Simulation of Mass and Pressure Dynamics of In-Cylinder Charges at Variable Valve Lift Clearance in Four Stroke Spark Ignition Engine

Abstract

The performance of any given four stroke IC engine cycle is
influenced by various parameters during service condition.
SOLIDWORKS 2017 version was used to simulate the effect of
different valve lift clearance (ranging from 5-13 mm) on the mass
and pressure of in-cylinder charges in four stroke spark ignition
engine speeds (ranging from 1000-12000 rpm). The study revealed
that for simulation at a particular engine speed, more charges were
ingested into the cylinder as the valve lift clearance increased. This
led to effective combustion process, but can sometimes result in
losses if the valve opening clearance is very wide. For example, at
12000 rpm, the 13mm valve lift showed a pressure of 1.12 ????????????
while the 5mm valve lift showed a pressure of 0.89 ????????????. Higher
valve lift clearance led to increase in the quantity and mass of
charge ingested into the engine cylinder, thus, more loses and vice
versa. The mass intake was observed to reduce at higher engine
speeds when compared to low speeds. This is because the engine
piston moved very fast with intense heat (converting some charges
into gas-vapour) requiring less time for charges in the intake
manifold to enter the engine.