THERMAL SCIENCE

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Optimization of volumetric efficiency of a small wankel engine using genetic algorithm

ABSTRACT
In this work, port CA strategies for maximizing engine volumetric efficiency of a commercial rotary engine are studied. The Internal Combustion Engines computer program, which simulates an actual working processes, has been used. Overall performance characteristics such as the cycle efficiency, engine power are calculated by a mathematical model. The model is calibrated with data obtain from a measured in-cylinder pressure, and validated against the experimental data. Intake opening and closing time (IO and IC), exhaust opening and closing time (EO and EC) are chosen as optimization variables when volumetric efficiency was taken as the objective function. First, the intake opening time is the only optimization variable and it can be found that intake opening time is in advance as engine speed is increased. Second, four variables including IO, IC, EO and EC have been taken as the optimization variables, a further increase in volumetric efficiency was obtained, with the highest gain being of 1.03% at 17000 r/min. But opening the EO very late will reduce the power.
KEYWORDS
PAPER SUBMITTED: 2018-05-04
PAPER REVISED: 2018-12-08
PAPER ACCEPTED: 2019-02-17
PUBLISHED ONLINE: 2019-03-09
DOI REFERENCE: https://doi.org/10.2298/TSCI180504058Z
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