【摘要】：開發(fā)新型高性能空間推進(jìn)系統(tǒng)是目前各國學(xué)者研究的重點,也是未來空間推進(jìn)的主要發(fā)展方向。二硝酰胺銨(ADN)基單組元液體推進(jìn)劑是目前具有廣闊應(yīng)用前景的綠色空間推進(jìn)劑,由于其具有的優(yōu)良性能,可以取代姿軌控發(fā)動機上所廣泛應(yīng)用的肼類推進(jìn)劑。而高效組織ADN基推進(jìn)劑的霧化、蒸發(fā)、催化分解和燃燒等過程,對提高推力器比沖性能,可靠性以及經(jīng)濟(jì)性等具有重要的意義。本文以高性能ADN基推力器為研究背景,以綠色無毒ADN基空間推進(jìn)劑為工質(zhì),通過實驗方法獲得了 ADN基推進(jìn)劑的旋流霧化特性,并采用數(shù)值模擬方法獲得了 ADN基推力器三維仿真計算結(jié)果,探討了推進(jìn)劑組分配比變動的影響。同時明確了推力器關(guān)鍵參數(shù)對ADN基推力器內(nèi)催化分解和燃燒過程的影響機理,為小量級航天推力器的設(shè)計以及推力器內(nèi)部霧化燃燒機理的進(jìn)一步研究提供支持。建立了 ADN基推進(jìn)劑旋流霧化特性研究的實驗裝置。其中,基于最大流量原理的經(jīng)驗系數(shù)方法,設(shè)計了旋流噴嘴。采用高速攝影和馬爾文粒度儀相結(jié)合的方法分別獲得了旋流噴霧動態(tài)圖像以及液滴粒徑分布信息。研究了 ADN基單組元推進(jìn)劑的旋流霧化特性,通過對旋流噴霧形態(tài)進(jìn)行分析,明確了推進(jìn)劑旋流霧化過程中的發(fā)展和演化特性,探討了噴射壓力,噴孔結(jié)構(gòu)參數(shù),切向孔結(jié)構(gòu)參數(shù)以及旋流室結(jié)構(gòu)參數(shù)對旋流霧化中宏觀和微觀特性的影響規(guī)律,獲得了噴射參數(shù)和噴嘴結(jié)構(gòu)參數(shù)對液膜破碎長度,霧化錐角以及平均粒徑的影響規(guī)律。結(jié)果表明,提高噴射壓力,降低噴嘴長度,降低噴嘴直徑,增加旋流室高度,增加切向孔數(shù)量都有利于ADN基推進(jìn)劑霧化特性的提高,并獲得了切向孔孔數(shù)和旋流室直徑的優(yōu)值。明確了噴嘴結(jié)構(gòu)參數(shù)對旋流霧化特性的影響權(quán)重,明確了旋流室直徑和高度分別是影響噴霧錐角和液膜破碎長度的關(guān)鍵因素,而切向孔數(shù)量是影響液滴平均粒徑大小的關(guān)鍵因素。從而進(jìn)一步揭示了噴嘴結(jié)構(gòu)參數(shù)對ADN基推進(jìn)劑旋流霧化過程中宏觀和微觀特性的影響規(guī)律。以ADN基單組元推力器為研究對象,耦合基于噴嘴霧化特性實驗結(jié)果的旋流霧化模型,以及蒸發(fā)模型,多孔介質(zhì)傳質(zhì)模型,考慮熱彌散效應(yīng)的多孔介質(zhì)非等溫傳熱模型,輻射模型以及簡化化學(xué)反應(yīng)動力學(xué)模型等,建立了 ADN基推力器的物理和數(shù)學(xué)模型。其中,液滴蒸發(fā)速率預(yù)測模型通過實驗獲得。首先,基于差式掃描量熱法,獲得了 ADN基推進(jìn)劑催化分解過程中的吸放熱特性。研究了非觸壁態(tài)的液滴蒸發(fā)過程,探討了液滴與高溫壁面接觸后的形態(tài)變化,明確了液滴在不同壁面溫度條件下的生存時間,獲得了 ADN基推進(jìn)劑液滴與石英玻璃之間的萊頓弗洛斯特現(xiàn)象,明確了高低溫條件下液滴蒸發(fā)的階段特征,最終建立了ADN基推進(jìn)劑液滴蒸發(fā)速率的理論預(yù)測模型。根據(jù)所建立的ADN基推力器催化分解和燃燒的物理數(shù)學(xué)模型,通過數(shù)值模擬方法研究了推力器內(nèi)溫度的空間分布特性,探討了沿推力器中心軸線以及催化床出口截面和燃燒室出口截面的組分分布特性,明確了 ADN基推力器內(nèi)溫度分布,以及反應(yīng)物ADN,甲醇,重要中間產(chǎn)物AN,N2O,NO2,HCOOH,以及生成物CO2,H2O等組分之間的相互關(guān)系,揭示了催化分解和燃燒反應(yīng)在推力器內(nèi)不同位置處的反應(yīng)程度。同時,明確了 ADN基推進(jìn)劑組分配比變動對推力器內(nèi)溫度空間分布和物質(zhì)組分分布的差異性,獲得了使得推力器比沖性能提高的推進(jìn)劑組分配比的最優(yōu)值。最后研究了推力器關(guān)鍵參數(shù),包括催化床運行參數(shù),噴射壓力和推力器結(jié)構(gòu)參數(shù),對ADN基推力器催化分解和燃燒過程的影響機理。探討了不同工況下,溫度的空間分布,反應(yīng)物以及重要中間產(chǎn)物在催化床和燃燒室出口截面軸線處組分分布特性,明確了推力器關(guān)鍵參數(shù)對催化分解和燃燒反應(yīng)區(qū)域的影響機制。結(jié)果表明,孔隙率的增加,預(yù)熱溫度的升高,噴射壓力的增加都有利于推力器比沖性能的提高,同時明確了預(yù)熱溫度為420K條件下推力器的啟動特性,獲得了催化床長度和推力器直徑的最優(yōu)值。明確了推力器關(guān)鍵參數(shù)對ADN基推力器比沖性能的影響權(quán)重,明確了推力器直徑是比沖性能影響的主導(dǎo)因素,而催化床孔隙率對比沖性能的影響相對較小。為ADN基推力器的設(shè)計和點火實驗的研究提供了幫助。
[Abstract]:The development of a new high-performance space propulsion system is the focus of the research of national scholars, and is also the main direction of development of space propulsion in the future. The ADN-based single-group liquid propellant is a green space propellant with wide application prospect. The process of atomization, evaporation, catalytic decomposition and combustion of ADN-based propellant is of great significance to improve the performance, reliability and economy of the ADN-based propellant. In this paper, the swirl atomization characteristics of ADN-based propellant are obtained by using the high-performance ADN-based solid propellant as the research background, and the simulation results of ADN-based propellant are obtained by means of numerical simulation. The influence