Experimental and Numerical Flow Investigation of Intake Manifold and Multi Criteria Decision Making on 3-cylinder SI Engine using Technique for Order of Preference by Similarity to Ideal Solution

In this paper, technique for order of preference by similarity to ideal solution(TOPSIS) method is used to find the best compromising design of intake manifold for a 3-cylinder engine considering mean value of torque, torque at 3500 rpm, mean value of brake mean specific consumption (BSFC) and BSFC at 3500 rpmas four objective functions. To calculate the objective functions, engine simulation is carried out using GT-SUITE software. The engine simulation code (ESC) is built from experimental combustion pressure data which come from engine test bench. Results of such simulations are then used to perform TOPSIS and some design points are obtained considering similar values for the objective functions weights. Due to high value of torque and low value of BSFC one of the obtained designs is selected as the best compromising design. To evaluate performance of the selected design, the flow rate is completely investigated experimentally and numerically. Results show that the flow is distributed in three runners as uniform, so that the maximum difference of flow rate is 0.49% which means the uniform air charging for all the three cylinders. Also, good compatibiliy is found between the CFD and experimenal results from flow rate point of view.