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Transient Maneuvers and Pressure Analysis on an Automotive Torque Converter

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Transient Maneuvers and Pressure Analysis on an Automotive Torque Converter Michigan Technological University Digital Commons @ Michigan Tech Dissertations, Master's Theses and Master's Reports 2021 Transient Maneuvers and Pressure Analysis on an Automotive Torque Converter Abigail A. Hempy Michigan Technological University, [email protected] Copyright 2021 Abigail A. Hempy Recommended Citation Hempy, Abigail A., "Transient Maneuvers and Pressure Analysis on an Automotive Torque Converter", Open Access Master's Thesis, Michigan Technological University, 2021. https://doi.org/10.37099/mtu.dc.etdr/1186 Follow this and additional works at: https://digitalcommons.mtu.edu/etdr Part of the Other Mechanical Engineering Commons TRANSIENT MANEUVERS AND PRESSURE ANALYSIS ON AN AUTOMOTIVE TORQUE CONVERTER By Abigail A. Hempy A THESIS Submitted in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE In Mechanical Engineering MICHIGAN TECHNOLOGICAL UNIVERSITY 2021 © 2021 Abigail A. Hempy This thesis has been approved in partial fulfillment of the requirements for the Degree of MASTER OF SCIENCE in Mechanical Engineering. Department of Mechanical Engineering-Engineering Mechanics Thesis Co-Advisor: Jason Blough Thesis Co-Advisor: Darrell Robinette Committee Member: Carl Anderson Department Chair: William W. Predebon Table of Contents List of figures .................................................................................................................... vii List of tables ..................................................................................................................... xvi Preface............................................................................................................................. xvii Acknowledgements ........................................................................................................ xviii Abstract ..............................................................................................................................xx 1 Introduction .................................................................................................................1 1.1 Objectives .........................................................................................................1 1.1.1 Torque Converter Basics.....................................................................1 1.1.2 Transmission Basics............................................................................5 2 Literature Review........................................................................................................6 2.1 Torque Converter Experimentation ..................................................................6 2.2 Transmission Experimentation .........................................................................7 2.3 Simulation ........................................................................................................7 3 Experimental Set-Up ...................................................................................................9 3.1 Test Cell Set-Up .............................................................................................10 3.1.1 Fixtures and New Hardware .............................................................11 3.1.1.1 Shafting ...........................................................................11 3.1.1.2 Test Stand........................................................................12 3.1.2 Dynamometer Controller ..................................................................14 3.2 Transmission Instrumentation ........................................................................15 3.3 Torque Converter Instrumentation .................................................................16 iii 4 Methods.....................................................................................................................25 4.1 Hardware Set-Up Procedures .........................................................................25 4.1.1 Test Cell Set-Up ................................................................................25 4.1.2 Inverter Cart Set-Up ..........................................................................30 4.1.3 Telemetry Set-Up ..............................................................................35 4.2 Hardware Power-up Procedures .....................................................................38 4.2.1 Contactors .........................................................................................38 4.2.2 Starting the Cart ................................................................................41 4.2.3 Starting the Test Cell ........................................................................42 4.3 Software Procedures .......................................................................................45 4.3.1 Dynamometer Control ......................................................................45 4.3.2 Solenoid Controller Software ...........................................................47 4.3.3 Telemetry Software ...........................................................................54 4.4 Calibration Procedures ...................................................................................60 4.4.1 Inverter Cart Calibration Procedure ..................................................60 4.4.2 AC Dynamometer Calibration Procedure .........................................63 4.5 Steady State Test Development ......................................................................64 4.5.1 Spin Losses .......................................................................................64 4.5.1.1 Input Dynamometer Spin Loss Testing ..........................65 66 4.5.1.2 Transmission Loss ..........................................................67 4.5.1.3 AC Dynamometer Loss...................................................67 4.5.2 Warm-Up Procedure .........................................................................67 4.5.3 Performance Testing & Controlled Slip ...........................................67 4.6 Transient Test Development ..........................................................................68 4.6.1 Clutch Apply and Release .................................................................69 4.6.2 Negative Torque Sweep ....................................................................69 4.6.3 Coast Down Test ...............................................................................71 iv 4.6.4 Negative Input Torque with Slip.......................................................72 4.7 Data Acquisition .............................................................................................74 4.7.1 LabView ............................................................................................75 4.7.2 Signature Acquisition........................................................................75 4.7.3 Digital FV Telemetrics .....................................................................77 4.7.3.1 Recording Telemetry Data ..............................................77 4.7.3.2 TOMBox Triggering .......................................................78 4.8 Data Processing ..............................................................................................80 5 Results .......................................................................................................................81 5.1 Performance Testing .......................................................................................81 5.2 Transient Testing ............................................................................................84 5.2.1 Clutch Apply and Release .................................................................84 5.2.2 Negative Torque Sweep ....................................................................87 5.2.3 Coast down........................................................................................89 5.2.4 Negative Input Torque with Slip.......................................................92 6 Summary and Conclusions .....................................................................................100 7 Recommendations ...................................................................................................101 7.1 Testing Recommendations ...........................................................................101 7.2 Instrumentation Recommendations ..............................................................101 References ........................................................................................................................104 A Supplementary Graphs for Transient Tests.............................................................107 A.1 Negative Torque Sweep ...............................................................................107 v B Troubleshooting ......................................................................................................110 C BorgWarner Electric Motor Data Sheet ..................................................................111 D Calibrating the Inverter Cart ...................................................................................112 E Telemetry Post Processing ......................................................................................113 F Fill Procedure for Transmission..............................................................................115 G Checklist for Starting TC Cell ................................................................................116 H Transmission Swap Procedure ................................................................................117
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