Triangularly arranged heat exchanger bundles to restrain wind effects on natural draft dry cooling system

• Published in: Applied thermal engineering 2016-04, Vol.99, p.313-324
• Main Authors: Liao, H.T., Yang, L.J., Du, X.Z., Yang, Y.P.
• Format: Article
• Language: English
• Subjects: Air-cooled heat exchanger; Back pressure; Bundles; Circularity; Cooling systems; Dry-cooling tower; Drying; Flow and heat transfer characteristics; Heat exchangers; Natural draft dry cooling system; Triangularly arranged; Wind direction; Wind effects; Wind power generation
• ISSN: 1359-4311
• DOI: 10.1016/j.applthermaleng.2016.01.037

•Triangularly arranged heat exchanger around the dry-cooling tower is proposed.•By coupling condenser with dry cooling system, TACHE performance is obtained.•At low wind speeds, cooling performance with TACHE is inferior to that with CACHE.•Better performance can be achieved for cooling system with TACHE at high wind speeds.•TACHE can be applied to the region with the strong prevailing wind all year around. It has been commonly recognized that the crosswind may deteriorate the cooling performance of the natural draft dry cooling system with vertically arranged heat exchanger bundles around the circumference of dry-cooling tower. With the purpose for restraining the adverse effects of ambient winds, a novel triangular configuration of heat exchanger bundles is proposed in this work. The air-side flow and heat transfer models coupled with the circulating water heat transfer process are developed for two kinds of natural draft dry cooling systems with the conventional circularly arranged and novel triangularly arranged heat exchanger bundles, by which the flow and temperature fields, mass flow rate of cooling air, outlet water temperature of heat exchanger and turbine back pressure are obtained. Three wind directions of 0°, 90°, and 180° are investigated at various wind speeds for the natural draft dry cooling system with triangularly arranged heat exchanger bundles, which are compared with the conventional system with circularly arranged heat exchanger bundles. The results show that the thermo-flow performances of the natural draft dry cooling system with triangularly arranged heat exchanger get improved significantly at high wind speeds and in the wind direction of 180°, thus a low turbine back pressure can be achieved, which is of benefit to the energy efficiency of the power generating unit. The natural draft dry cooling system with triangularly arranged heat exchanger is recommended to apply to the regions with strong prevailing winds all year around.