Lighting And Thermal Environment Optimization Research Of Core Lighting Atrium In Guangzhou

Lighting atrium has been applied more and more widely recently,while it also brings harsh thermal environment and increase energy consumption because of glass roof structure.Influence of glassroof’s sunshading measure,roof ventilation,atrium geometric configuration on lighting and thermal environment in core lighting atrium has been studied by using research methods of investigation,experiment and simulation optimization in this paper.A numerical simulation method suitable for core lighting atrium is established.Optimal combination of non-dimension factors representing geometric configuration of atrium is also presented to providing reference for engineering practice and architectural design.Characteristics and influencing factors of atrium thermal environment have been analyzed.Atrium space elements influencing indoor thermal environment have been studied by field and literature research.Typical architectural parameters of lighting atrium are confirmed and equivalent height width ratio SAR*≤4,which can be basis of followup experiment and optimization.Experiments were carried out on Guangzhou’s A Library whose SAR* equals to 0.628 and glass roof is flat,as well as newly completed Guangzhou’s B Hospital whose SAR* 1.386 and glass roof zigzag.Operative temperature top is selected as the evaluation index of heat and humidity environment in non-artificial environment.Comparing the library’s thermal environment between different conditions,sun-shade and ventilation are beneficial to the atrium thermal environment,and sun-shade better than ventilation.Comparing atrium thermal environment between two testing building,the hostipta’s thermal environment is better.P-1 model and S2 S model are compared in verification calculation,finding that temperature relative error in both calculations is within 15% and P-1 model has better accuracy and faster computation speed compared with S2 S model.Feasibility is verified effectively using FLUENT to simulate atrium thermal environment combined field experiments with numerical simulation.Optimization of AR,SAR and the angle of the lighting top is conducted by ECOTECTE lighting analysis and CFD thermal environment analysis.Research shows that AR is the critical factor in atrium illuminance.With the decrease of AR and increase of SAR and angle,the thermal environment of atrium is better.At the same time,theoretical analysis shows that the direction of solar radiation heat gain from small to large is the south direction,the north direction,the east or west direction.Therefore,design of core lighting atrium should consider increasing area adjacent atrium,atrium height and glass roof angle,reducing glass roof area,on the premise of meeting the illuminance requirements.In this paper,the geometrical characteristics with better thermal and lighting environment are as follows: AR=1/5,SAR=4.Glass should be toward the south,and the dip angle γ=75°,when shapes of atrium and glassroof are square.