【摘要】：在一定的飛行條件和氣象條件下,航空發(fā)動(dòng)機(jī)的進(jìn)氣部件,如進(jìn)氣道、風(fēng)扇葉片、支板、旋轉(zhuǎn)帽罩等會(huì)出現(xiàn)結(jié)冰現(xiàn)象。如果冰層快速增加,減小進(jìn)氣道氣流流通的截面積,導(dǎo)致航空發(fā)動(dòng)機(jī)性能惡化。旋轉(zhuǎn)帽罩結(jié)冰嚴(yán)重時(shí),直接會(huì)增加旋轉(zhuǎn)帽罩的重量,增大發(fā)動(dòng)機(jī)負(fù)荷,會(huì)使發(fā)動(dòng)機(jī)不能正常工作。如果發(fā)生冰脫落,甚至?xí)＜鞍l(fā)動(dòng)機(jī)的安全。所以,為了防止帽罩結(jié)冰,必須對(duì)帽罩進(jìn)行防冰處理。與熱氣防冰、憎水涂層防冰等方式相比,旋轉(zhuǎn)熱管防冰具有獨(dú)特的優(yōu)勢(shì)。但目前對(duì)旋轉(zhuǎn)熱管內(nèi)部工質(zhì)流動(dòng)和傳熱機(jī)理認(rèn)識(shí)仍不十分清楚,有待進(jìn)一步研究。為了揭示旋轉(zhuǎn)熱管內(nèi)部工質(zhì)的復(fù)雜流動(dòng)和準(zhǔn)確描述旋轉(zhuǎn)熱管內(nèi)部工質(zhì)流動(dòng)和傳熱特性,本文采用VOF多相流模型,將液體和蒸氣作為一個(gè)整體的區(qū)域,建立基于完整Navier-Stokes方程組的二維數(shù)學(xué)模型,以揭示更多的細(xì)節(jié)特征和旋轉(zhuǎn)熱管內(nèi)部流動(dòng)和傳熱特性規(guī)律。本文采用CFD軟件結(jié)合氣液界面追蹤程序和導(dǎo)熱定律的界面相變模型,對(duì)軸向旋轉(zhuǎn)熱管內(nèi)部工質(zhì)流動(dòng)和傳熱特性進(jìn)行了數(shù)值模擬研究。分別研究了純導(dǎo)熱蒸發(fā)模型和考慮自然對(duì)流的蒸發(fā)模型,并和實(shí)驗(yàn)結(jié)果進(jìn)行了對(duì)比,以探索相變模型的優(yōu)劣。采用了考慮自然對(duì)流的相變模型,分析了傳熱量、充液量、轉(zhuǎn)速和工質(zhì)等參數(shù)對(duì)旋轉(zhuǎn)熱管流動(dòng)和傳熱特性的影響規(guī)律。研究表明:蒸發(fā)段采用純導(dǎo)熱蒸發(fā)模型,其數(shù)值模擬結(jié)果和實(shí)驗(yàn)值誤差較大。考慮自然對(duì)流的相變模型,其數(shù)值模擬結(jié)果和實(shí)驗(yàn)值吻合很好,驗(yàn)證了該模型的可靠性和準(zhǔn)確性。傳熱量對(duì)傳熱性能影響較小;轉(zhuǎn)速越高,傳熱性能越強(qiáng);充液量對(duì)傳熱性能影響較小,這和文獻(xiàn)中的實(shí)驗(yàn)結(jié)論一致;工質(zhì)的物性參數(shù)對(duì)旋轉(zhuǎn)熱管傳熱性能影響顯著。全錐度旋轉(zhuǎn)熱管和典型旋轉(zhuǎn)熱管具有相似的工作特性。和典型旋轉(zhuǎn)熱管相比,全錐度旋轉(zhuǎn)熱管具有更好的傳熱性能和其冷凝段具有更好的均溫性�；谥暗男D(zhuǎn)熱管研究工作,采用了考慮自然對(duì)流的相變模型,對(duì)旋轉(zhuǎn)帽罩熱管防冰裝置進(jìn)行了防冰性能的數(shù)值模擬研究。研究發(fā)現(xiàn),熱載荷對(duì)整個(gè)裝置的傳熱性能影響較小,防冰熱載荷對(duì)帽罩表面均溫性有影響;轉(zhuǎn)速越高,傳熱性能越強(qiáng),轉(zhuǎn)速對(duì)帽罩表面均溫性影響較小;導(dǎo)熱材料的導(dǎo)熱系數(shù)越大,帽罩表面均溫性越好。另外,在防冰工況下,潤(rùn)滑油和環(huán)境溫差在100℃以上,而維持帽罩表面溫度在結(jié)冰溫度以上時(shí),蒸發(fā)段和帽罩表面溫差遠(yuǎn)遠(yuǎn)低于這個(gè)值,表明以潤(rùn)滑油作為熱源的旋轉(zhuǎn)熱管具有帽罩防冰的可行性。本文形成了基于數(shù)值計(jì)算的旋轉(zhuǎn)帽罩熱管防冰裝置的設(shè)計(jì)方法,可以用來(lái)研究不同結(jié)構(gòu)、不同工作參數(shù)對(duì)其影響規(guī)律,大大減少了人力、物力和財(cái)力,從而為工程設(shè)計(jì)提供了支持和指導(dǎo)。
[Abstract]:Under certain flight and weather conditions, the aero-engine intake components, such as intake ports, fan blades, branch plates, rotating cap covers and so on, will freeze. If the ice layer increases rapidly, the cross section of inlet airflow will be reduced, which will result in the deterioration of aero-engine performance. When the rotation cap freezes seriously, it will directly increase the weight of the rotating cap cover and increase the engine load, which will make the engine unable to work properly. If ice comes off, it will even endanger the safety of the engine. Therefore, in order to prevent the cap from freezing, the cap must be ice-proof treatment. Compared with hot air ice protection and hydrophobic coating, rotating heat pipe has unique advantages. However, the mechanism of fluid flow and heat transfer in rotating heat pipe is still unclear, which needs further study. In order to reveal the complex flow of the working fluid in the rotating heat pipe and accurately describe