of distribution ratio variation of propellant group was discussed. At the same time, the influence mechanism of critical parameters on the catalytic decomposition and combustion process in ADN-based diesel engine is clarified, and the support is provided for the design of small-scale space combustion engine and the further research on the mechanism of internal atomization combustion. An experimental apparatus for the study of swirl atomization characteristics of ADN-based propellant is established. The swirl nozzle is designed based on the empirical coefficient method based on the maximum flow principle. The dynamic image of swirl spray and the distribution of droplet size were obtained by combining high speed photography and Malvern particle size instrument. The swirl atomization characteristics of the ADN-based single-group propellant are studied. Through the analysis of the swirl spray morphology, the development and evolution characteristics of the propellant swirl atomization process are clarified, and the injection pressure and orifice structure parameters are discussed. The influence of the parameters of tangential hole and the structural parameters of swirl chamber on the macroscopic and microscopic characteristics of swirl atomization is studied. The influence of spray parameters and nozzle structure parameters on the fracture length, atomizing cone angle and average particle size of liquid film are obtained. The results show that increasing the injection pressure, reducing nozzle length, reducing nozzle diameter, increasing swirl chamber height, increasing the number of tangential holes is favorable to the improvement of atomization characteristics of ADN-based propellant, and obtains excellent value of tangential hole number and swirl chamber diameter. The influence weight of nozzle structure parameters on the characteristics of swirl atomization is defined. The diameter and height of swirl chamber are the key factors that influence the fracture length of spray cone and liquid film, and the number of tangential holes is the key factor that affects the average particle size of the droplet. The influence of nozzle structure parameters on the macroscopic and microscopic characteristics of ADN-based propellant swirl atomization is further revealed. Taking the ADN-based single-group element as the research object, the swirl atomization model based on the experimental results of the nozzle atomization characteristics, and the evaporation model, the mass transfer model of the porous medium, the non-isothermal heat transfer model of the porous medium considering the heat dispersion effect, The physical and mathematical models of ADN-based magnetometer have been established by radiation model and simplified chemical reaction dynamics model. wherein the droplet evaporation rate prediction model is obtained by experiments. Firstly, the heat absorption characteristics of ADN-based propellant catalytic decomposition are obtained based on the differential scanning calorimetry. In this paper, the droplet evaporation process of the non-contact wall state is studied, the morphology change after contact with the high