本文選題：直接空冷機(jī)組　切入點：風(fēng)機(jī)群　出處：《北京交通大學(xué)》2011年碩士論文　論文類型：學(xué)位論文

【摘要】：直接空冷風(fēng)機(jī)運行情況對整個凝汽器的換熱效果起著決定性作用。本文基于充分利用軸流風(fēng)機(jī)的調(diào)頻功能,通過數(shù)值模擬方法研究風(fēng)機(jī)群并聯(lián)運行規(guī)律,研究結(jié)果可以為電廠實現(xiàn)風(fēng)機(jī)單機(jī)或局部調(diào)控提供一定參考,并為改善直接空冷凝汽器的換熱能力和減少風(fēng)機(jī)耗電量提供基礎(chǔ)數(shù)據(jù)。 首先分析了在有、無風(fēng)環(huán)境下,空冷風(fēng)機(jī)群并聯(lián)運行時動力學(xué)特性。研究結(jié)果表明：無風(fēng)時中間風(fēng)機(jī)進(jìn)風(fēng)量較多,而且各風(fēng)機(jī)的容積效率差距較小,約為0.968～0.98；有風(fēng)時各風(fēng)機(jī)容積效率差距較大,約為0.55～0.93,有風(fēng)時風(fēng)機(jī)進(jìn)風(fēng)溫度比無風(fēng)時高。 在有風(fēng)群抽規(guī)律的基礎(chǔ)上,進(jìn)一步分析環(huán)境因素對風(fēng)機(jī)群運行特性的影響。主要研究環(huán)境風(fēng)速、風(fēng)向和風(fēng)溫等對風(fēng)機(jī)群運行規(guī)律的影響。研究結(jié)果表明：隨著風(fēng)速提高,各風(fēng)機(jī)容積效率不斷降低,靠近來流的風(fēng)機(jī)下降幅度更大,最大可達(dá)到風(fēng)速每增加1m/s,容積效率約下降0.13；隨風(fēng)向角增大,風(fēng)機(jī)總進(jìn)風(fēng)量先減小后增多,在45°時最少。分析了加裝不同形狀擋風(fēng)墻、導(dǎo)流板和擋板時風(fēng)機(jī)群并聯(lián)運行特性。研究結(jié)果表明：加裝曲面擋風(fēng)墻時,靠近來流的風(fēng)機(jī)容積效率都提高；擋風(fēng)墻全凹時不僅可以增加風(fēng)機(jī)進(jìn)風(fēng)量,而且減小風(fēng)機(jī)進(jìn)風(fēng)溫度；沿來流方向后排單元間加裝擋板,風(fēng)機(jī)總的進(jìn)風(fēng)量比未加擋板時多增加11m3/s；加裝導(dǎo)流裝置后,各風(fēng)機(jī)的容積效率均增大,最多增加7%,隨著導(dǎo)流裝置與風(fēng)機(jī)平面距離的增加,各風(fēng)機(jī)進(jìn)風(fēng)量會增加,但增加幅度越來越小 通過正交試驗法分析風(fēng)速、擋風(fēng)墻形狀、導(dǎo)流板和擋板綜合作用時,各因素影響的主次關(guān)系,得出低風(fēng)速下,加內(nèi)凹擋風(fēng)墻,沿來流方向后排單元間加擋板,在風(fēng)機(jī)平面4m處加導(dǎo)流裝置,更有利于風(fēng)機(jī)吸風(fēng)。 本文研究結(jié)果對電廠空冷島設(shè)計和風(fēng)機(jī)運行調(diào)節(jié)具有一定的指導(dǎo)意義。
[Abstract]:The operation of the direct air cooler plays a decisive role in the heat transfer effect of the whole condenser. Based on the full use of the frequency modulation function of the axial fan, the parallel operation law of the fan group is studied by numerical simulation. The results can provide some reference for the realization of single or local control of fan in power plant, and provide basic data for improving the heat transfer capacity of direct air-cooled condenser and reducing fan power consumption. Firstly, the dynamic characteristics of air-cooled air turbine cluster in parallel operation are analyzed in the presence and absence of wind. The results show that the air intake of the intermediate fan is more and the volume efficiency difference of each fan is small when there is no air. The volume efficiency of each fan has a large difference, about 0.55 ~ 0.93, and the inlet air temperature of the fan with wind is higher than that with no wind. On the basis of the extraction law of wind group, the influence of environmental factors on the operating characteristics of fan group is further analyzed. The effects of environmental wind speed, wind direction and wind temperature on the operation law of fan group are studied. The results show that: with the increase of wind speed, The volume efficiency of each fan decreases continuously, and the fan close to the incoming flow decreases by a greater extent, with the maximum wind speed increasing by 1 m / s, the volume efficiency decreases by about 0.13. With the increase of the wind direction angle, the total air intake volume of the fan decreases first and then increases. At the minimum of 45 擄, the parallel operation characteristics of wind turbines with different shapes, baffles and baffles are analyzed. The results show that the volume efficiency of the fan near to the flow is improved when the curved windshield is installed. When the windshield wall is fully concave, it can not only increase the air intake rate of the fan, but also reduce the inlet air temperature of the fan. When the air intake rate of the fan is increased by 11 m3 / s, the total air intake rate of the fan is increased by 11 m3 / s compared with that without the baffle. After the installation of the flow guide device, The volume efficiency of each fan is increased, and the maximum increase is 7. With the increase of the distance between the diversion device and the fan plane, the air volume of each fan will increase, but the increase will be smaller and smaller. Through the orthogonal test method, the main and secondary relationships of the factors affecting the wind speed, the shape of the windshield wall, the guide plate and the baffle are analyzed, and the conclusion is drawn that under the low wind speed, the inner concave windshield wall is added, and the baffle is added to the back row units along the direction of the incoming flow. It is more advantageous for the fan to absorb air by adding the diversion device at the plane of 4 m. The results of this paper have certain guiding significance for the design of air cooling island and the regulation of fan operation in power plant.
【學(xué)位授予單位】：北京交通大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2011
【分類號】：TH432.1

