Recent Engine Tribological Investigations at Tokyo City University Akemi Ito Associate Professor Automotive Engine Laboratory TriboBr November, 2010

Photograph of Musashi Institute of Technology in 1931 Musashi Institute of Technology Established in 1929 Renamed as Tokyo City University last year Engineering Knowledge Engineering Environmental and Information Studies Urban Life Studies Human Life Sciences

Recent view of Tokyo City University

Biomedical Engineering Operation room

Atomic Energy Research Laboratory

Hydrogen fueled engine automobile “Musashi 8”

History of Engine Research in Musashi Institute of Technology and Tokyo City University Hydrogen Energy Research Center Automotive Engine Laboratory Engine Research Laboratory 1951 Prof. Furuhama Hydrogen fueled engine Combustion of engines - Thin film sensors - Engine tribology - H2 engine for practical use - Advanced H2 engine - Fuel cell - Liquid H2 pump & tank - Engine tribology

Research Piston Friction Hydrogen Engine Wrist-pin Lubrication Concerning environmentally friendly engines Oil Consumption

Research staff of the Automotive Engine Laboratory Dr. Akemi Ito, Associate professor Dr. Hidekazu Suzuki Dr. Dalwoo Kim Hideyuki Iwasaki Shuma Aoki 7 graduate students 2 undergraduate students 1 technician Private Sector Government (2010) 12 private companies Budget

CO 2 emissions in Japan Requirements for the reduction of CO 2 emissions A reduction in CO 2 emission from engines is required

Reduction in CO 2 emissions from engines Using alternative fuels (Biofuels) Improvement In the thermal efficiency of engines Poor bio-resources in Japan Main approach for reduction in CO 2 emissions from engines in Japan Reduction of friction losses in engines

Reduction of friction losses in engines Supply energy [%] Engine load [%] Friction loss Output Cooling loss Exhaust loss Incomplete combustion Gasoline engine for in-town use

Reduction of friction losses in engines Engine speed [rpm] Friction Mean Effective Pressure [kPa] Main bearing Piston, Piston-ring, Connecting-rod Valve train Oil pump Water pump, Alternator Friction loss

Recent activities in engine tribology at TCU (1) Friction reduction of pistons By Dr. Suzuki

Principle of measurement of piston friction force Head Cylinder block Floating liner Load sensor Piston

Measurement apparatus for piston friction forces 浮動ライナ部 ピエゾロードワッシャ ライナ支持環状薄板 燃焼圧 シール部 ２重ライナ構 造 Floating liner Combustion gas sealing parts Piezo-type load sensors Lateral stopper Floating liner

Glass liner Coating to reduce reflection Oil film observation method

Comparison of measured / calculated piston friction Piston A, Piston BPiston C Piston A Piston B Piston C Piston A Piston B

Measured/calculated friction forces Calculated Measured

1200 rpm, 380 kPa (IMEP) Pmax=2.2 MPa, 0 ～ 720 deg. Piston C Piston A Piston B Oil film thickness Observed oil film on piston skirts

Recent activities in engine tribology at TCU (2) Friction reduction of piston-rings

Effect of piston-ring tension on friction

Friction loss and engine oil consumption

Recent activities in engine tribology at TCU (3) Reduction of engine oil consumption

Engine oil consumption Customers’ operating costs Clogging of diesel particulate filter Piston ring sliding surface Piston ring gap Back of piston ring Increase in particulate matter

Measurement apparatus for cylinder bore deformation

Sulfur caused oil consumption Exhaust gas Oil Engine Method of measurement of oil consumption

Typical measurement results of cylinder bore deformation Block type 1Block type 2

Oil consumption of Block Types 1 and 2

Conclusions Improvement of thermal efficiency of engines Increase in cylinder pressure Increase in severity of sliding surface Reducing friction losses For environmentally friendly engine Using alternative fuels Negative effect on lubricants and Sliding surface Tribological investigation of engines occupies an important role in the research of environmentally friendly engines