On the constant wall temperature boundary condition, the heat transfer and pressure drop characteristics were investigated numerically by heat conducting oil YD-300 used as working fluid. The comprehensive heat transfer and heat enhancement mechanism were analyzed．The results showed that Nusselt number and flow resistance coefficient were the highest at the condition of pitch τ≈1.96. The effects on enhanced heat transfer and resistance coefficient were very small for half-coil jackets at varying pitch for the non-overlapping structure τ>1.96. Nusselt number decreased with pitch shortened for the overlapping structure τ<1.96. 1.96>τ≥1.86 was beneficial for heat transfer because the speed field was improved near the overlapping and heat exchange walls. But fields coordination was reduced between speed, temperature gradient and static pressure gradient when τ≤1.47, also heat transfer was declined and resistance was improved.
Jing ZHANG Yanqiu ZHANG Jianhua WU
. Effect of Varying Pitch and Overlap Scale on Enhanced Heat Transfer of Half-coil Jackets[J]. The Chinese Journal of Process Engineering, 2017
, 17(4)
: 697
-703
.
DOI: 10.12034/j.issn.1009-606X.216382
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