A new method to estimate the resistance coefficients of net panels modeled as porous media

Abstract

Modeling net panels as thin porous media is an effective approach to carry out computational fluid dynamics (CFD) simulations of fishing nets and aquaculture cages. Existing methods to estimate the resistance coefficients for these porous media are based on simplified analytical models that relate these coefficients to the drag and lift coefficients of the panel. We propose a new method that uses a CFD model of the flow through a layer of porous media to estimate the resistance coefficients from regression analysis with experimental data. To increase the computational performance, the CFD model response is pre-calculated and interpolated in the regression analysis. The proposed method is applied to different net panels compared with existing methods. Results show that it provides better results than previous methods. Estimating both the inertial and the viscous resistance coefficients always provides better results than estimating just the inertial coefficients and it does not complicate the regression analysis with the proposed method. The method is easy to implement, fast and it could be used to estimate the resistance coefficients of materials other than net panels, since it does not make any assumption about the geometric characteristics of the actual material.