Natural ventilation in a lege space with heat source: CFD visualization and taguchi optimization

Abstract

Louvre-equipped generic enclosed (LEGE) space with heat source and guiding vents is commonly seen in many buildings, heat transfer equipment and has plenty of practical applications. In the current work, natural wind- driven convection in a LEGE space system with a mono-centric heat source under five louvre configurations and different wind speeds are analyzed. The system walls are assumed adiabatic, and a heat source is introduced at the centre with five different levels of heating in the range of 100 and 400 W/m2. The system is placed in an ample rectangular space to generate natural wind flow conditions. The efforts of conducting several experiments are reduced by applying Taguchi method and Anova is used to rank the experiments based on the responses from CFD simulations. Firstly 3D steady RANS equations are solved using the Finite volume approach where RNG k-ω the model was chosen for turbulence modelling. The Nusselt number and temperature of the heat source were noted down as responses for each case. Secondly, the percentage contribution of different factors on the temperature of heat source and optimum experiment were explored using ANOVA technique. The results are reported in contours and velocity vectors inside the enclosure, disclosing the heat flow and air circulation under different design configurations. Results show that louvres position had a maximum of 5 percent effect on the responses than other factors. From the ANOVA method, results show that the contribution of air velocity is around 80%.