Numerical Simulation On Heat Transfer Performance Of Shell-and-tube Heat Exchanger

Using soft fluent, numerical simulation studies were conducted for shellflow field and heat transfer characteristic of helical baffles and vertical bafflesheat exchanger. The result showed that, for the same flowrate, the pressure losson the shell side of helical baffles exchanger was lower than of that on theshell side of vertical baffles heat exchanger. As flowrate increasing, thepressure drop in helical baffles and vertical baffles heat exchanger tendedupwards. With the increase of the helical angle, the pressure drop of helicalbaffle tended downwards.The capacity of heat transfer on the shell side ofhelical baffles exchanger was a little lower than that on the shell side ofvertical baffles exchanger. The heat transfer coefficient of unit pressure drop ofhelical baffles was 30 percent lager than that of vertical baffles.For the wholeperformance, the helical baffles heat exchanger was superior to the verticalbaffles heat exchanger.Based on the helical baffles, this thesis put forward an improvedscheme, and numerical simulation was made for. The results showed that, theseparation efficiency increased as particle diameter turned larger. For particleswhose diameter was 100 micron, the separation efficiency could reach 72.5percent when the inlet wind velocity was 16 meter per second. For particleswhose diameter was less than 30 micron, the separation efficiency was muchlower,21.1 percent to the most, while the separation efficiency would be higherwhen the particle diameter was bigger than 30 micron. The heat exchangerseparation efficiency would rise as inlet wind velocity increased. When theinlet wind velocity increased from 10 meter per second to 16 meter per second,separation efficiency of particles whose diameter was 100 micron could beincreased from 62.5 percent to 72.6 percent. The high wind velocity could noteffectively improve the separation efficiency, but increased the flow resistance enormously. With the increase of the particle concentration,the separationefficiency rose.The heat exchanger separation efficiency ranged from 59.5percent to 70.4 percent when particle concentration was between 15 g per stereand 200 g per stere.