Experimental Study On Flow And Heat Transfer Characteristics In A Helical Minichannel With Built-in Coils

Jacket type heat exchanger is widely used in food,chemical,pharmaceutical and other industries.With the rapid development of advanced manufacturing technology and manufacturing technology in recent years,such as high integration of electronic equipment,high heat flow density of car battery and so on,the matching heat exchange equipment also started the miniaturization process.This paper presents 5 kinds of spiral minichannels with internal springs,The laminar flow experiments of deionized water were carried.out.The heat transfer and flow properties of the smooth helical minichannels and 5 kinds of helical minichannels with internal springs are compared and analyzed.Based on the previous work,The influence of the geometrical parameters on the flow and heat transfer characteristics of the smooth spiral minichannels is investigated.The result shows that with the decrease of the spring spacing S or the increase of the length L in the spiral minichannel,The number of Nu in the spiral microchannel also increases,But the effect of comprehensive heat transfer is limited.The reason is that compared with the increase of heat transfer coefficient,the increase of pressure drop loss is more significant.lt is recommended to use helical minichannel with built-in springs to enhance heat transfer without considering the loss of pressure drop.In the Simulation test,The result shows thatThe influence of spiral diameter on flow and heat transfer is greater than that of pitch because The influence of spiral diameter on secondary flow intensity is greater than that of pitch.