The investigation of air temperature characteristics in large-span manufacture area of clean room

Abstract The main aim of this study is to predict the temperature characteristics in large-span manufacture area of clean room using the Computational Fluid Dynamics (CFD). The CFD model was established based on a large semiconductor plant and verified by measured data. Then, the effects of these factors including fan filter unit (FFU) configuration, building envelope and fresh air system on temperature distribution were analyzed. The results indicate that both increasing FFU air velocity and placement rate can decrease maximum temperature difference. The 33% placement rate has a higher performance-price ratio because the maximum temperature difference differs slightly at 33% and 50% placement rates. The number of FFU can decrease by 415 when placement rate reduces from 50% to 33%. Increasing the thermal resistance of building envelope can also improve the temperature distribution. And changing the thermal insulation properties of roof is more effective than changing that of external wall. So, more attention should be paid to the thermal insulation properties of roof. For fresh air system, fresh air needs to mix well with original air to reduce the effect on temperature. Thus, fresh air inlet port should be inserted into the return air plenum in the design.