the flow and heat transfer characteristics of the working fluid in the rotating heat pipe, a VOF multiphase flow model is used in this paper, in which the liquid and steam are regarded as a whole region. A two-dimensional mathematical model based on holonomic Navier-Stokes equations was established to reveal more detailed characteristics and the characteristics of flow and heat transfer in rotating heat pipe. In this paper, the fluid flow and heat transfer characteristics in axial rotating heat pipe are numerically simulated by using CFD software combined with the gas-liquid interface tracing program and the interfacial phase transition model of heat conduction law. The pure heat conduction evaporation model and the evaporation model considering natural convection are studied, and the results are compared with the experimental results to explore the advantages and disadvantages of the phase transition model. A phase transition model considering natural convection is used to analyze the influence of heat transfer rate, liquid charge, rotational speed and working fluid on the flow and heat transfer characteristics of rotating heat pipe. The results show that the numerical simulation results of the evaporative section with pure heat conduction evaporation model are quite different from the experimental data. The numerical simulation results are in good agreement with the experimental data, and the reliability and accuracy of the model are verified. The effect of heat transfer quantity on heat transfer performance is small; the higher the rotational speed, the stronger the heat transfer performance; the smaller the effect of liquid charge on heat transfer performance, which is consistent with the experimental results in literature; and the significant effect of the physical parameters of working fluid on the heat transfer performance of rotating heat pipe. The full taper rotary heat pipe and the typical rotary heat pipe have similar working characteristics. Compared with the typical rotary heat pipe, the full taper rotating heat pipe has better heat transfer performance and better uniform temperature in the condensation section. Based on the previous research work of rotating heat pipe, a phase change model considering natural convection was used to simulate the anti-ice performance of the heat pipe with rotating cap cover. It is found that the heat load has little effect on the heat transfer performance of the whole device, the anti-ice thermal load has an effect on the uniform temperature of the cap cover surface, and the higher the rotational speed, the stronger the heat transfer performance, and the less the effect of the speed on the uniform temperature property of the cap cover surface. The larger the coefficient of thermal conductivity is, the better the average temperature of the cap is. In addition, when the temperature difference between lubricating oil and ambient temperature is above 100 鈩，

本文編號(hào)：2130430