本文選題：高膨脹比　切入點：數(shù)值仿真　出處：《哈爾濱工業(yè)大學》2015年碩士論文

【摘要】：動力系統(tǒng)是各種航空、航天、航海設(shè)備的核心部件,動力系統(tǒng)的優(yōu)劣直接決定了飛行器、航海器等設(shè)備的各項性能。動力系統(tǒng)一般分為電動力系統(tǒng)和熱動力系統(tǒng)兩大類。電動力系統(tǒng)具有航程小、速度低、噪聲小的特點。熱動力系統(tǒng)具有功率大、燃料的能量密度高、噪聲大等特點�？紤]到熱動力系統(tǒng)功率大、航程遠的優(yōu)點,本文選用熱動力系統(tǒng),并設(shè)計了具有雙壓力級的高膨脹比渦輪。本文針對這種類型的渦輪進行了氣動設(shè)計及數(shù)值仿真。設(shè)計的雙壓力級渦輪工作在最佳速比下,達到了較高的效率及輸出功率。由于在大膨脹比渦輪中,靜葉承擔了很高的焓降,常規(guī)葉片很難滿足相應(yīng)的要求,因此,渦輪的兩級靜葉都選用了拉伐爾噴管來實現(xiàn)大焓降。為了保證渦輪動葉葉片不至于過小,采用了局部進氣的方案。在設(shè)計過程中,首先,根據(jù)基本設(shè)計參數(shù),按照選定方案,進行了渦輪的一維氣動設(shè)計,確定了基本參數(shù)。之后,對渦輪各部件進行了三維建模及對渦輪三維流場數(shù)值仿真。三維數(shù)值計算結(jié)果表明,通過的流量及輸出功率達到設(shè)計要求。同時,通過分析數(shù)值計算的結(jié)果,研究了噴管的性能參數(shù)及其內(nèi)的流動狀況,動葉流道內(nèi)的流動分離、激波的特點,局部進氣對渦輪內(nèi)氣動參數(shù)的影響及不同位置動葉葉片的載荷分布的影響。在對流場進行分析之后,利用有限元分析軟件對渦輪動葉葉片的形變、應(yīng)力進行了計算及分析,結(jié)果表明,應(yīng)力集中一般出現(xiàn)在渦輪的葉片根部。最后,設(shè)計并分析了幾種形式的渦輪出口的擴壓段的減速效果及能量損失,通過采用逐步擴張型的擴壓管,并采用波浪型的壁面,可以在較小的損失的條件下,增大出口氣流分布均勻性,并達到較好的減速效果。
[Abstract]:Power system is the core component of all kinds of aeronautical, spaceflight and navigation equipments. The merits and demerits of power system directly determine the performance of aircraft, navigator and so on.Power system is generally divided into two categories: electric power system and thermal power system.The electric power system has the characteristics of small range, low speed and low noise.Thermal power system has the characteristics of high power, high energy density of fuel, high noise and so on.Considering the advantages of large power and long range of thermal power system, this paper selects the thermal power system and designs a high expansion ratio turbine with double pressure level.In this paper, the aerodynamic design and numerical simulation of this type of turbine are carried out.The designed double pressure stage turbine works at the optimum speed ratio and achieves high efficiency and output power.Due to the high enthalpy drop of the stator blade in the turbine with large expansion ratio, it is difficult for the conventional blade to meet the corresponding requirements. Therefore, both stages of the turbine still blade adopt the Laval nozzle to realize the large enthalpy drop.In order to ensure that the turbine blade blade is not too small, a local air intake scheme is adopted.In the design process, firstly, according to the basic design parameters and the selected scheme, the one-dimensional aerodynamic design of the turbine is carried out, and the basic parameters are determined.Then, three-dimensional modeling and numerical simulation of turbine three-dimensional flow field are carried out.The three-dimensional numerical results show that the flow rate and output power meet the design requirements.At the same time, by analyzing the results of numerical calculation, the performance parameters of nozzle and its internal flow condition, the flow separation in moving vane passage and the characteristics of shock wave are studied.After the flow field is analyzed, the deformation and stress of turbine blade blade are calculated and analyzed by using finite element analysis software. The results show that the stress concentration usually occurs at the blade root of turbine.Finally, the deceleration effect and energy loss of the expansion section of several forms of turbine outlet are designed and analyzed. By adopting a gradual expansion tube and a wavy wall surface, it is possible to reduce the loss under the condition of small loss.The distribution uniformity of outlet airflow is increased, and a good deceleration effect is achieved.
【學位授予單位】：哈爾濱工業(yè)大學
【學位級別】：碩士
【學位授予年份】：2015
【分類號】：TK05

【引證文獻】

相關(guān)會議論文 前2條

1 李軍;孫皓;李彬;晏鑫;宋立明;豐鎮(zhèn)平;孫奇;鐘剛云;江生科;吳其林;王為民;;高負荷葉片和大焓降級在葉輪機械通流部分設(shè)計和優(yōu)化中應(yīng)用的研究進展[A];中國動力工程學會透平專業(yè)委員會2010年學術(shù)研討會論文集[C];2010年

2 伊進寶;錢建平;董春鵬;李留成;趙衛(wèi)兵;師海潮;;魚雷渦輪機變工況工作特性數(shù)值研究[A];2010年中國造船工程學會優(yōu)秀學術(shù)論文集[C];2011年

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本文編號：1692677