Design and Fabrication of Erect Rotary Valve for Internal Combustion Engine by Wenbo Dong Department of Engineering Technology A Thesis Submitted in Partial Fulfillment of the Requirements for the Degree of Master of Science in Engineering Technology. May 2016 Thesis committee: Dr. Charles H. Perry Dr. Walter W. Boles Dr. Vishwas N. Bedekar ACKNOWLEDGEMENTS Dr. Charles Perry, my mentor for my study and life in MTSU, for his teaching, supporting and motivation during my research. Dr. Walter Boles for serving on my thesis committee. Dr. Vishwas Bedekar for serving on my thesis committee and supply of heat treatment material. Mr. Rick Taylor for his machining work support, advice and the patience he gives to his students. Mr. William Harper, my friend, for his advice and welding technique support. Mr. Jingsai Liang, my friend, for his mathematics and MATLAB technique support. Mr. Justin Roberts, my friend, for his English writing advice. ii ABSTRACT The internal combustion engine, performing mechanical work by harnessing combustion, has proved to be a convenient, efficient and reliable path in the last decades. However, the complexity of the inner structures and mechanisms act as the essential barrier which limits the further improvement of the internal combustion engine. The valve train, the structure that operates the combination gas exchange, contributes its friction to the internal mechanism loss which consumes power and confines the thermal efficiency. Based on the shape and operation of conventional poppet valves, a manufacturer has to sacrifice the piston top design and compression ratio to prevent valve-piston interference. This innovational research focuses on not only the valve train structure and driving method but also the shape and operating condition of the valve itself. As a new valve design, a unique Erect Located Cone Rotary Valve will be spinning inside of the combustion chamber to operate combination gas exchange. The thesis introduces the history of the internal combustion engine and the classification of the valve configuration. The research exposes the problems of the conventional poppet valve and discusses the advantages and limitations of previous rotary valve designs. The thesis presents detailed analysis, calculation and parameters of the erect rotary valve and also describes the limitation and the compromise of the current erect rotary valve design. In the end, the research provides the feasibility and direction of future development. iii TABLE OF CONTENTS LIST OF FIGURES ...................................................................................................... vi CHAPTER ONE. LITERATURE REVIEW ................................................................. 1 CHAPTER TWO. INTRODUCTION ........................................................................... 5 Pushrod Valve System ................................................................................................ 7 Overhead Camshaft Valve System ............................................................................. 9 CHAPTER THREE. OBJECTIVE .............................................................................. 12 CHAPTER FOUR. THEORY ...................................................................................... 14 Performance .............................................................................................................. 14 Indicated Horsepower ........................................................................................... 14 Volumetric Efficiency ........................................................................................... 15 Valve ......................................................................................................................... 16 Valve Opening Area .............................................................................................. 16 Valve Operation .................................................................................................... 17 CHAPTER FIVE. VALVE DESIGN ........................................................................... 19 Valve-Piston Interference ......................................................................................... 19 Valve Floating ........................................................................................................... 20 Single Overhead Camshaft ....................................................................................... 21 Transverse Layout .................................................................................................... 21 Erect Rotary Valve .................................................................................................... 24 CHAPTER SIX. ENGINE PARTS FABRICATION ................................................... 27 Cylinder Head Modification ..................................................................................... 27 Camshaft Modification ............................................................................................. 28 Valve Fabrication ...................................................................................................... 29 Surface Manufacturing.......................................................................................... 29 Heat Treatment ...................................................................................................... 31 Valve Drive Train Fabrication .................................................................................. 32 Timing Setting .......................................................................................................... 35 Camshaft Related Parameter Setting ........................................................................ 35 Base Circle ............................................................................................................ 36 Lift......................................................................................................................... 36 iv Valve Opening Area .............................................................................................. 37 Duration ................................................................................................................ 37 Setting of Erect Rotary Valve ............................................................................... 37 Actual Parameter for the Erect Rotary Valve ........................................................ 41 CHAPTER SEVEN. TEST .......................................................................................... 43 Erect Rotary Valve Components Contact Surface Hardness Test ............................ 43 Compression Test ..................................................................................................... 44 CHAPTER EIGHT. CONCLUSION ........................................................................... 45 Future Improvement ................................................................................................. 46 Variety of Material ................................................................................................ 46 Ball Shape Valve ................................................................................................... 46 Camless ................................................................................................................. 48 Multi-Vent Valve ................................................................................................... 48 Accomplishments and Future Direction ............................................................... 49 REFERENCES ............................................................................................................ 51 v LIST OF FIGURES Figure 1: Four-Stroke Engine Principle ......................................................................... 5 Figure 2: Pushrod Valve Mechanism ............................................................................. 7 Figure 3: Valve-Piston Interference and Its Damage ..................................................... 8 Figure 4: Overhead Camshaft Valve Mechanism .......................................................... 9 Figure 5: SOHC Transverse Rotary Valve ................................................................... 10 Figure 6: Engine Timing Diagram ............................................................................... 17 Figure 7: Dual Overhead Camshaft Valve Mechanism Layout ................................... 22 Figure 8: Cylinder Deactivation Technology ............................................................... 23 Figure 9: DOHC Transverse Rotary Valve Layout ...................................................... 24 Figure 10: The Erect Rotary Valve Principle ............................................................... 25 Figure 11: Modified Cylinder Head ............................................................................. 27 Figure 12: Modified Valve Cover ................................................................................ 28 Figure 13: Extended Camshaft..................................................................................... 29 Figure 14: Finished Contact Surface............................................................................ 30 Figure 15: The Erect Rotary Valve Drive Train ........................................................... 33 Figure 16: Bevel Gear Mechanism .............................................................................. 34 Figure 17: Camshaft Cross Section Diagram..............................................................