited area between the armature and the rail and the limited space available for installation, we studied a design method that is suitable for designing an LIM rail brake armature; we considered adoption of a ring winding structure. To examine the validity of the proposed design method, we developed a prototype ring winding armature for the rail brakes and examined its electromagnetic characteristics in a dynamic test system with roller rigs. By repeating various tests, we confirmed that unnecessary magnetic field components, which were expected to be present under high speed running condition or when a ring winding armature was used, were not present. Further, the necessary magnetic field component and braking force attained the desired values. These studies have helped us to develop a basic design method that is suitable for designing the LIM rail brake armatures.

  2. Modeling regenerative braking and storage for vehicles

    SciTech Connect

    Wicks, F.; Donnelly, K.

    1997-12-31

    The fuel savings benefits of regenerative braking and storage for vehicles are often described but not quantified. For example, the federal government and automobile manufacturers are sponsoring a Program for a New Generation of Vehicles (PGNV) with a goal of obtaining a performance of 80 mpg in a family size car. It is typically suggested that such a vehicle will be a hybrid engine and electric drive with regenerative braking. The authors note that while regenerative braking has the potential of saving fuel, it may also do more harm than good as a result of additional weight, less than ideal charge/discharge efficiency on the batteries or storage flywheels and the limited portion of the entire driving cycle when regenerative braking can be utilized. The authors also noted that if regenerative braking can have a net benefit, it would be on a heavy vehicle such as a municipal bus because of the frequent stop and go requirements for both traffic light and passengers. Thus the authors initiated a study of regenerative braking on such a vehicle. The resulting analysis presented in this paper includes data following municipal buses to define the driving cycle, modeling the bus power requirements from weight, aerodynamics and rolling resistance, and then calculating the fuel saving that could result from an ideal regenerative braking system.

  3. Brake wear particle emissions: a review.

    PubMed

    Grigoratos, Theodoros; Martini, Giorgio

    2015-02-01

    Traffic-related sources have been recognized as a significant contributor of particulate matter particularly within major cities. Exhaust and non-exhaust traffic-related sources are estimated to contribute almost equally to traffic-related PM10 emissions. Non-exhaust particles can be generated either from non-exhaust sources such as brake, tyre, clutch and road surface wear or already exist in the form of deposited material at the roadside and become resuspended due to traffic-induced turbulence. Among non-exhaust sources, brake wear can be a significant particulate matter (PM) contributor, particularly within areas with high traffic density and braking frequency. Studies mention that in urban environments, brake wear can contribute up to 55 % by mass to total non-exhaust traffic-related PM10 emissions and up to 21 % by mass to total traffic-related PM10 emissions, while in freeways, this contribution is lower due to lower braking frequency. As exhaust emissions control become stricter, relative contributions of non-exhaust sources-and therefore brake wear-to traffic-related emissions will become more significant and will raise discussions on possible regulatory needs. The aim of the present literature review study is to present the state-of-the-art of the different aspects regarding PM resulting from brake wear and provide all the necessary information in terms of importance, physicochemical characteristics, emission factors and possible health effects. PMID:25318420

  4. A global strategy based on experiments and simulations for squeal prediction on industrial railway brakes

    NASA Astrophysics Data System (ADS)

    Sinou, J.-J.; Loyer, A.; Chiello, O.; Mogenier, G.; Lorang, X.; Cocheteux, F.; Bellaj, S.

    2013-09-01

    This paper presents an overview of recent experimental and numerical investigations on industrial railway brakes. The goal of the present study is to discuss the relevance of the mechanical modeling strategy for squeal prediction. Specific experimental set-ups based on transient and controlled braking tests are designed for this purpose. Measurements are performed on it to investigate the dynamic behavior of TGV squeal noise and its squeal characterization through experiments. It will be demonstrated that it is possible to build consistent and efficient finite element models to simulate squeal events in TGV brake systems. The numerical strategy will be presented, including not only the modeling of the TGV brake system and the stability analysis, but also the transient nonlinear dynamic and computational process based on efficient reduced basis. This complete numerical strategy allows us to perform relevance squeal prediction on industrial railway brakes. This study comes within the scope of a research program AcouFren that is supported by ADEME (Agence De l'Environnement et de la Maîtrise de l'Energie) concerning the reduction of the squeal noise generated by high power railway disc brakes. experiments with an evolution of the rotational speed of the disc: these tests are called "transient braking tests" and correspond to real braking tests, experiments with a controlled steady rotational speed (i.e. dynamic fluctuations in rotational speed are not significant): these tests are called "controlled braking tests". In the present study, the Continuous Wavelet Transform (CWT) [20] is used to study the time-history responses of the TGV brake system. So, a brief basic theory of the wavelet analysis that transforms a signal into wavelets that are well localized both in frequency and time is presented in this part of the paper. Considering a function f(t), the associated Continuous Wavelet Transform (CWT) corresponds to a wavelet transform given by W(a,b

  5. Recycled brake linings as partial aggregate substitute in asphalt paving. Construction and final report. Report for July 1992-August 1996

    SciTech Connect

    Miller, P.A.; Sukley, R.

    1996-09-01

    The purpose of this project was to evaluate the performance of asphalt containing various percentages of brake lining as an aggregate, and compare its performance to that of normal asphalt containing natural aggregate. This project is an effort to explore alternate ways to use waste product. Four test section of FB-2 Modified mix containing brake lining materials were placed in July 1992 along with one control section on SR 3022 in Mercer county. To date all sections are performing satisfactory, and Brake linings should be recommended as a viable partial replacement of aggregate in bituminous materials. This study only considered the performance of only off-spec brake linings, therefore, any performance data or enviromental effects of placement of used brake material should be addressed.

  6. Operational test report for 241-AW tank inlet air control stations

    SciTech Connect

    Minteer, D.J., Westinghouse Hanford

    1996-07-03

    This document reports the results of operational testing on tank inlet air control stations in 241-AW tank farm. An air control station was installed on each of the six AW tanks. Operational testing consisted of a simple functional test of each station`s air flow controller, aerosol testing of each station`s HEPA filter, and final ventilation system balancing (i.e., tank airflows and vacuum level) using the air control stations. The test was successful and the units were subsequently placed into operation.

