Performance Study Of Flow And Heat Transfer Of Heat Exchanger With Louver Baffles

Shell-and-tube heat exchanger is very reliable because of the structure,design and manufacture simple, low production costs, able to withstand hightemperature and pressure, the process is easy to clean, etc. They are widely usedin the power, energy, nuclear energy and chemical industry. However thetraditional segmental baffle shell and tube heat exchanger shell side and thepresence of fluid flow swerving dead zone, its large resistance, large pressuredrop. Improving and optimizing shell-and-tube heat exchanger shell side of thestructure, reducing the shell-side flow and reduce pressure drop dead zone, theheat exchanger for energy saving is significant.In view of this, we propose a new louver baffles shell-and-tube heatexchanger, the establishment of a three-dimensional mathematical model for thevalidation; access to its local velocity and temperature fields, and analyzed;three-dimensional numerical simulation to pitch into the different fluid media, baffles affect the heat exchanger shell side pressure drop, heat transfer and overallperformance were studied. Main results are as follows:(1) Louver baffle heat exchanger shell flow field distribution, nosegmental baffle heat exchanger shell fluid flow direction suddenly changed,reducing and eliminating the heat exchanger shell flow dead zone, effectivereducing the heat exchanger shell drop.(2) Louver baffle heat exchanger shell temperature field distribution,fluid tubes full contact, did not like the arched plate heat exchanger aftersegmental baffles significant deterioration in the local heat transfer area.(3) Within the heat exchanger inlet velocity scope of this study, theoverall performance louvres baffle heat exchanger is superior segmental baffleheat exchanger, compared with segmental baffle heat exchanger, When the fluidmedium is water, louvres baffle heat transfer coefficient decreased0.52%to0.82%when the fluid medium is air and oil, louver baffle heat exchangercoefficients were increased by2.56%~3.36%and2%~4.65%; the shell sidepressure drop in order to reduce15.87%~16.5%,21.25%~30.11%and12.98%~15.07%; unit pressure drop of the heat transfer coefficient in turn increase by15.8%~18%,12.92%~16.18%and15.8%~16.2%.(4) Within the heat exchanger inlet velocity range studied in this paper,and segmental baffle heat exchanger for comparison, the level of louver baffleheat exchanger, heat transfer coefficient vertical louver baffle heat exchanger respectively decrease in the range of6.55%~6.87%,0.52%~0.82%; drop thansegmental baffle heat exchangers decreased by14.78%~15.4%,15.87%~16.5%;the unit under pressure drop heat transfer coefficient in order to improve the8.77%~9.25%,15.8%~18%. Therefore, the vertical blinds baffle heat exchangeris better than horizontal louver baffle heat exchanger effect.(5) Within the heat exchanger inlet velocity range studied in this paper,compared with segmental baffle heat exchanger, louver baffle angle of30°,40°and50°of louver baffle heat changers thermal coefficients were reduced by0.09%~0.52%,7.3%~7.8%and11.78%~12.33%; it reduces the pressure dropof16.5%~15.87%,20.89%~30.67%,37.13%~37.81%; the unit pressure lowerheat transfer coefficient increased by15.8%~16.2%,24.36%~24.73%,28.74%~29.27%. Louver baffle heat deflector angle increases, the heat transfercoefficient of the unit is about the big drop, the heat better.(6) Within the heat exchanger inlet velocity range studied in this paper,blinds baffle spacing is300mm, louver baffle spacing is400mm heat transfercoefficient than the segmental baffle heat exchanger in order to reduce the5.59%~6.78%,0.52%~0.82%; which in turn reduces the pressure drop12.56%~12.94%,15.87%~16.5%; its unit pressure drop increases the heat transfercoefficients were19.21%~21.41%,15.8%~18%.