Influence of Tube Arrangement on the Thermal Hydraulic Performance of a Membrane Helical-Coil Heat Exchanger

摘要

Thermalhydraulic performances of membrane helical-coil heat exchangers in in-line and staggered arrangements, are numerically investigated. The influences of Reynolds number, dimensionless pitch, and arrangement on heat transfer and flow are discussed. Moreover, the axial and tangential velocity distributions were presented for various pitches and arrangements. The results show that the membrane helical-coil arrangement has a profound effect on the thermalhydraulic performance. For the smaller radial pitch (s ₁/d  1.8), the heat transfer coefficient in in-line arrangement is higher than that in staggered arrangement. Meanwhile, the in-line arrangement gives a significantly higher friction factor than the staggered arrangement. However, for the larger radial pitch (s ₁/d ≥ 1.8), the coil arrangement appears to have no effect on the heat transfer and friction factor. In addition, the average Nusselt number Nu and the friction factor f for in-line and staggered arrangements were calculated and correlated against the Reynolds number and structural parameters. According to the thermalhydraulic performance evaluation criterion, the staggered arrangement is recommended as the optimal coil arrangement.View full textDownload full textRelated var addthis_config = { ui_cobrand: "Taylor & Francis Online", services_compact: "citeulike,netvibes,twitter,technorati,delicious,linkedin,facebook,stumbleupon,digg,google,more", pubid: "ra-4dff56cd6bb1830b" }; Add to shortlist Link Permalink http://dx.doi.org/10.1080/10407782.2012.707061