  7. Wear studies on aircraft brake materials

    NASA Technical Reports Server (NTRS)

    Ho, T. L.

    1977-01-01

    An investigation of both worn surfaces of friction pads and steel rotors which are being applied in current aircraft brakes has been carried out by employing an X-ray diffraction technique. It consists of the analysis of chemical element distribution in the surface layers. The wear particles were also examined by using the scanning electron microscope. The initiation and growth of surface cracks and the oxidation were emphasized in this investigation. A wear model was proposed for the current aircraft brake materials. Essentially this model proposed that cracks are formed in the surface layer of the brake material due to the normal and frictional stresses. It is primarily surface temperature dependent.

  8. Screw-released roller brake

    NASA Technical Reports Server (NTRS)

    Vranish, John M. (Inventor)

    1999-01-01

    A screw-released roller brake including an input drive assembly, an output drive assembly, a plurality of locking sprags, a mechanical tripper nut for unlocking the sprags, and a casing therefor. The sprags consist of three dimensional (3-D) sprag members having pairs of contact surface regions which engage respective pairs of contact surface regions included in angular grooves or slots formed in the casing and the output drive assembly. The sprags operate to lock the output drive assembly to the casing to prevent rotation thereof in an idle mode of operation. In a drive mode of operation, the tripper is either self actuated or motor driven and is translated linearly up and down against a spline and at the limit of its travel rotates the sprags which unlock while coupling the input drive assembly to the output drive assembly so as to impart a turning motion thereto in either a clockwise or counterclockwise direction.

  9. Heat generation in aircraft tires under braked rolling conditions

    NASA Technical Reports Server (NTRS)

    Clark, S. K.; Dodge, R. N.

    1984-01-01

    An analytical model was developed to approximate the internal temperature distribution in an aircraft tire operating under conditions of unyawed braked rolling. The model employs an array of elements to represent the tire cross section and considers the heat generated within the tire to be caused by the change in strain energy associated with cyclic tire deflection. The additional heating due to tire slip and stresses induced by braking are superimposed on the previously developed free rolling model. An extensive experimental program was conducted to verify temperatures predicted from the analytical model. Data from these tests were compared with calculations over a range of operating conditions. The model results were in reasonably good agreement with measured values.

  10. 75 FR 57393 - Parts and Accessories Necessary for Safe Operation: Antilock Brake Systems

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-21

    ..., 2008, issue of the Federal Register (73 FR 3316). II. Abbreviations ABS Anti-lock Braking Systems CMV... Safety Standard FR Federal Register FHWA Federal Highway Administration NHTSA National Highway Traffic... Federal Register (on March 10, 1995 60 FR 13216). As amended by that final rule, FMVSS No. 121, Air...

  11. Air pollution control system testing at the DOE offgas components test facility

    SciTech Connect

    Burns, D.B.; Speed, D.; VanPelt, W.; Burns, H.H.

    1997-06-01

    In 1997, the Department of Energy (DOE) Savannah River Site (SRS) plans to begin operation of the Consolidated Incineration Facility (CIF) to treat solid and liquid RCRA hazardous and mixed wastes. The Savannah River Technology Center (SRTC) leads an extensive technical support program designed to obtain incinerator and air pollution control equipment performance data to support facility start-up and operation. A key component of this technical support program includes the Offgas Components Test Facility (OCTF), a pilot-scale offgas system test bed. The primary goal for this test facility is to demonstrate and evaluate the performance of the planned CIF Air Pollution Control System (APCS). To accomplish this task, the OCTF has been equipped with a 1/10 scale CIF offgas system equipment components and instrumentation. In addition, the OCTF design maximizes the flexibility of APCS operation and facility instrumentation and sampling capabilities permit accurate characterization of all process streams throughout the facility. This allows APCS equipment performance to be evaluated in an integrated system under a wide range of possible operating conditions. This paper summarizes the use of this DOE test facility to successfully demonstrate APCS operability and maintainability, evaluate and optimize equipment and instrument performance, and provide direct CIF start-up support. These types of facilities are needed to permit resolution of technical issues associated with design and operation of systems that treat and dispose combustible hazardous, mixed, and low-level radioactive waste throughout and DOE complex.

  12. Technology Solutions Case Study: Ventilation System Effectiveness and Tested Indoor Air Quality Impacts

    SciTech Connect

    A. Rudd and D. Bergey

    2015-08-01

    Ventilation system effectiveness testing was conducted at two unoccupied, single-family, detached lab homes at the University of Texas - Tyler. Five ventilation system tests were conducted with various whole-building ventilation systems. Multizone fan pressurization testing characterized building and zone enclosure leakage. PFT testing showed multizone air change rates and interzonal airflow filtration. Indoor air recirculation by a central air distribution system can help improve the exhaust ventilation system by way of air mixing and filtration. In contrast, the supply and balanced ventilation systems showed that there is a significant benefit to drawing outside air from a known outside location, and filtering and distributing that air. Compared to the Exhaust systems, the CFIS and ERV systems showed better ventilation air distribution and lower concentrations of particulates, formaldehyde and other VOCs.

  13. Test/QA Plan (TQAP) for Verification of Semi-Continuous Ambient Air Monitoring Systems

    EPA Science Inventory

    The purpose of the semi-continuous ambient air monitoring technology (or MARGA) test and quality assurance plan is to specify procedures for a verification test applicable to commercial semi-continuous ambient air monitoring technologies. The purpose of the verification test is ...

  14. Optimal design and selection of magneto-rheological brake types based on braking torque and mass

    NASA Astrophysics Data System (ADS)

    Nguyen, Q. H.; Lang, V. T.; Choi, S. B.

