| The indoor air quality(IAQ) and building energy saving have become important fields in HVAC. A better indoor air environment can be created by underfloor air distribution(UFAD) in low power situation, and there was not a calculation method of this system's cooling load so far, the calculation method of UFAD's cooling load was studied in this paper.A series experiment were carried out in the IAQ chamber and CFD was used to simulate underfloor air distribution. Two calculation methods of single heat's cooling load reduction was suggested in this paper, formulation method and heat distribution method. By comparing of the fluid field and validating of the engineering method, the result shows that we can calculate the cooling load reduction of single heat by the formulation method. On the base of accuracy, the author establishes the database of the cooling load reduction coefficients, and introduces how to use database to calculate the UFAD's cooling load by taking one condition for example.According to the date base of cooling load reduction coefficients, the variation laws of difference temperature and velocity of air distribution, and its effects of the distribution parameter at different height of work area was studied. The results show that at the same air distribution velocity and different air distribution temperature, the effects of single heat's cooling load coefficient by difference temperature are different. At the same difference temperature, the cooling load coefficient of single heat increases as the velocity of air distribution increases. The result also shows that the effects of cooling load reduction coefficient at different work area height by air distribution temperature are different. At the same difference temperature, the cooling load coefficient at different work area height increases as the air distribution velocity increases, but the variety is unobviouse. |
