换热管内置喷注螺旋强化传热数值模拟研究

Numerical Simulation Study on Heat Transfer Enhancement of Heat Exchanger Tube with a Built-in Spouting Spiral Tube

在换热管内设置喷注螺旋管,同时通过螺旋管施加喷注,改变螺距及喷注孔布置,研究其强化传热及阻力特性。换热管尺寸为57 mm×3.5 mm,喷注螺旋管尺寸为10 mm×1 mm,螺距设置范围为60~140 mm,喷注孔布置密度为单位螺距内2~6个。研究表明:换热管内置喷注螺旋管对传热起到强化作用,同时由于内插件和喷注导致其阻力变大,随着螺距的增大,对传热和阻力的影响都呈减小趋势;通过对换热管传热和阻力的综合性能分析可知,内置喷注螺旋管不一定使换热管的综合性能增加,也可能会使其减小。当螺距P为100 mm,单位螺距内设置4个喷注孔时,综合性能表现最优,达到最大值1.8。

The spouting spiral tube is set in the heat exchanger tube.Spouting is produced through holes on the spouting spiral tube.The pitch of the spiral tube and the density of spouting holes on the spiral tube is changed to study the characteristics of heat transfer enhancement and increased resistance.The dimension of the heat exchanger tube is57 mm×3.5 mm,the dimension of the spouting spiral tube is10 mm×1 mm,the pitch of the spouting spiral tube is from 60 mm to 140 mm,the density of spouting holes is 2 to 6 per pitch.The results show that:the built-in spouting spiral tube of heat exchanger tube can enhance the heat transfer,and its resistance increases due to the built-in spouting spiral tube and the spouting.With the increase of the pitch of the spiral tube,the influence on heat transfer and resistance decreases gradually;the comprehensive performance analysis of heat transfer and resistance of the heat exchanger tube shows that the built-in spouting spiral tube will not necessarily increase the comprehensive performance of heat exchanger tube,and its performance may also be reduced.When the pitch P is 100 mm and 4 spouting holes per pitch are set,the comprehensive performance is the best,which reaches the maximum value of 1.8.