    2015-06-01

    In developing magnetorheological brakes (MRBs), it is well known that the braking torque and the mass of the MRBs are important factors that should be considered in the product’s design. This research focuses on the optimal design of different types of MRBs, from which we identify an optimal selection of MRB types, considering braking torque and mass. In the optimization, common types of MRBs such as disc-type, drum-type, hybrid-type, and T-shape types are considered. The optimization problem is to find an optimal MRB structure that can produce the required braking torque while minimizing its mass. After a brief description of the configuration of the MRBs, the MRBs’ braking torque is derived based on the Herschel-Bulkley rheological model of the magnetorheological fluid. Then, the optimal designs of the MRBs are analyzed. The optimization objective is to minimize the mass of the brake while the braking torque is constrained to be greater than a required value. In addition, the power consumption of the MRBs is also considered as a reference parameter in the optimization. A finite element analysis integrated with an optimization tool is used to obtain optimal solutions for the MRBs. Optimal solutions of MRBs with different required braking torque values are obtained based on the proposed optimization procedure. From the results, we discuss the optimal selection of MRB types, considering braking torque and mass.

  15. Regenerative braking strategies, vehicle safety and stability control systems: critical use-case proposals

    NASA Astrophysics Data System (ADS)

    Oleksowicz, Selim A.; Burnham, Keith J.; Southgate, Adam; McCoy, Chris; Waite, Gary; Hardwick, Graham; Harrington, Cian; McMurran, Ross

    2013-05-01

    The sustainable development of vehicle propulsion systems that have mainly focused on reduction of fuel consumption (i.e. CO2 emission) has led, not only to the development of systems connected with combustion processes but also to legislation and testing procedures. In recent years, the low carbon policy has made hybrid vehicles and fully electric vehicles (H/EVs) popular. The main virtue of these propulsion systems is their ability to restore some of the expended energy from kinetic movement, e.g. the braking process. Consequently new research and testing methods for H/EVs are currently being developed. This especially concerns the critical 'use-cases' for functionality tests within dynamic events for both virtual simulations, as well as real-time road tests. The use-case for conventional vehicles for numerical simulations and road tests are well established. However, the wide variety of tests and their great number (close to a thousand) creates a need for selection, in the first place, and the creation of critical use-cases suitable for testing H/EVs in both virtual and real-world environments. It is known that a marginal improvement in the regenerative braking ratio can significantly improve the vehicle range and, therefore, the economic cost of its operation. In modern vehicles, vehicle dynamics control systems play the principal role in safety, comfort and economic operation. Unfortunately, however, the existing standard road test scenarios are insufficient for H/EVs. Sector knowledge suggests that there are currently no agreed tests scenarios to fully investigate the effects of brake blending between conventional and regenerative braking as well as the regenerative braking interaction with active driving safety systems (ADSS). The paper presents seven manoeuvres, which are considered to be suitable and highly informative for the development and examination of H/EVs with regenerative braking capability. The critical manoeuvres presented are considered to be

  16. Effect of frictional heating on brake materials

    NASA Technical Reports Server (NTRS)

    Ho, T.-L.; Peterson, M. B.; Ling, F. F.

    1974-01-01

    An exploratory study of the properties of aircraft brake materials was made to determine ways of improving friction and wear behavior while minimizing surface temperatures. It is found that frictional variation at high temperature involves material softening and metal transfer, formation of oxides, and surface melting. The choice of proper materials to combat these effects is discussed. Minimum surface temperatures are found to result from use of materials with large density-specific heat and density-specific heat-conductivity factors, use of a higher load-lower friction system, and maximization of the contact area. Some useful trade-off criteria for the size of brake disks against weight considerations are suggested. Additional information on material behavior and peak braking temperatures was gathered from an inspection of used brake pads and rotor disks.

  17. 49 CFR 229.46 - Brakes: general.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ..., DEPARTMENT OF TRANSPORTATION RAILROAD LOCOMOTIVE SAFETY STANDARDS Safety Requirements Brake System § 229.46... placing such a locomotive in trailing position adequately isolates the non-functional valves so as...

  18. Energy use test facility: CAC-DOE solar air heater test report

    NASA Astrophysics Data System (ADS)

    1981-11-01

    The solar air heater testing demonstrated an attractive application for residential space heating, especially appealing to the do-it-yourself market. Simple improvements in construction, such as caulking of the glazing, could increase collector performance at little cost. The operating cost of the fan was insignificant, being less than $0.05/week. Tested in its as-shipped configuration at 96.1 cfm (3 cfm/ft (2)), the useful energy delivered averaged 20,000 Btu/day for six days in December. The electrical consumption of the fan was approximately 1 kWh. Doubling the flowrate did not increase collector performance appreciably. A TRNSYS computer simulation model for this solar air heater design was validated by comparing the measured test data on Jaunary 4, 1981 with calculated values. TRNSYS predicted that measured collector outlet temperatures within +- 1.20F and the energy delivered within +- 3%. The excellent agreement was obtained by adjusting the collector loss coefficient to an unrealistically low value; therefore, a parametric study is recommended to determine the model sensitivity to varying different parameters. A first-order collector efficiency curve was derived from the TRNSYS simulations which compared well with the curve defined by the clear-day measured data.

  19. Method and apparatus for wind turbine braking

    DOEpatents

    Barbu, Corneliu; Teichmann, Ralph; Avagliano, Aaron; Kammer, Leonardo Cesar; Pierce, Kirk Gee; Pesetsky, David Samuel; Gauchel, Peter

    2009-02-10

    A method for braking a wind turbine including at least one rotor blade coupled to a rotor. The method includes selectively controlling an angle of pitch of the at least one rotor blade with respect to a wind direction based on a design parameter of a component of the wind turbine to facilitate reducing a force induced into the wind turbine component as a result of braking.

  20. Oscillatory flow braking: inner magnetosphere observations

    NASA Astrophysics Data System (ADS)

    Panov, E. V.; Nakamura, R.; Baumjohann, W.; Angelopoulos, V.

    2013-12-01

    We search for damped oscillatory flow braking events observed by THEMIS/ARTEMIS in the near-Earth plasma sheet when their counterpart in the inner magnetosphere was observed. By comparing the particle and magnetic field data in the two locations we analyze the feedback of the inner magnetosphere to plasma sheet oscillatory flow braking. We discuss the possible role of the oscillatory flow events for plasma injection into the inner magnetosphere.

