New Equipment and Methodology to Perform High Speed ValveTrain Dynamics Testing and Analysis

With the increased need for variable and high-speed valvetrains for improved performance and economy, greater importance must be placed on valvetrain testing and prove-out. To make an accurate assessment of valvetrain capability and high-speed dynamics, improved test and analysis capability is needed.

The objective of this paper is to provide the necessary information for others to understand and perform high-speed valve train dynamics testing using current state-of-the-art equipment. It includes the use of a differential laser vibrometer to measure complete valve lift and velocity and a Rotational Analysis System (RAS) that easily and quickly reduces the data to plots and compares measured valvetrain dynamics to theoretical models. Also covered are valve closing velocity measurements, calculated valve accelerations, torque, torsional vibration, sample rate and filtering. Effects of torsional vibration, sample rate and filtering on measurements are also demonstrated.