Measurement Of Indoor Thermal Environment And Optimization Of Air Conditioning System In Large Spaces

Although tall space buildings can better meet the increasingly rich daily needs of people in the new era,for air-conditioning systems,the larger the space,the more complex the airconditioning system is required to meet the indoor needs for temperature,humidity,and fresh air.Due to the characteristics of high rise,large size,and versatility of tall space buildings,the rationality of the air conditioning system will directly affect the energy-saving effect of the building and the creation of air flow organization.Especially in sports large space buildings,the indoor air flow organization will directly affect the results of ball games.In addition,in the air conditioning season,the air-conditioning energy consumption of tall space buildings accounts for more than half of the total energy consumption of buildings.Therefore,in the context of low-carbon energy conservation,how to save more energy while meeting the indoor requirements for thermal comfort and airflow organization is also the top priority of current work in the HVAC field.This thesis takes a university gymnasium in Jinan as the research object,and uses Airpak software to model the gymnasium,and tests the gymnasium to verify the reliability of the model.In addition,the thesis proposes a set of evaluation system of air distribution in large space based on previous research,through which different working conditions are evaluated and reflected by the percentile system.The main research contents of the article include the following aspects:First of all,the thesis analyzes the measured results of the gymnasium and finds that the gymnasium has serious air leakage from the enclosure structure,resulting in increased load,reduced return air volume and increased fresh air ratio.The energy consumption is about 69%higher than that when the enclosure structure has no air leakage.Secondly,the article simulates the cooling conditions of the gymnasium in summer,and studies 23 conditions of different air supply speeds,air supply angles,air supply temperatures and outdoor temperatures,and evaluates and compares the simulation results of each condition through the air distribution evaluation index introduced in this thesis.The results show: the satisfaction of working face temperature,wind speed and energy utilization coefficient increase,decrease and decrease with the increase of air supply wind speed,when the outdoor temperature is 32 ℃,the air supply temperature is 14.7 ℃,and the air supply angle is 0 °,selecting the air supply speed of 6 m/s-7 m/s can obtain a relatively ideal effect,and the air supply speed of 6.5m/s is the best;the satisfaction of working face temperature,wind speed and energy utilization coefficient decrease,decrease and increase with the increase of air supply angle;When the outdoor temperature is 32 ℃,the air supply temperature is 14.7 ℃,and the air supply speed is6.5 m/s,the ideal effect can be obtained by selecting the air supply angle of 0 °-5 °,and the air supply angle with a downward tilt of 5 ° can achieve the best effect;working face temperature satisfaction,wind speed satisfaction and energy utilization coefficient increase first and then decrease,increase and increase with the increase of air supply temperature.Under the conditions of air supply speed of 6.5 m/s and air supply angle of 5 °,when the outdoor temperature is 32 ℃,31 ℃ and 30 ℃ respectively,the best effect can be obtained by selecting the air supply temperature of 14.7 ℃,15.2 ℃ and 15.7 ℃ respectively,and the corresponding cooling capacity of the unit is 235 k W,219 k W and 204 k W;the wind speed satisfaction and energy utilization coefficient of the working face increase with the decrease of the outdoor temperature,while the temperature satisfaction will increase,decrease or increase first and then decrease with the influence of the outdoor temperature and the supply air temperature.With the decrease of the outdoor temperature,the temperature satisfaction will become more and more sensitive to the change of the supply air temperature,the gymnasium provides cooling in summer and when the outdoor temperature is within the range of 32 ℃-30 ℃ and the indoor supply air temperature is constant,The cooling capacity of the unit will decrease by 4%-5% when the outdoor temperature decreases by 1 ℃,when the outdoor temperature is fixed,the cooling capacity of the unit will decrease by 2%-3% when the air supply temperature increases by 1 ℃.