Numerical Investigation on Double Shell‐Pass Shell‐and‐Tube Heat Exchanger with Continuous Helical Baffles

Abstract

A double shell‐pass shell‐and‐tube heat exchanger with continuous helical baffles (STHXCH) has been invented to improve the shell‐side performance of STHXCH. At the same flow area, the double shell‐pass STHXCH is compared with a single shell‐pass STHXCH and a conventional shell‐and‐tube heat exchanger with segmental baffles (STHXSG) by means of numerical method. The numerical results show that the shell‐side heat transfer coefficients of the novel heat exchanger are 12–17% and 14–25% higher than those of STHXSG and single shell‐pass STHXCH, respectively; the shell‐side pressure drop of the novel heat exchanger is slightly lower than that of STHXSG and 29–35% higher than that of single shell‐pass STHXCH. Analyses of shell‐side flow field show that, under the same flow rate, double shell‐pass STHXCH has the largest shell‐side volume average velocity and the most uniform velocity distribution of the three STHXs. The shell‐side helical flow pattern of double shell‐pass STHXCH is more similar to longitudinal flow than that of single shell‐pass STHXCH. Its distribution of fluid mechanical energy dissipation is also uniform. The double shell‐pass STHXCH might be used to replace the STHXSG in industrial applications to save energy, reduce cost, and prolong the service life.