Since the global warming, the hot and humid climate becomes a great challenge for the production and health of sow during summer. The conventional cooling systems consumes a lot of energy by cooling the whole building, so a water-cooled overhead sow cover system that sims to enhance the heat loss of the sow without elevating the indoor relative humidity(RH) was designed and optimized using CFD to simulate the cooling effect and evaluate the impact parameters. A 3D CFD model within enclosed space have been developed and analyzed under unsteady state condition comparing the k-ε turbulence models such as the standard, RNG, and realizable models to validate the field experimental data. In addition, the structure of the cooling system by changing the tube spacing(10cm, 15cm, 20cm) and the curtain(W or W/O) in front of the sow occupied zone, the thermal condition of the ambient air and inlet water temperature combined with water flow was optimized during the simulation. The RNG k-ε model was found to be more suitable for this model with the lowest error of 1% at 10cm tube spacing by the validating experimental data of vertical temperature gradient within the cooled cover. The more dense tube spacing could increase the cooling effect by larger heat transfer area. Adding the curtain could not only reduce the air velocity across the sow occupied zone, but also the heat transfer with ambient air. The ambient air and inlet water temperature and water flow rate also affects the cooling efficiency. The optimized model according to the production system will be considered in the future study.