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The steady state forces and moments on a railway wheelset including ange contact conditions. PDF

396 Pages·2017·15.37 MB·English
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Loughborough University Institutional Repository The steady state forces and moments on a railway wheelset including flange contact conditions. ThisitemwassubmittedtoLoughboroughUniversity’sInstitutionalRepository by the/an author. Additional Information: • A Doctoral Thesis. Submitted in partial fulfilment of the requirements for the award of Doctor of Philosophy of Loughborough University. Metadata Record: https://dspace.lboro.ac.uk/2134/16979 Publisher: (cid:13)c Barrie Vaughan Brickle Rights: This work is made available according to the conditions of the Cre- ative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0) licence. Full details of this licence are available at: https://creativecommons.org/licenses/by-nc-nd/4.0/ Please cite the published version. LOUGHBOROUGH UNIVERSITY OF TECHNOLOGY LIBRARY , I . i AUTHOR , :. ..... ........................ _._ .. _..S _ ..P. ...,..\..C.......I.....<......L....'." :": . •.. .". .....g...... ............................. .............................. ........... , . .. : ~ ..... ~?.:..!.. . ~9: .. ·_· .. ·. . ·_ .. ·.. Q·~·r,.. .J ..~·~. . I·~ L.. ........................ "-""--'-'''''' , VOL NO . CLASS MARK . fOR",R FERENCE.,ONV .. ','::: '. , ' " "-' " I , ! I i {, . i ; \ \ THE STEADY STATE FORCES AND MOMENTS ON A RAILWAY WHEELSET . mCLUDmG FLANGE CONTACT CONDITIONS by Barde Vaughan Briclde A Dootoral Thesis Submitted in partial fulfilment of the requirements for the award of Ph.D. of the Loughborough University of Technology. August 1973 Supervisor: Professor F. D. Hale8 Department of Transport Technology ~ by Barrie Vaughan Briclde, 1973. SUMMARY Railwa;y' vehicles aref'itted with ccned wheels to provide a measure of stability, but it can be shcwn that since the forces,between , wheel and track are non-conservative, dynamic instability occurs at a certain critical speed. Under these oonditions the wheelsets sway from side-to-side of the, track with the flanges of the wheels contacting the rails. ' This can lead to derailment when the wheel climbs up the' rail and eventually jumps off'. The forces which exist between wheel and rail are due to the phenomenon known as "creepage", and various theories exist which predict these forces in the plane of the contact area. An investigation has been carried out into these theories with the railway wheelset problem in view, particularly the flange contact case. It is possible, by assuming small displacements which avoid flange contact, to carry out a linearised of the lateral dynamics stu~ of a wheelset, but the presence of the wheel flanges introduces a non linearity into the problem. A mathematical model of a wheelset and track has been defined based on real wheels with a "worn" tyre profile and real track. Computer programs have been written which calculate the contact points when the wheel set is'displaced laterally and yawed by various amounts, including flange ,contact conditions. Up to three contact points can exist between the wheelset, and track. Forces in the contact areas have been calculated using the various theories assuming the wheelset to be rolling along the track ata constant velocity in a displaced position. These forces have been manipulated to give the total forces and, moments on thO', wheelset and are presented for various vertical load dist'ributions and for ~arious 'angular and lateral displacements of the wheelset from its central position. Although theories exist which predict the forces for flange type contact, i. e. very elongated contact ellipse with a large amount of spin .. , "-'.~, .... ' .... " .~ . .. . ,)' ,; " loughborougbolUniversity ql.o}echnp!c~y c .lib"'Y· n Date ~"". Class O'$7s$TO\ Ace. No. --, "':~ S.!:';:'.U present, it became apparent during the course of the investigation that very little experimental evidence was available for such conditions. As a result a roller rig was built to provide this data, and measurements were made of· the lateral force due to various amounts of lateral creep and spin on elongated contact ellipses. Results from these tests have been compared with the available theories and show reasonable agreement. CONTENTS . Page 1. Introduction •••••••••••••••••••••••••••••••••••••••••••••••• 1 2. Review of Rollirig Contact Theories, and Experiments 2.1 Basic Theory ••••••••• ~. •••••••••••" • •••.