temperature wall surface is discussed, the survival time of the liquid drops under different wall temperature conditions is clarified, and the Leiden Frost phenomenon between the droplets of the ADN-based propellant and the quartz glass is obtained. The phase characteristics of droplet evaporation under high and low temperature conditions are clarified, and the theoretical prediction model of droplet evaporation rate of ADN-based propellant is finally established. Based on the established physical mathematical model of the catalytic decomposition and combustion of ADN-based hydrogen cyanide, the spatial distribution characteristics of the temperature in the combustion chamber are studied by numerical simulation method, and the distribution characteristics of the components along the central axis and the outlet cross section of the catalytic bed and the outlet cross section of the combustion chamber are discussed. The relationship between the temperature distribution in the ADN base and the components of the reactant ADN, methanol, an important intermediate product AN, N2O, NO2, HCOOH, and the product CO2, H2O and the like are clarified, and the reaction degree of the catalytic decomposition and the combustion reaction at different positions in the muffle furnace is disclosed. At the same time, the difference between the distribution of the distribution ratio of the ADN-based propellant group and the distribution of the distribution of the material components in the propellant group was clarified, and the optimal value of the distribution ratio of the propellant group was obtained. Finally, the key parameters, including catalytic bed operating parameters, injection pressure and thermodynamic structure parameters, were studied, and the mechanism of the catalytic decomposition and combustion process of ADN-based hydrogen cyanide was studied. In this paper, the distribution characteristics of temperature distribution, reactant and important intermediate products in different working conditions are discussed, and the influence mechanism of critical parameters on catalytic decomposition and combustion reaction zone is defined. The results show that the increase of the porosity, the increase of the preheating temperature and the increase of the injection pressure are beneficial to the improvement of the catalytic oxidation ratio, and meanwhile, the start-up characteristic of the ingot under the condition of the preheating temperature of 420K is clarified, and the optimum value of the length of the catalytic bed and the cylinder diameter is obtained. The influence weight of critical parameters on the performance of ADN-based anti-impact ratio is clarified, and the dominant factor which is influenced by the impact on the ratio of the catalytic bed porosity is clarified, and the influence of the catalytic bed porosity on the impact resistance is relatively small. Help is provided for the design of the ADN-based magnetometer and for the study of ignition experiments.
【學(xué)位授予單位】：北京交通大學(xué)
【學(xué)位級別】：博士
【學(xué)位授予年份】：2017
【分類號】：V511

【參考文獻(xiàn)】

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1 景李s，

本文編號：2310078