Abstract
Adverse wind effects on the thermo-flow performances of air-cooled condensers (ACCs) can be effectively restrained by wind-proof devices, such as air deflectors. Based on a 2 × 300 MW coal-fired power generation unit, two types (plane and arc) of air deflectors were installed beneath the peripheral fans to improve the ACC’s cooling performance. With and without air deflectors, the air velocity, temperature, and pressure fields near the ACCs were simulated and analyzed in various windy conditions. The total air mass flow rate and unit back pressure were calculated and compared. The results show that, with the guidance of deflectors, reverse flows are obviously suppressed in the upwind condenser cells under windy conditions, which is conducive to an increased mass flow rate and heat dissipation and, subsequently, introduces a favorable thermo-flow performance of the cooling system. When the wind speed increases, the leading flow effect of the air deflectors improves, and improvements in the ACC’s performance in the wind directions of 45° and –45° are more satisfactory. However, hot plume recirculation may impede performance when the wind direction is 0°. For all cases, air deflectors in an arc shape are recommended to restrain the disadvantageous wind effects.
Highlights
As one of the main cooling ends in the thermal power cycle, the direct dry cooling system is of great significance because of its energy-efficient operation of thermal power plants with a lack of water resources, by which the exhaust steam releases heat to ambient air via an air-cooled condenser (ACC)
Comparing the results of ACCs with arc and plane deflectors, it is not difficult to find that the air mass flow rate through the first column or row condenser cells with arc deflectors was greater than that with plane deflectors, which is coincident with the results shown in Figure 7, Figure 10, and as for the second column or row ACCs along the wind direction, the results were the opposite
Two types of air deflectors are proposed to install below the windward fans to improve the thermo-flow performances of ACCs
Summary
As one of the main cooling ends in the thermal power cycle, the direct dry cooling system is of great significance because of its energy-efficient operation of thermal power plants with a lack of water resources, by which the exhaust steam releases heat to ambient air via an air-cooled condenser (ACC). By means of numerical simulations, Gu et al [13] investigated the roof wind-proof structure effect on ACC performance in windy conditions, finding that hot plume recirculation can be reduced by a windbreak line screen. Yang et al [15] put forward three wind-proof device configurations to reduce unfavorable wind effects, and they suggested using flow leading devices below the fan platform to recover the performance of the peripheral ACCs. Zhang and Chen [16] suggested a wind-proof mesh arranged outside the fan platform bridge to improve ACC performance under windy conditions. Under windless and windy conditions in various wind directions, the ACC’s thermal-flow characteristics with and without air deflectors are numerically investigated and compared, by using the commercial software Fluent, and are compared to the results with plate air deflectors. The comparisons of results in different wind directions are developed, and the influences of air deflectors on hot air recirculation are discussed
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
