Effects of by-pass damper on shell side flow and heat transfer performance of a heat exchanger with continuous helical baffles

In the present paper, numerical simulations are carried out to based on FLUENT study the effects of locations and width of the by-pass damper on shell side flow and heat transfer of a shell-and-tube heat exchanger (STHX) with continuous helical baffles by using periodic model and periodic boundary conditions. The results show that under the same mass flow rate M and the width of the sealing strips W, with the increase of the sealing strip number, the shell side heat transfer coefficient h is 9.3%~41.7% higher than that without sealing strips while the overall pressure drop Δp increases by 37.5%~189.7%. Four uniformly distributed sealing strips is the optimal structure. Under the same mass flow rate M and the sealing strip number, with the increase of the width of the sealing strips W, the h increases by 1.6%~34.5% while the Δp increases by 11.1%~146.6%.