Simulation of flow field of a ventilated and occupied animal space with different inlet and outlet conditions

Abstract Simulation of flow field of a ventilated space of a biological object is necessary to determine heat exchange between the object and its environment. In this paper, flow fields of a ventilated space occupied by twenty randomly placed virtual cows are characterized under four different inlet and outlet situations. A three-dimensional turbulence model is used to characterize the flow field. The four inlet and outlet cases are: (1) ceiling-baffle inlet with airflow parallel to the wall with the outlet fan located at the center of the opposite wall, (2) wall-baffle inlet with airflow parallel to the ceiling with the outlet fan located at the center of the opposite wall, (3) the same as in Case 2 but with two inlets and outlets, in which one inlet and one outlet is located in each sidewall, and (4) center-ceiling baffle inlet and an outlet fan located at the center of each sidewall. There is significant variation in the uniformity of the flow field between the four air inlet/outlet locations. Air distribution is more uniform when air enters parallel to the ceiling from two sidewall inlets and exits through two sidewall outlets. The distribution is less uniform when air enters parallel to the ceiling from one sidewall only. Variations in sensible and evaporative heat fluxes are significant between cow locations for the same air inlet/outlet configuration, and for the same cow under the different air inlet/outlet configurations considered.

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