Study Of Using The Natural Cold Source In The Base Station Air-condition System

The air conditioning systems perennial cooling which made a huge energy consumption was needed in the base station due to its particularity.How can make the air-conditioning systems room run energy-saving has always been a concern.It was also treated as a key project to promote energy-saving emission reduction work in the12th Five-Year Plan.The outdoor natural source of cold energy saving was the most direct and effective way, this paper introduced the common use of natural cold source, and proposed the conception of the critical temperature difference and the energy saving evaluation criteria. Use the building energy simulation software DeST to simulate five base stations of the five typical cities in different construction climate partition.Through simulation and comparison of the result of the three mode which were only air-conditioning,only ventilation,air conditioning-ventilation cooling joint operation,found that:When the outside temperature was above the dew point and below15℃in the open air, open the ventilation system;A joint air-conditioning-ventilation cooling when the outside temperature was between15℃to25℃;When the outside temperature was higher than the design control temperature, stop the introduction of the fresh air, use air conditioning cooling only.The length of mechanical cooling time can be effectively reduced by this method.So the power consumption of the base station was reduced too.Due to the cold winter outside temperature is too low, there will be a risk of condensation if the new cold air was introduced directly in the cold region. While the outside temperature generally higher throughout the year in the subtropical region. So the available time using ventilation cooling technology was shorter in these two regions while it was much longer in hot in summer and cold in winter region,up to5,000hours a year.It can save air-conditioning system electricity20%to53%in that way.This paper also analyzeed the energy-saving potential of the two Isolated Heat Exchanger energy-saving way, including heat pipe heat exchanger system and Ethylene Glycol Solution heat exchanger system, the available time in different regions is derived by comparison of their energy-saving effect.In order to study the internal airflow organization in base station when using ventilation, the software Airpark was used to simulate the temperature field and velocity field distribution in the base station under certain air volume and temperature supplied.The simulation found that the distribution of the temperature within the base station was uneven, impacted by the velocity field greatly.There was significant temperature gradient in the vertical direction, the temperature changed from15℃to30℃.Compare the impact of the supply air temperature to the average temperature of base station,It can be found that the rational supply air temperature is12℃to13℃, and the rational air volume is about50times per hour, then a much better airflow organization in the base station can be formed.