| With the development of economic and people’s living standard, likethe energy consumption, the uniformity of indoor air distribution, thermalcomfort have been integral parts of sustainable building assessment. Highair quality and comfortable living environment have been the healthyprotection of human life. How to maintain the uniformity of air distributionand thermal comfort while saving energy has been the direction andpurpose of researchers.Only the indoor airflow can be predicted using FLUENT alone.FLUENT software is difficult to simulate the control of system online,while TRNSYS software is able to achieve. However, it is assumed that theindoor air is evenly mixed and has no difference. Based on this, this paperproposes the method of TRNSYS-FLUENT coupling simulation. TRNSYSsoftware is used to simulate the VAV air conditioning system and itscontrol of a commercial building in Shanghai, while FLUENT software isused to simulate the indoor temperature distribution and velocitydistribution of one air-conditioned room. According to the predictiveanalysis of the indoor thermal comfort and indoor air distribution, thecontrol of VAV system can be improved and optimized.Firstly, for the3-D model of the air-conditioned room, temperaturedistribution and velocity distribution can be obtained through the FLUETNsimulation. The result shows that different supply air volume can result indifferent airflow distribution. The supply air volume is automaticallycontrolled by the indoor temperature controlling loop, according to thedeviation of the sampled indoor temperature value and the set point of the temperature sensor. And, the location of the indoor temperature sensordirectly affects the controlling of supply air volume and further affects theindoor airflow distribution and the energy consumption of air conditioningsystem.Using the method of TRNSYS-FLUENT coupling simulation, theeffect of the indoor temperature sensor’s locations on the thermal comfortand energy consumption of the air conditioning system has been studied.The results show that the location of the indoor temperature sensor canaffect indoor air velocity and temperature patterns. The different locationscan result in different indoor thermal comfort and energy consumptions ofVAV system.Secondly, in order to meet indoor thermal comfort, the temperaturecorrection control strategy has been proposed. Through correcting theindoor temperature set point, the effect of the different indoor temperatureset points on the thermal comfort is studied. It concludes that the setting ofindoor temperature set point affects indoor thermal comfort. A reasonableindoor temperature set point helps improve the indoor thermal comfort.Finally, in order to satisfy the uniformity of indoor air distribution, thesupply air optimal control strategy based on multi-sensor is proposed.According to optimize the set point of supply air temperature, the supplyair volume is adjusted in order to obtain uniform indoor air distribution. Itcan be concluded that for the object of this paper, this optimal controlstrategy can improve the indoor air distribution uniformity and interiorcomfort. |
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