Valvetrain Friction - Modeling, Analysis and Measurement of a High Performance Engine Valvetrain System

Analysis of dynamics and friction resistance in the cam-tappet system

“…7a. The oil lubrication causes values of the friction forces to be a few times lower (2)(3)(4) than in the case of constant friction coefficients µ c−t and µ t−p . Time histories of the tappet rotation angle ε are shown in Fig.…”

“…It is found that tappet rotation is affected by design and operating conditions, and depends primarily on camshaft speed. The use of advanced mathematical models to quantify power loss at cam/tappet contact, tappet/bore contact and camshaft bearings was presented in Calabretta et al (2010). Calculated and measured friction data for the valve train of a high speed passenger car engine were compared with those obtained from tests on a motored cylinder head test rig.…”

Modeling of Variable Valve Timing on High Performance Engine using Power-Oriented Graphs Method

“…At the meantime the resistance torque of the camshaft, M res ,was acquired using an experimental motoring test-rig as described in Reference [3]; in particular it was focused the attention in sensitivity variation by speed, temperature and oil viscosity. Before using the processing data for model validation, the signals acquired were elaborated with Matlab script, in particular was rebuild the engine timing signals to calculate the engine revolution, one of the input signals, and the cam phases, intake and exhaust, one of the output signals (see As shown in the figure can be appreciate the good results between simulation and actual physical system which confirms the energetic approach modeling is very useful facing complex problems above all when you have to collide with the production ECU less performance than the micro controller used for example for Hardware-In-The-Loop or Rapid Prototyping.…”

Experimental Measurement of Frictional Torque in End Pivoted Roller Finger Follower Valve Train

“…[6]. In this experimental research work, the friction at cam/roller interface has been experimentally ISBN 978-93-84422-76-9 6th International Conference on Developments in Engineering and Technology (ICDET-2017) Bangkok (Thailand) Feb. [6][7]2017 investigated under actual engine operating conditions.…”

“…[6]. In this experimental research work, the friction at cam/roller interface has been experimentally ISBN 978-93-84422-76-9 6th International Conference on Developments in Engineering and Technology (ICDET-2017) Bangkok (Thailand) Feb. [6][7]2017 investigated under actual engine operating conditions. A gasoline engine valve train Toyota INZK, as shown in figure 2 has been instrumented, for the very first time without making any modifications to the engine head to measure the drive torque.…”