  1. Power-Factor Controller With Regenerative Braking

    NASA Technical Reports Server (NTRS)

    Nola, F. J.

    1982-01-01

    Modified power-factor motor-control circuit operates motor as a phase-controlled generator when load attempts to turn at higher than synchronous speed. An induction motor is required to act at times as a brake. Circuit modification allows power-factor controller to save energy in motoring mode and convert automatically to an induction-generator controller in generating, or braking, mode.

  2. Automated visual inspection of brake shoe wear

    NASA Astrophysics Data System (ADS)

    Lu, Shengfang; Liu, Zhen; Nan, Guo; Zhang, Guangjun

    2015-10-01

    With the rapid development of high-speed railway, the automated fault inspection is necessary to ensure train's operation safety. Visual technology is paid more attention in trouble detection and maintenance. For a linear CCD camera, Image alignment is the first step in fault detection. To increase the speed of image processing, an improved scale invariant feature transform (SIFT) method is presented. The image is divided into multiple levels of different resolution. Then, we do not stop to extract the feature from the lowest resolution to the highest level until we get sufficient SIFT key points. At that level, the image is registered and aligned quickly. In the stage of inspection, we devote our efforts to finding the trouble of brake shoe, which is one of the key components in brake system on electrical multiple units train (EMU). Its pre-warning on wear limitation is very important in fault detection. In this paper, we propose an automatic inspection approach to detect the fault of brake shoe. Firstly, we use multi-resolution pyramid template matching technology to fast locate the brake shoe. Then, we employ Hough transform to detect the circles of bolts in brake region. Due to the rigid characteristic of structure, we can identify whether the brake shoe has a fault. The experiments demonstrate that the way we propose has a good performance, and can meet the need of practical applications.

  3. VERIFICATION TESTING OF AIR POLLUTION CONTROL TECHNOLOGY QUALITY MANAGEMENT PLAN

    EPA Science Inventory

    This document is the basis for quality assurance for the Air Pollution Control Technology Verification Center (APCT Center) operated under the U.S. Environmental Protection Agency (EPA). It describes the policies, organizational structure, responsibilities, procedures, and qualit...

  4. Energy Efficiency in Heavy Vehicle Tires, Drivetrains, and Braking Systems

    SciTech Connect

    Peter J. Blau

    2000-04-26

    This document was prepared to support the primary goals of the Department of Energy, Office of Heavy Vehicle Technologies. These were recently stated as follows: ''Develop by 2004 the enabling technologies for a class 7-8 truck with a fuel efficiency of 10 mpg (at 65 mph) which will meet prevailing emission standards. For Class 3-6 trucks operating on an urban driving cycle, develop by 2004 commercially viable vehicles that achieve at least double the fuel economy of comparable current vehicles (1999), and as a research goal, reduce criteria pollutants to 30% below EPA standards. Develop by 2004 the diesel engine enabling technologies to support large-scale industry dieselization of Class 1 and 2 trucks, achieving a 35 % fuel efficiency improvement over comparable gasoline-fueled trucks, while meeting applicable emissions standards.'' The enabling technologies for improving the fuel efficiency of trucks, include not only engine technologies but also technologies involved with lowering the rolling resistance of tires, reducing vehicle aerodynamic drag, improving thermal management, and reducing parasitic frictional losses in drive train components. Opportunities also exist for making better use of the energy that might ordinarily be dissipated during vehicle braking. Braking systems must be included in this evaluation since safety in truck operations is vital, and braking requirements are greater for vehicles having lowered resistance to rolling. The Office of Heavy Vehicle Technologies has initiated a program to improve the aerodynamics of heavy vehicles through wind tunnel testing, computational modeling, and on-road evaluations. That activity is described in a separate multi-year plan; therefore, emphasis in this document will be on tires, drive trains, and braking systems. Recent, dramatic fluctuations in diesel fuel prices have emphasized the importance of effecting savings in truck fuel economy by implementing new component designs and materials.

  5. Laboratory testing during critical care transport: point-of-care testing in air ambulances.

    PubMed

    Di Serio, Francesca; Petronelli, Maria Antonia; Sammartino, Eugenio

    2010-07-01

    Air and ground transport are used for prehospital transport of patients in acute life-threatening situations, and increasingly, critically ill patients undergo interhospital transportation. Results from clinical studies suggest that critical tests performed during the transport of critically ill patients presents a potential opportunity to improve patient care. Our project was to identify, according to the recommendations published at this time, a model of point-of-care testing (POCT) (arterial blood gases analysis and glucose, sodium, potassium, ionized calcium, hematocrit/hemoglobin measurements) in air ambulances. In order to identify the key internal and external factors that are important to achieving our objective, an analysis of the Strengths, Weaknesses, Opportunities, and Threats (SWOT analysis) was incorporated into our planning model prior to starting the project. To allow the entire POCT process (pre-, intra-, and post-analytic steps) to be under the control of the reference laboratory, an experimental model of information technology was applied. Real-time results during transport of critically ill patients must be considered to be an integral part of the patient care process and excellent channels of communication are needed between the intensive care units, emergency medical services and laboratories. With technological and computer advances, POCT during critical care transport will certainly increase in the future: this will be a challenge from a laboratory and clinical context. PMID:20406127

  6. DFS Dive-control Brakes for Gliders and Airplanes ; And, Analytical Study of the Drag of the DFS Dive-control Brake

    NASA Technical Reports Server (NTRS)

    Jacobs, Hans; Wanner, Adolf

    1940-01-01

    These two reports are surveys on the progress and present state of development of dive-control flaps for gliders and airplanes. The second article describes how on the basis of wind tunnel and free-flight tests, the drag increase on brake flaps of the type DFS, can be predicted. Pressure records confirm a two-dimensional load distribution along the brake-flap surface Aerodynamically, the location of the brake flaps along the span is of importance for reasons of avoidance of vibration and oscillation phenomena on control and tail surfaces; statically, because of the magnitude of the frontal drag in diving with respect to the bending moments, which may become decisive for the dimensions of the wing attachment and for the wing covering.

