Correction and analysis of calculation equations of the thermal plume above kitchen appliances

Abstract In kitchen environment, an efficient kitchen hood is especially demanded to ensure the provision of a healthy, comfortable and energy efficient working environment. The most accurate kitchen ventilation design method should be based on the heat gain of the appliances. In this paper the calculation equations of convection plumes, above kitchen appliances, were investigated. The heat source of cooking appliances is assumed to be a point heat source, and the temperature and velocity distributions are assumed to match the Gaussian distribution. In the kitchen environment, at the extraction point, the convection flow of the transitional region has not yet fully developed. Thus, the derived general plume equation is inaccurate for the transitional region. Nevertheless, when the position of the virtual origin is individual adjusted in a practical application, the results are reasonably accurate. The calculation experience formulas of the virtual origin position of air flow rate are worked out.