••••••••• '• .••• ~. B 2.2 Theoretical Review • ~ ••••••••••••" • ••••••••••••••••••• e". 11 2.3 Review .••••••••••••••••••••••••••••••••••• 23 ~xperimental 3. Theories used in Present Analysis The Limiting Case of Infinitesimal Creepageand Spin• •• 47 The Limiting Case of Large Creepage and Spin •••••••••• 54 ArBitar,y Creepage and Spin •••••••••••••••••••••••••••• 57 Numerical Theory ••••••..•.•••••.• '• •.•.•.••...• 57 Simplified Theor,y ••••••••••••••••••••••••••••• 64 4. Mathematical Model of Wheelset and Track I Introduction ••••••••••••••••• .' •••••••••••••••••.•••••• 69 Rail Geometry ••..•.••••...••••..•••••••.•.•.••••• ~ ••.• 70 ........................................ Wheel Geometry 74 ........................................ Contact Points 79 4.4.t Wheelset in Central Position •.•••.•••.. ~ ....•• 81 4.J...2 Wheelset Moved Laterally Only •••••••••••• '• •••• 82 4.4·3 Wheelset Yawed Onl\v ............................ . 88 4.4.4 Wheelset Moved Laterally and Yawed •••••••••••• 100 Ellipses •••.•...•...••••••.•••....•.........•• 105 .Contac~ Creepages and Spin ..................................... . 116 Forces ••.••••.•...•.•••.•........•••.••.•.•••...•.••.. 121 5. Comparison of Theories '1 .........................................• Introduction 124 Results ............................................... . 125 Page Discussion •••••••••••••••••••••••••••••••••••••••••••••• 129 Wheelset Displaced No Yaw •••••••••••• ,129 Lateral~, = = = !ZA TZe -82.29kN , Tz" 0 Wheels et Displaced No Yaw •••••••••••• 131 Lateral~, T = -82.29kN , Tz = 0 , Tz = -82.29kN zA , 8 ,c Wheelset Displaced and Yawed •••••••••• 132 Lateral~ Tz = - 82.29kN , Tz = 0 • 'Tz ~ - 82.29kN A 8 e , Conclusions ••••••••••••••••••••••••••••••••••••••• -•••••• 134 6. Comparison of Wheels et Forces Using New and Worn Rails ..........................................•. 6.1 Introduction 137 6.2 Results ••••••••••••••.•••••••••••••.••••••••••••••••• ~ •• 137 Discussion and Conclusions •••••••••••••••••••••••••••••• 138 7. Derailment Ratio Introduction 159 ••••••••••• 4 •••••••••••••••••••••••••••••••• Existing Formulae for Derailment Ratio ••••••••••••.••••• 160 Nadal's Formula •••••••••••••••••••••••.•••••.••• 160 Wagner's Formula •••••••••••••••••••••••••••••••• Johansen's Fo~ula ••••••••••••••••••••••••••• ~ •• •.................................•.............• Results Discussion and Conclusions •••••••••••••••••••••••••••••• 8. Experimental Investigation 8.1 Introduction •••••••••••••••••••••••••••••••••••••••••••• 170 , 8.2 Rig Description ••..••••••••••••••••••••••••••••••••••••• 171 Creepages and Forces .••• ~-•••••••••••••••..•.•.•••••••••• 185 .............•....•..•......................... 8.4 Procedure 190 ............................... ................ . 8.5 Results 197 ~ ,..------------------------------- ---- Page 8.6 Discussion •..............•........... ~ ........•..•.•••• 207 8.6.1 . Validity, Accuracy and Repeatability o~ Results 207 8.6.2 Correlation with Theor,y, ••••••••••••••••••••••• 219 ....................... Conclusions and Recommendations 229 General Discussion and ConcluSions •••••••••••••••••••••••••• 235 16. References •.......•.....•..•.•...••.•••.•.•.••••.•.•.•••..•• 246 Acknowledgements •••••••••••••••••••••••••••••••••••••••••••• 254 12. Appendices Derivation of the Relative Slip Equations for Steady Rolling ••••• 255 2. Simplified Theory •••••••••••••••••••••••••••••••••••••• 257 Adaption of Governing Parameters for use in Simplified Theory •••••••• 4. Comparison of Results Obtained Using Subroutine ROL with Kalker's Simplified Theory Program ••• 268 Program Descriptions •.•.•••.•••••••••.••••••.•• '• ••••••• 6. Coordinate Geometry ••••••••••••.••••••••••••••••••••••• 7. Longitudinal Creep, Lateral Creep and Spin on Roller Rig ••••••• 363 8. Angle of Yaw, 'i', of Upper Wheel Relative to Lower Wheel •••••••• 9. Contact Ellipse Semi Axes, a,b ••••••••••••••••••••••••• 370 Sheet •................................ 10. Experimenta.l Data 374 11. Roll Effects on Experimental Rig •••••••••••••• "• •••••••• 376

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Adaption of Governing Parameters for use in. Simplified .. dltterenoe between a spherioal traotion distribution' aoting over the. , whole oontact area
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