1. Have a certain strength, stiffness and leakproofness and do not deform and leak during operating. 

2. Has a certain capacity and has a certain voltage stabilizing function to eliminate the influence of uneven distribution of air at inlet, the indoor average air flow velocity is generally required to be less than 1.5 m/s. 

3. Have a certain diversion effect, to avoid occurring of dead corner and vortex area as much as possible. 

4. Have simple structure, which is easy to maintenance. 

5.The hydrodynamic performance of water cooling structure is good.