本文選題：離心壓氣機(jī)　切入點(diǎn)：擴(kuò)壓器　出處：《大連理工大學(xué)》2011年碩士論文　論文類型：學(xué)位論文

【摘要】：微型燃機(jī)以其高效、靈活、可靠、體積小等優(yōu)點(diǎn),除了廣泛應(yīng)用于分布式發(fā)電外,還可用于備用電站、熱電聯(lián)產(chǎn)、并網(wǎng)發(fā)電、尖峰負(fù)荷發(fā)電等,無論對中心城市還是遠(yuǎn)郊農(nóng)村甚至邊遠(yuǎn)地區(qū)均能適用。此外,微型燃?xì)廨啓C(jī)在民用交通運(yùn)輸(混合動力汽車)以及軍車以及陸海邊防方面均具有優(yōu)勢。 作為微型燃機(jī)的重要組成部件之一的離心壓氣機(jī),其性能的好壞直接關(guān)系到微型燃機(jī)的效率高低。為進(jìn)一步提高WD095型微型燃機(jī)離心壓氣機(jī)的性能,本文對不同結(jié)構(gòu)形式的擴(kuò)壓器內(nèi)部流動進(jìn)行了全面和深入的數(shù)值研究,以期通過研究探索與葉輪和蝸殼更為匹配的擴(kuò)壓器結(jié)構(gòu)。 本文利用商用透平機(jī)械CFD軟件NUMECA,首先對單列葉柵擴(kuò)壓器子午流道的漸縮程度進(jìn)行了系統(tǒng)研究,通過對比發(fā)現(xiàn),對本文研究的微型離心壓氣機(jī)而言,擴(kuò)壓器出口與進(jìn)口寬度的寬度比為0.5-0.7時(shí),葉輪與擴(kuò)壓器連算結(jié)構(gòu)內(nèi)部的流動效果相對最好,性能相對最優(yōu)。 其次,本文針對擴(kuò)壓器串列葉柵第1列葉片出口角的大小對性能的影響進(jìn)行了深入研究。研究發(fā)現(xiàn)：當(dāng)?shù)?列葉片出口角為31.5。時(shí),由于第1列葉片出口與第2列葉片進(jìn)口徑向連接區(qū)域形成漸縮型通道,因此擴(kuò)壓器的擴(kuò)壓速度比最小,多變效率、壓比和總壓恢復(fù)系數(shù)都達(dá)到最高。 最后,在上述研究基礎(chǔ)上,本文對帶等寬子午流道擴(kuò)壓器的離心壓氣機(jī)在設(shè)計(jì)轉(zhuǎn)速下的全工況特性進(jìn)行了數(shù)值研究,獲得了全工況特性曲線,反映出該離心壓氣機(jī)在設(shè)計(jì)轉(zhuǎn)速下具有較為平穩(wěn)的特性,但高效區(qū)不夠?qū)�。在設(shè)計(jì)工況下計(jì)算對比了帶等寬子午流道與帶漸縮子午流道擴(kuò)壓器的整機(jī)性能,發(fā)現(xiàn)帶漸縮流道擴(kuò)壓器的離心壓氣機(jī)整機(jī)性能明顯優(yōu)于帶等寬流道擴(kuò)壓器的離心壓氣機(jī),其多變效率相對提高了2.9%,總壓比也相對提高了1.85%。通過對設(shè)計(jì)工況下帶串列葉柵擴(kuò)壓器的整機(jī)性能的研究發(fā)現(xiàn),當(dāng)?shù)?列葉片偏向第2列葉片吸力面時(shí),離心壓氣機(jī)性能更優(yōu),且出口角為31.5。時(shí),流動效果較其他結(jié)構(gòu)最好。
[Abstract]:Because of its advantages of high efficiency, flexibility, reliability and small size, micro gas turbine can be widely used in distributed power generation, as well as in standby power stations, cogeneration of heat and power, grid-connected power generation, peak load generation, etc. In addition, micro gas turbines have advantages in civil transportation (hybrid electric vehicles), military vehicles and land and sea border defense. As one of the important components of micro gas turbine, the performance of centrifugal compressor is directly related to the efficiency of micro gas turbine. In this paper, the internal flow of diffuser with different structure forms is studied comprehensively and deeply in order to explore the diffuser structure which is more suitable to the impeller and volute. In this paper, the commercial turbine machinery CFD software NUMECA is used to systematically study the degree of meridional channel shrinkage of a single-row cascade diffuser. Through comparison, it is found that, for the miniature centrifugal compressor studied in this paper, When the width ratio of outlet to inlet width of diffuser is 0.5-0.7, the flow effect of impeller and diffuser is the best and the performance is the best. Secondly, the effect of the outlet angle of the first row blade in the cascade cascade of diffuser on the performance is studied in depth. It is found that when the outlet angle of the first row blade is 31.5. Since the radial connection between the outlet of the first row and the inlet of the second row of blades forms a tapered channel, the diffuser has the highest diffuser speed ratio, variable efficiency, pressure ratio and total pressure recovery coefficient. Finally, on the basis of the above research, the full working condition characteristic of centrifugal compressor with equal width meridional passage diffuser under the design speed is studied numerically, and the whole working condition characteristic curve is obtained. The results show that the centrifugal compressor has stable characteristics at the design speed, but the high efficiency zone is not wide enough. The performance of the diffuser with equal width meridian passage and with tapered meridian passage is calculated and compared under the design conditions. It is found that the whole performance of centrifugal compressor with tapered diffuser is obviously superior to that of centrifugal compressor with equal width diffuser. The variable efficiency is improved by 2.9 and the total pressure ratio by 1.85. By studying the performance of the whole machine with cascade diffuser in the design condition, it is found that the centrifugal compressor performance is better when the first row blade is inclined to the second row blade suction surface. When the outlet angle is 31.5, the flow effect is better than that of other structures.
【學(xué)位授予單位】：大連理工大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2011
【分類號】：TH452

【引證文獻(xiàn)】

相關(guān)碩士學(xué)位論文 前1條

1 唐輝;匹配旋轉(zhuǎn)沖壓壓縮轉(zhuǎn)子的離心壓氣機(jī)氣動設(shè)計(jì)[D];大連海事大學(xué);2013年

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本文編號：1577875