Study of indoor thermal environment and stratified air-conditioning load with low-sidewall air supply for large space based on Block-Gebhart model

Abstract

At present, the commonly used mathematical calculation method of stratified air-conditioning load for large space building was proposed by the form of nozzle air supply. However, there is no complete cooling load calculation methods of stratified air-conditioning with low-sidewall air supply system for large space buildings which are widely used in recent years. This paper takes a scale model laboratory which has the airflow distribution of low-sidewall air supply system as study object and based on Block-Gebhart (B-G) model to predict the indoor thermal environment distributions. Afterwards, we used the calculation methods of radiative and convective heat transfer loads which were proposed by our research group to calculate the stratified air-conditioning load and verified by the experiments. The results show that the relative errors range of theoretical and experimental values of indoor air temperatures, inner wall temperatures and stratified air-conditioning load are ranging from −5.440% to 2.473%, −5.024%–3.277% and −6.47% to 4.04%, respectively. This indicates that the B-G model can accurately predict the indoor thermal environment distributions and the stratified air-conditioning load calculation method that described in this paper is also accurate and feasible. This study will make up for the insufficiency of traditional method which is unable to calculate the stratified air-conditioning load with low-sidewall air supply for large space buildings. In addition, the factors that influencing the indoor thermal environment and stratified air-conditioning load were analyzed, which it will contribute to the design and optimization of stratified air-conditioning system for large space buildings.