  7. 40 CFR 86.161-00 - Air conditioning environmental test facility ambient requirements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... to simulate the impact of an ambient heat load on the power requirements of the vehicle's air... elements that are discussed are ambient air temperature and humidity, minimum test cell size, solar heating... be shown that all of the ambient test condition performance requirements are satisfied. (d)...

  8. 40 CFR 86.161-00 - Air conditioning environmental test facility ambient requirements.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... to simulate the impact of an ambient heat load on the power requirements of the vehicle's air... elements that are discussed are ambient air temperature and humidity, minimum test cell size, solar heating... be shown that all of the ambient test condition performance requirements are satisfied. (d)...

  9. 40 CFR 86.162-03 - Approval of alternative air conditioning test simulations.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... conditioning test simulations. 86.162-03 Section 86.162-03 Protection of Environment ENVIRONMENTAL PROTECTION... alternative air conditioning test simulations. (a) Upon petition from a manufacturer or upon the Agency's own initiative, the Administrator will approve a simulation of the environmental cell for air conditioning...

  10. Building America Top Innovations 2014 Profile: HVAC Cabinet Air Leakage Test Method

    SciTech Connect

    none,

    2014-11-01

    This 2014 Top Innovation profile describes Building America-funded research by teams and national laboratories that resulted in the development of an ASHRAE standard and a standardized testing method for testing the air leakage of HVAC air handlers and furnace cabinets and has spurred equipment manufacturers to tighten the cabinets they use for residential HVAC systems.

  11. 40 CFR 86.162-03 - Approval of alternative air conditioning test simulations.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... initiative, the Administrator will approve a simulation of the environmental cell for air conditioning test... environmental cell test data for the range of vehicles to be covered by the simulation including items such as the tailpipe emissions, air conditioning compressor load, and fuel economy. (2) For any...

  12. Functional performance testing of the universal super absorbing air filters FSU 70 „Air by Corneliu”

    NASA Astrophysics Data System (ADS)

    Raţiu, S.; Birtok-Băneasă, C.; Alexa, V.; Kiss, I.

    2015-06-01

    This paper presents the experimental methodology to carry out functional performance tests for an air filter with a particular design of its housing, generically named Universal super absorbing FSU 70 „Air by Corneliu”. The tests were carried out in the Internal Combustion Engines Laboratory, within the specialization "Road automotives" belonging to the Faculty of Engineering Hunedoara, component of “Politehnica” University of Timisoara. We present some comparative values of various operating parameters of the engine fitted, in the first measuring session, with the original filter, and then with the studied filter.

  13. Electromagnetic brake/clutch device

    NASA Technical Reports Server (NTRS)

    Vranish, John M. (Inventor)

    1994-01-01

    An electromagnetic brake/clutch device includes a drive shaft supported by at least one bearing for transmitting torque, a housing, affixed to prevent its rotation, surrounding the drive shaft, and an electromagnetically activated device within the housing to selectively prevent and allow rotation of the drive shaft. The electromagnetically activated device includes a plurality of cammed rollers to prevent counter-clockwise rotation of the drive shaft. The drive shaft includes a circumferential disk and the housing includes a reaction ring for engagement with the plurality of cammed rollers. The plurality of cammed rollers are released from engagement with the circumferential disk and the reaction ring by a plurality of tripping mechanisms within the housing. The tripping action uses the locking force to act as a release force merely by changing the boundary conditions of the roller interface angles. The tripping mechanisms include trippers for disengaging the plurality of cammed rollers and an anvil shaped portion for providing lateral movement of the trippers. The plurality of cammed rollers is preloaded to engagement with the circumferential disk and reaction ring by a spring, and is located with respect to an adjacent tripping mechanism with another spring.

  14. Braking Index of Isolated Pulsars

    NASA Astrophysics Data System (ADS)

    Hamil, Oliver; Stone, Jirina; Urbanec, Martin; Urbancova, Gabriela

    2015-04-01

    Isolated pulsars are rotating neutron stars with accurately measured angular velocities Ω, and their time derivatives which show unambiguously that the pulsars are slowing down. The exact mechanism of the spin-down is a question of debate in detail, but the commonly accepted view is that it arises through emission of magnetic dipole radiation (MDR). The energy loss by a rotating pulsar is proportional to a model dependent power of Ω. This relation leads to the power law Ω˙ = -K Ωn where n is called the braking index, equal to the ratio (ΩΩ̈)/ Ω˙2 . The simple MDR model predicts the value of n = 3, but observations of isolated pulsars provide rather precise values of n, individually accurate to a few percent or better, in the range 1 < n < 2.8, which is consistently less than the predictions of the MDR model. In this work, we study the dynamical limits of the MDR model as a function of angular velocity. The effects of variation in the rest mass, the moment of inertia, and the dependence on a realistic Equation of State of the rotating star are considered. Furthermore, we introduce a simulated superfluid effect by which the angular momentum of the core is eliminated from the calculation.

  15. Thermal Gradient Behavior of TBCs Subjected to a Laser Gradient Test Rig: Simulating an Air-to-Air Combat Flight

    NASA Astrophysics Data System (ADS)

    Lima, Rogerio S.; Marple, Basil R.; Marcoux, P.

    2016-01-01

    A computer-controlled laser test rig (using a CO2 laser) offers an interesting alternative to traditional flame-based thermal gradient rigs in evaluating thermal barrier coatings (TBCs). The temperature gradient between the top and back surfaces of a TBC system can be controlled based on the laser power and a forced air back-face cooling system, enabling the temperature history of complete aircraft missions to be simulated. An air plasma spray-deposited TBC was tested and, based on experimental data available in the literature, the temperature gradients across the TBC system (ZrO2-Y2O3 YSZ top coat/CoNiCrAlY bond coat/Inconel 625 substrate) and their respective frequencies during air-to-air combat missions of fighter jets were replicated. The missions included (i) idle/taxi on the runway, (ii) take-off and climbing, (iii) cruise trajectory to rendezvous zone, (iv) air-to-air combat maneuvering, (v) cruise trajectory back to runway, and (vi) idle/taxi after landing. The results show that the TBC thermal gradient experimental data in turbine engines can be replicated in the laser gradient rig, leading to an important tool to better engineer TBCs.

