Abstract:

Jet cooling is one of effective ways to transfer the great flux density heat, and the heat sink shape of jet impingement is a key point affecting heat transfer. The new cone heat sink proposed is numerically simulated by using RNGk-ε turbulence model under the condition of jet impingement through a single spray nozzle and the result is verified by experiments. The result indicates that the cooling effect of heat sink with a single cone is better than that of usual flat plate heat sink, and when compared with the latter, the former has an additional transition region where is a secondary impingement which strengthens the heat transfer. The greater theRe number becomes, the better effect of the cone heat sink will be; the numerical simulation about different cone angle (15°-60°) of heat sinks shows that 45° cone angle of heat sink provides a higher value of number than the others; whend₁ (diameter and conical bottom) /d (jet diameter) is 1-3, and whend₁/d is about 2.5, it gets a higher value of number compared to the others; whenH (height of the jet) /d is 5, nothing about the cooling effect of heat sink is so good as thatH/d is about 5.

Key words: boundary layer, heat transfer enhancement, impinging jet, numerical simulation, cone heat sink