Previous studies have demonstrated that tubeside maldistribution can adversely affect the thermal performance of some heat exchangers. Therefore, a study was conducted to determine the effect of tubeside maldistribution on the thermal performance of the condensers used in multistage flash (MSF) distillation plants. This paper shows that the tubeside maldistribution does not impair the thermal performance of these heat exchangers. The major reasons are the long-tube lengths and the low-effectiveness values. It is shown, however, that the tubeside maldistribution can not be neglected for shorttube length and high-effectiveness heat exchangers. I NTRODUCTI ON Previous studies have demonstrated that tubeside maldistribution can adversely affect the thermal performance of some heat exchangers. McDonald and Eng (ref. 1) stated that the maximum deviation of total heat transfer with nonuniform tube flow characteristics from that obtained with uniform flow was about 4 percent for a crossflow heat exchanger. However, Fleming (ref. 2), Cowans (ref. 3), and Weimer and Hartzog (ref. 4) discussed the significant adverse impact of tubeside maldistribution on the thermal performance of high-effectiveness, cryogenic heat exchangers. Very recently, Collier (ref. 5) listed maldistribution of flow as one of the major causes of degraded thermal performance of heat exchange equipment. In particular,
Collier stated that the direct impact on the thermal performance may be relatively small for many industrial heat exchangers even though the extent of the flow maldistribution may be considerable. He also discussed cryogenic heat exchangers which he claimed are the exception. He stated that flow nonuniformity will seriously impair the performance of high-effectiveness, cryogenic heat exchangers because of the very low-temperature differences at which such exchangers are designed to operate. The writer is not aware of any publications which determined the effect of the tubeside maldistribution on the thermal performance of the heat exchangers used in MSF desalination plants. With the commonly used crossflow MSF desalination plant configuration, the stage effectiveness values can become as high