  16. Adaptive controller for regenerative and friction braking system

    DOEpatents

    Davis, Roy I.

    1990-01-01

    A regenerative and friction braking system for a vehicle having one or more roadwheels driven by an electric traction motor includes a driver responsive device for producing a brake demand signal having a magnitude corresponding to the level of braking force selected by the driver and friction and regenerative brakes operatively connected with the roadwheels of the vehicle. A system according to this invention further includes control means for operating the friction and regenerative braking subsystems so that maximum brake torques sustainable by the roadwheels of the vehicle without skidding or slipping will not be exceeded.

  17. Adaptive controller for regenerative and friction braking system

    DOEpatents

    Davis, R.I.

    1990-10-16

    A regenerative and friction braking system for a vehicle having one or more road wheels driven by an electric traction motor includes a driver responsive device for producing a brake demand signal having a magnitude corresponding to the level of braking force selected by the driver and friction and regenerative brakes operatively connected with the road wheels of the vehicle. A system according to this invention further includes control means for operating the friction and regenerative braking subsystems so that maximum brake torques sustainable by the road wheels of the vehicle without skidding or slipping will not be exceeded. 8 figs.

  18. Performance of a fully mechanical parking brake system for passenger cars

    NASA Astrophysics Data System (ADS)

    Rozaini, A. H.; Ishak, M. R.; Abu Bakar, A. R.; Mohd Zain, M. Z.

    2013-12-01

    In order to ensure that a vehicle remains stationary when it is parked at a certain road slope, the driver has to apply sufficient pulling force on the handbrake lever. Otherwise, the vehicle will start to rollaway where the torque generated by the parking brake system is lower that the torque required by the vehicle to remain stationary. This poses a danger situation not only to the vehicle's occupants but also to the people surrounding it. Thus, this paper aims to investigate performance of a typical parking brake system used in passenger cars. A theoretical model of drum-type parking brake system is derived and later being validated by test data that measured from the parking brake test bench. A good agreement is achieved between calculated and test results. Results from the model show that the parking brake system used in this work can hold the vehicle stationary at 11 degree slope less than 200 N of the applied force and thus it meets the regulation requirement, and also the vehicle will not rollaway even though there are four adult passengers inside it.

  19. Comparison of Tests on Air Propellers in Flight with Wind Tunnel Model Tests on Similar Forms

    NASA Technical Reports Server (NTRS)

    Durand, W F; Lesley, E P

    1926-01-01

    The purpose of this investigation was to determine the performance, characteristics, and coefficients of full-sized air propellers in flight and to compare these results with those derived from wind-tunnel tests on reduced scale models of similar geometrical form. The full-scale equipment comprised five propellers in combination with a VE-7 airplane and Wright E-4 engine. This part of the work was carried out at the Langley Memorial Aeronautical Laboratory, between May 1 and August 24, 1924, and was under the immediate charge of Mr. Lesley. The model or wind-tunnel part of the investigation was carried out at the Aerodynamic Laboratory of Stanford University and was under the immediate charge of Doctor Durand. A comparison of the curves for full-scale results with those derived from the model tests shows that while the efficiencies realized in flight are close to those derived from model tests, both thrust developed and power absorbed in flight are from 6 to 10 per cent greater than would be expected from the results of model tests.

  20. Environmental Technology Verification: Supplement to Test/QA Plan for Biological and Aerosol Testing of General Ventilation Air Cleaners; Bioaerosol Inactivation Efficiency by HVAC In-Duct Ultraviolet Light Air Cleaners

    EPA Science Inventory

    The Air Pollution Control Technology Verification Center has selected general ventilation air cleaners as a technology area. The Generic Verification Protocol for Biological and Aerosol Testing of General Ventilation Air Cleaners is on the Environmental Technology Verification we...

  1. Relationship between Air Force Officer Qualifying Test Scores and Success in Air Weapons Controller Training. Interim Report for the Period November 1982-February 1984.

    ERIC Educational Resources Information Center

    Finegold, Lawrence S.; Rogers, Deborah

    This project investigated the relationship between Air Force Officer Qualifying Test (AFOQT) composite scores and student performance in Air Force air weapons controller training. The purpose of this study was to examine the feasibility of using AFOQT scores as one selection criteria for entry to the air weapons controller field. An analysis of…

  2. Laboratory Testing of Aerosol for Enclosure Air Sealing

    SciTech Connect

    Harrington, Curtis; Modera, Mark

    2012-05-01

    This report presents a process for improving the air tightness of a building envelope by sealing shell leaks with an aerosol sealing technology. Both retrofit and new construction applications are possible through applying this process either in attics and crawlspaces or during rough-in stage.

  3. A new guide for commissioning air handling systems: Using a model functional test

    SciTech Connect

    Haasl, Tudi; Sellers, David; Friedman, Hannah; Piette, Mary Ann; Bourassa, Norman; Gillespie, Ken

    2002-05-01

    Functional tests are a set of detailed instructions for building commissioning that demand extensive HVAC system knowledge to write and perform. Understanding the energy use implications and theory behind the test procedures, estimating the costs and benefits of doing a particular test, implementing the tests correctly, and resolving problems require years of field experience. As part of a large research project now underway, a practical guide is being developed that communicates this knowledge. This paper presents the components and intended use of the Functional Testing Guide and Model Functional Test for Air Handling Systems. A series of model functional tests, starting at the outdoor air intake section and proceeding through the air handling unit, distribution system, and terminal equipment and ending at the exhaust air discharge point, are provided for many commonly installed air handling system configurations. The model functional tests contain advice for tailoring the test procedures to specific system configurations, desirable and undesirable testing outcomes, a calculation appendix, references to other resources, and examples of completed test forms. The guide is an educational resource, with background information that clarifies the principles behind testing configurations and results. The functional tests have been selected from an extensive commissioning test protocol library compiled by Pacific Gas and Electric in 2001. The guide also includes a design guideline for the selection of control and monitoring points and a design intent documentation form.

