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为获得较好性能的强化传热翅片,在百叶窗翅片的基础上,提出4种不同连续递增或递减攻角的百叶窗翅片,并对其传热及流动特性进行研究.不同翅片的攻角分别为:LF1+2° (22°,24°,26°,28°,30°,28°,26°,24°,22°),LF2+3°(18°,21°,24°,27°,30°,27°,24°,21°,18°),LF3 0°(攻角均为30°),LF4-3°(30°,27°,24°,21°,18°,21°,24°,27°,30°),LF5-2° (30°,28°,26°,24°,22°,24°,26°,28°,30°).计算结果显示,虽然连续变攻角百叶窗翅片的换热性能略低于固定攻角的百叶窗翅片,但其流动阻力大大降低,综合性能更好.说明在相同的压降下,连续变攻角百叶窗翅片的换热性能更好.在Re-408～1230时,LF2和LF4的综合性能最好.“,”In order to obtain better performance of louvered fin,four different louvered fins with the successively increasing or decreasing louvered angle are proposed based on the louvered fin and the characteristic of heat transfer and fluid flow of new louvered fins are investigated.The attack angle of five different louvered fins are LF1+2°(22°,24°,26°,28°,30°,28°,26°,24°,22°),LF2+3°(18°,21°,24°,27°,30°,27°,24°,21°,18°),LF3 0° (uniform attack angle 30°),LF4-3°(30°,27°,24°,21°,18°,21°,24°,27°,30°) and LF5-2°(30°,28°,26°,24°,22°,24°,26°,28°,30°).The numerical results show that the heat transfer coefficient of louvered fins with continuous variable angle of attack are slightly lower than the uniform louvered angle fin,but the flow resistant decreases dramatically Therefore,the overall performance of louvered fins with continuous variable angle of attack is better than that of uniform louvered angle fin.This means that under the same pressure drop,the louvered fins with continuous variable angle of attack has better heat transfer performance When Re =408 ～ 1230,the overall performance of LF2 and LF4 are the best.