Multi-hole orifices have better performance than single-hole orifices. In this paper, multi-objective optimization of multi-hole orifices is performed using a Fluid-Solid Interaction (FSI) analysis and multiobjective genetic algorithm (NSGA II). In all numerical analysis, the governing equations of the solid and the governing equations of the fluid are carried out for orifice and fluid around orifice, respectively. All calculations are made for a 16-hole orifice with circular holes. The design variable in the optimization process is the distance between the holes of the orifice and thus the amount of shrinkage or expansion of the orifice geometry. The objective functions are the pressure drop created on the sides of the orifice, the deformation and tension created in the orifice structure, which should be maximized, minimized and minimized, respectively. In the results section, the Pareto front are presented which represent useful information for designing the multi-hole orifices geometry, and five orifices are also introduced as final design options that have better performance. The results of the sensitivity analysis of the various parameters are also presented and discussed in detail in the multi-hole orifices.