  4. An Experimental Investigation of the Effect of Propellers Used as Aerodynamic Brakes on Stability and Control

    NASA Technical Reports Server (NTRS)

    Hanson, Frederick H

    1945-01-01

    Tests were made of a model representative of a single-engine tractor-type airplane for the purpose of determining the stability and control effects of a propeller used as an aerodynamic brake. The tests were made with single-and dual-rotation propellers to show the effect of type of propeller rotation, and with positive thrust to provide basic data with which to compare the effects of negative thrust. Four configurations of the model were used to give the effects of tilting the propeller thrust axis down 5 deg., raising the horizontal tail, and combining both tilt and raised tail. Results of the tests are reported herein. The effects of negative thrust were found to be significant. The longitudinal stability was increased because of the loss of wing lift and increase of the angle of attack of the tail. Directional stability and both longitudinal and directional control were decreased because of the reduced velocity at the tail. These effects are moderate for moderate braking but become pronounced with full-power braking, particularly at high values of lift coefficient. The effects of model configuration changes were small when compared with the over-all effects of negative-thrust operation; however, improved stability and control characteristics were exhibited by the model with the tilted thrust axis. Raising the horizontal tail improved the longitudinal characteristics, but was detrimental to directional characteristics. The use of dual-rotation propeller reduced the directional trim charges resulting from the braking operation. A prototype airplane was assumed and handling qualities were computed and analyzed for normal (positive thrust) and braking operation with full and partial power. The results of these analyses are presented for the longitudinal characteristics in steady and accelerated flight, and for the directional characteristics in high- and low-speed flight. It was found that by limiting the power output of the engine (assuming the constant

  5. Influence of friction drive lift gears construction on the length of braking distance

    NASA Astrophysics Data System (ADS)

    Lonkwic, Poul

    2015-03-01

    The friction drive elevators the influence of the braking distance has very high significance to meet certain safety regulations and comfort. During the emergency braking the delay for the system a frame and a cabin should be within the range from 0.2 to 9.81 m/s2. However, there are no specialist literatures regarding the issues connected with emergency braking of elevating devices either. The results of the own empirical research work are presented regarding the influence of design changes on the working parameters of the friction drive elevator gears. ASG100, KB160, PP16, PR2000UD and CHP2000 types of safety progressive gears are analyzed. ASG100, KB160, PP16, PR2000UD type progressive gears are already produced by European manufacturers. CHP2000 type gears are established as the alternative option for the already existing solutions. The unique cam system has been used in the CHP 2000 gears. The cam leverage gives the chance to unblock, in a very easy way, the clamed gears after braking. Thus, it is a key aspect to perform laboratory tests over the braking process of a newly created solution. The proper value of the braking distance has a significant influence on the value of delay in terms of binding standards. The influence of loading on the effective braking distance and the value of the falling elevator cabin speed are analyzed and the results are presented. The results presented are interesting from lift devices operation and a new model of CHP 2000 progressive gear point of view.

  6. Laboratory Testing of Aerosol for Enclosure Air Sealing

    SciTech Connect

    Harrington, C.; Modera, M.

    2012-05-01

    Space conditioning energy use can be significantly reduced by addressing uncontrolled infiltration and exfiltration through the envelope of a building. A process for improving the air tightness of a building envelope by sealing shell leaks with an aerosol sealing technology is presented. Both retrofit and new construction applications are possible through applying this process either in attics and crawlspaces or during rough-in stage.

  7. Effect of air-entry angle on performance of a 2-stroke-cycle compression-ignition engine

    NASA Technical Reports Server (NTRS)

    Earle, Sherod L; Dutee, Francis J

    1937-01-01

    An investigation was made to determine the effect of variations in the horizontal and vertical air-entry angles on the performance characteristics of a single-cylinder 2-stroke-cycle compression-ignition test engine. Performance data were obtained over a wide range of engine speed, scavenging pressure, fuel quantity, and injection advance angle with the optimum guide vanes. Friction and blower-power curves are included for calculating the indicated and net performances. The optimum horizontal air-entry angle was found to be 60 degrees from the radial and the optimum vertical angle to be zero, under which conditions a maximum power output of 77 gross brake horsepower for a specific fuel consumption of 0.52 pound per brake horsepower-hour was obtained at 1,800 r.p.m. and 16-1/2 inches of Hg scavenging pressure. The corresponding specific output was 0.65 gross brake horsepower per cubic inch of piston displacement. Tests revealed that the optimum scavenging pressure increased linearly with engine speed. The brake mean effective pressure increased uniformly with air quantity per cycle for any given vane angle and was independent of engine speed and scavenging pressure.

  8. DEVELOPING A FRAMEWORK FOR TESTING INDOOR AIR PRODUCTS

    EPA Science Inventory

    The paper discusses the development of a framework for testing products used indoors for appropriate environmental attributes, as part of EPA's Environmental Technology Verification (ETV) program. Test protocols are being established for products that fit into three categories: ...

  9. Electric vehicle regenerative antiskid braking and traction control system

    DOEpatents

    Cikanek, Susan R.

    1995-01-01

    An antiskid braking and traction control system for an electric or hybrid vehicle having a regenerative braking system operatively connected to an electric traction motor, and a separate hydraulic braking system includes one or more sensors for monitoring present vehicle parameters and a processor, responsive to the sensors, for calculating vehicle parameters defining the vehicle behavior not directly measurable by the sensors and determining if regenerative antiskid braking control, requiring hydrualic braking control, or requiring traction control are required. The processor then employs a control strategy based on the determined vehicle state and provides command signals to a motor controller to control the operation of the electric traction motor and to a brake controller to control fluid pressure applied at each vehicle wheel to provide the appropriate regenerative antiskid braking control, hydraulic braking control, and traction control.