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 馬義偉;;發(fā)電廠空冷技術(shù)的現(xiàn)狀與進(jìn)展[J];電力設(shè)備;2006年03期

2 趙文升;王松嶺;高月芬;崔凝;;直接空冷系統(tǒng)中熱風(fēng)回流現(xiàn)象的數(shù)值模擬和分析[J];動力工程;2007年04期

3 周蘭欣;白中華;張淑俠;王統(tǒng)彬;;空冷平臺外部流場的數(shù)值模擬[J];動力工程;2008年03期

4 周蘭欣;李建波;李衛(wèi)華;田亞釗;;直接空冷機(jī)組凝汽器加裝下?lián)躏L(fēng)墻的數(shù)值模擬[J];動力工程;2008年05期

5 王佩璋;;1000MW空冷汽輪機(jī)組的工程實施問題[J];發(fā)電設(shè)備;2007年06期

6 楊杰,孫剛;基于MATLAB和Visual C++的風(fēng)機(jī)流場分析的可視化研究[J];風(fēng)機(jī)技術(shù);2005年05期

7 李欣,鄧斌,陶文銓;翅片管束式管殼式換熱器三維數(shù)值模擬研究[J];工程熱物理學(xué)報;2005年02期

8 楊立軍;杜小澤;楊勇平;;風(fēng)機(jī)群分區(qū)調(diào)節(jié)對空冷島傳熱特性的影響[J];工程熱物理學(xué)報;2010年01期

9 趙之東,楊豐利;直接空冷凝汽器的發(fā)展和現(xiàn)狀[J];華北電力技術(shù);2004年05期

10 李海宏;;600MW空冷機(jī)組風(fēng)機(jī)運行研究[J];東北電力技術(shù);2010年05期

相關(guān)碩士學(xué)位論文 前5條

1 胡漢波;直接空冷式凝汽器翅片散熱器流動傳熱性能及單元流場特性研究[D];重慶大學(xué);2006年

2 周文平;火電廠直接空冷平臺的數(shù)值模擬[D];重慶大學(xué);2007年

3 周捷;寧夏靈武2×600MW直接空冷系統(tǒng)優(yōu)化研究[D];華北電力大學(xué)（河北）;2007年

4 賈寶榮;空冷凝汽器空氣流動傳熱特性的數(shù)值模擬[D];華北電力大學(xué)（北京）;2009年

5 周敬博;直接空冷機(jī)組噴淋系統(tǒng)優(yōu)化運行及單元中空氣流動傳熱特性研究[D];北京交通大學(xué);2010年

，

本文編號：1608874