Computational fluid dynamics simulation on a thermal power plant with air-cooled condenser

Abstract

The environmental wind speed, wind direction, and surroundings of the air-cooled condenser are parameters that may affect the cooling system performance. This article concentrates on the hot air recirculation phenomenon and its dependence on ambient winds are numerically simulated using the computational fluid dynamics code, FLUENT. In this study, two different wind directions (cases A and B) and two different wind speeds are considered. Results show that the hot air recirculation increases with the increment of velocity speed. Case A has a critical wind direction angle. Wind causes an air temperature increase at the fan inlet due to hot air recirculation, resulting in the deterioration of the heat transfer performance. In case A, fan inlet temperature is about 2.2 °C higher than fan inlet temperature in case B. Heat rejection in case B is 10.5% higher than case A. Increment of the wind speed from 3 to 9 m/s leads to 5.9 °C rise in fan inlet temperature and heat rejection reduction about 27%. The effect of the hot air recirculation phenomenon occurs at 9 m/s in case A.

Keywords

Air-cooled condensers wind speed hot air recirculation computational fluid dynamics

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References

EPRI. Comparison of alternate cooling technologies for US power plants: economic, environmental, and other tradeoffs. EPRI Technical Report. Report no. 1005358, August 2004. California: EPRI.

Kroger

. Air-cooled heat exchangers and cooling towers thermal flow performance evaluation and design. Oklahoma: Penn Well Corporation, 2004.

Zhao W, Lei M, Wang S, et al. Numerical simulation and analysis of the hot air recirculation phenomenon observed in direct air-cooled system. In: Proceedings of the 3rd IEEE conference on industrial electronics and applications, Singapore, 3–5 June 2008, vol. 1–3, pp.1624–1628.

Duvenhage

Kroger

. Plume recirculation in mechanical draught heat exchangers. Heat Transfer Eng 1995; 16(4): 42–49.

Du Toit

Kroger

. Modeling of the recirculation in mechanical draught heat exchangers. S Afr Inst Mech Eng 1993; 9: 2–8.

Bredell

Kroger

Thiart

. Numerical investigation of fan performance in a forced draft air-cooled heat exchangers. Appl Therm Eng 2006; 26: 846–852.

Wang

Zhang

Zeng

. CFD simulation on a thermal power plant with air-cooled heat exchanger system in north China. Int J Comput-Aided Eng Softw 2008; 25(4): 342–365.

Patankar

. Numerical heat transfer and fluid flow. Washington, DC: Hemisphere, 1980.