  10. 1. OBLIQUE VIEW OF HOIST, SHOWING CABLE DRUM, WOODEN BRAKE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. OBLIQUE VIEW OF HOIST, SHOWING CABLE DRUM, WOODEN BRAKE SHOES AND BRAKE HANDLE, LOOKING NORTH - Buffalo Coal Mine, Vulcan Cable Hoist, Wishbone Hill, Southeast end, near Moose Creek, Sutton, Matanuska-Susitna Borough, AK

  11. 2. OBLIQUE VIEW OF HOIST, SHOWING CABLE DRUM, WOODEN BRAKE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. OBLIQUE VIEW OF HOIST, SHOWING CABLE DRUM, WOODEN BRAKE SHOES, BRAKE HANDLE, AND REDUCTION GEARS, LOOKING SOUTHWEST - Buffalo Coal Mine, Vulcan Cable Hoist, Wishbone Hill, Southeast end, near Moose Creek, Sutton, Matanuska-Susitna Borough, AK

  12. 30 CFR 77.1401 - Automatic controls and brakes.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... MINES Personnel Hoisting § 77.1401 Automatic controls and brakes. Hoists and elevators shall be equipped with overspeed, overwind, and automatic stop controls and with brakes capable of stopping the...

  13. 49 CFR 570.55 - Hydraulic brake system.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ..., tubes and tube assemblies. Hydraulic brake hoses shall not be mounted so as to contact the vehicle body... restricted. Brake hoses and tubes shall be attached or supported to prevent damage by vibration or...

  14. 49 CFR 570.55 - Hydraulic brake system.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ..., tubes and tube assemblies. Hydraulic brake hoses shall not be mounted so as to contact the vehicle body... restricted. Brake hoses and tubes shall be attached or supported to prevent damage by vibration or...

  15. 49 CFR 570.55 - Hydraulic brake system.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ..., tubes and tube assemblies. Hydraulic brake hoses shall not be mounted so as to contact the vehicle body... restricted. Brake hoses and tubes shall be attached or supported to prevent damage by vibration or...

  16. Electric vehicle regenerative antiskid braking and traction control system

    DOEpatents

    Cikanek, S.R.

    1995-09-12

    An antiskid braking and traction control system for an electric or hybrid vehicle having a regenerative braking system operatively connected to an electric traction motor, and a separate hydraulic braking system includes one or more sensors for monitoring present vehicle parameters and a processor, responsive to the sensors, for calculating vehicle parameters defining the vehicle behavior not directly measurable by the sensors and determining if regenerative antiskid braking control, requiring hydraulic braking control, or requiring traction control are required. The processor then employs a control strategy based on the determined vehicle state and provides command signals to a motor controller to control the operation of the electric traction motor and to a brake controller to control fluid pressure applied at each vehicle wheel to provide the appropriate regenerative antiskid braking control, hydraulic braking control, and traction control. 10 figs.

  17. Compressed-air energy storage: Pittsfield aquifer field test

    SciTech Connect

    Bui, H.V.; Herzog, R.A.; Jacewicz, D.M.; Lange, G.R.; Scarpace, E.R.; Thomas, H.H. )

    1990-02-01

    This report documents the results of a comprehensive investigation into the practical feasibility for Compressed Air Energy Storage (CAES) in Porous Media. Natural gas porous media storage technology developed from seventy years of experience by the natural gas storage industry is applied to the investigation of CAES in porous media. A major objective of this investigation is the geologic characterization, deliverability prediction, and operations analysis of the Pittsfield CAES aquifer experiment, conducted in Pike County, Illinois during 1981--85 under EPRI/DOE sponsorship. Emphasis has been placed on applying accepted petroleum engineering concepts to the study of deliverability and on the characterization and quantification of oxygen losses which reportedly occurred at Pittsfield. Other objectives are to apply the natural gas underground storage technology and approach to a general study of CAES feasibility in porous media reservoirs, with emphasis on the practical risks and constraints of air storage in aquifer and depleted natural gas reservoirs, the effects of water on CAES operation, corrosion effects, and a review of air dehydration options.

  18. Braking, steering, and wear performance of radial-belted and bias-ply aircraft tires

    NASA Technical Reports Server (NTRS)

    Yager, Thomas J.; Davis, Pamela A.; Stubbs, Sandy M.; Martinson, Veloria J.

    1992-01-01

    Preliminary steering, braking, and tread wear performance results from testing of radial-belted and bias-ply aircraft tires at NASA Langley are described. An overview of the joint NASA/FAA/industry START program is presented. Attention is given to the Langley Test Facility, equipment and future activities.

  19. 49 CFR 571.116 - Standard No. 116; Motor vehicle brake fluids.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... packaged lot and tested simultaneously. Hydraulic system mineral oil means a mineral-oil-based fluid... humidified under controlled conditions; 350 ml. of SAE triethylene glycol monomethyl ether, brake fluid grade... when testing DOT 5 fluids) followed by an acetone or ether rinse. Pass a slow stream of filtered...

  20. Building America Case Study: Ventilation System Effectiveness and Tested Indoor Air Quality Impacts, Tyler, Texas

    SciTech Connect

    2015-08-01

    ?Ventilation system effectiveness testing was conducted at two unoccupied, single-family, detached lab homes at the University of Texas - Tyler. Five ventilation system tests were conducted with various whole-building ventilation systems. Multizone fan pressurization testing characterized building and zone enclosure leakage. PFT testing showed multizone air change rates and interzonal airflow filtration. Indoor air recirculation by a central air distribution system can help improve the exhaust ventilation system by way of air mixing and filtration. In contrast, the supply and balanced ventilation systems showed that there is a significant benefit to drawing outside air from a known outside location, and filtering and distributing that air. Compared to the Exhaust systems, the CFIS and ERV systems showed better ventilation air distribution and lower concentrations of particulates, formaldehyde and other VOCs. System improvement percentages were estimated based on four System Factor Categories: Balance, Distribution, Outside Air Source, and Recirculation Filtration. Recommended System Factors could be applied to reduce ventilation fan airflow rates relative to ASHRAE Standard 62.2 to save energy and reduce moisture control risk in humid climates. HVAC energy savings were predicted to be 8-10%, or $50-$75/year. Cumulative particle counts for six particle sizes, and formaldehyde and other Top 20 VOC concentrations were measured in multiple zones. The testing showed that single-point exhaust ventilation was inferior as a whole-house ventilation strategy.