MA Zhixian, ZHANG Jili, SUN Dexing. Effects of anchor-type ducts on film condensation of HFC245fa on horizontal tube bundle[J]. CIESC Journal, 2014, (3): 849-854.
MA Zhixian, ZHANG Jili, SUN Dexing. Effects of anchor-type ducts on film condensation of HFC245fa on horizontal tube bundle[J]. CIESC Journal, 2014, (3): 849-854.DOI: 10.3969/j.issn.0438-1157.2014.03.012.
part of the inundation effect induced by falling condensate formed on neighboring tubes above
has hindered the heat transfer of shell and tube condenser for a long time. This paper put forward a scheme to eliminate the tube row effect by anchor-type ducts and further investigated its effect on film condensation heat transfer coefficient (CHTC) of HFC245fa on the tube bundles. A 4-line-wide and 5-row-deep tube bundle consisting of smooth tubes and finned tubes
with two columns out of the four equipped with the anchor-type ducts
was built in the test section. Equivalent outside diameter and active length of all tubes in the test section were 19.05 and 500 mm
respectively. The modified Wilson plot method was used to determine the waterside convection heat transfer. The short-period-calibrate method and homogenous method were used to determine the tube row effect with high-precision. Results show that: ① tube row effect can be well controlled by the anchor-type ducts; ② adverse effect of anchor-type duct on CHTC of each tube in the bundle is negligible; ③ with the anchor-type duct
more than 20% (or 30%) of smooth tubes (or enhanced tubes with three dimension fins) can be saved for a tube bundle in a shell-tube condenser of diameter 600 mm. This paper can be used to guide the design of high efficiency shell-tube condenser.