Abstract:
Presently all engine makers are continuously struggling for enhancing overall efficiency and reducing fuel consumption during engine operation. Mechanical and thermal losses are mainly responsible for engine fuel losses. Engine manufacturers have made considerable advancements in optimizing design of engine parts, their material and lubricants for minimizing losses in engine operation. In order to further reduce frictional losses, researchers are also focusing on different coatings [ 1] and surface treatment techniques [ 2] to be used on contacting metal surfaces in engine operation. Only 12% of the available fuel energy reaches to driving wheels with approximately 15% being dissipated as mechanical losses which mainly comprise of frictional losses [ 3]. Valve train friction losses are approximately responsible for 7.5 to 21% of total mechanical losses in the engine [ 4]. Slippage/skidding between rolling contacts can increase friction and wear. Focus of this research work is to check effect of WPC surface treatment process on slippage/skidding at camshaft roller contact in End pivoted finger follower valve train. A series of tests under different camshaft speeds and lubricant oil inlet temperatures have been carried out using both unmodified roller (original) and modified roller (WPC treated roller) to investigate the impact of this surface texturing technique on the slip at camshaft roller contact, experimentally. The results have clearly revealed significant reduction in slip at camshaft roller contact for WPC treated roller as compared to original roller under similar operating conditions at low lubricating oil temperature. In this research report, previous literature review, WPC surface treatment process, experimental setup, data acquisition system, experimental procedure and results have been presented in detail.
