Experimental investigation on automotive valve jump/bounce detection : through use of knock sensor and energy comparison

Abstract

This paper details the experimental work performed on the verification of the dynamic kinematic performance of camshafts designed and fabricated for operation on a turbocharged Kawaski 600cc spark ignition engine. The engine can operate to 12500rpm and the camshafts were shown to incur jump/bounce at speeds higher than 12500 rpm as designed. The Original Equipment Manufacturer OEM naturally aspirated 600cc engine was turbocharged for Formula SAE competition which gave the motivation to design bespoke camshafts suited for the introduction of the turbocharger in the flow stream. Cam valve timings and lobe profiles for the intake and exhaust valves were designed using Ricardo Wave and Valdyn. The purposely built test stand is detailed together with the sensing and data analysis performed for jump/bounce detection. A commercial knock sensor mounted on the cylinder head together with data analysis in LabView were used.