本文選題：太陽能噴射制冷　切入點(diǎn)：平板集熱發(fā)生器　出處：《河北工程大學(xué)》2015年碩士論文　論文類型：學(xué)位論文

【摘要】：隨著全球范圍內(nèi)能耗的增加和空氣的污染,能源和環(huán)境問題引起廣泛的公眾關(guān)注�？紤]到諸多因素,開發(fā)和利用太陽能是解決能源與環(huán)境問題最有效的方法之一,對(duì)于節(jié)能與環(huán)保的太陽能噴射制冷系統(tǒng)的研究已逐步成為熱點(diǎn)。本課題通過數(shù)值模擬與實(shí)驗(yàn)相結(jié)合的方法,對(duì)直接蒸發(fā)式太陽能噴射制冷系統(tǒng)進(jìn)行了研究。系統(tǒng)省卻了傳統(tǒng)太陽能制冷系統(tǒng)的發(fā)生器,制冷劑在集熱發(fā)生器內(nèi)直接吸熱蒸發(fā),不僅為噴射器提供動(dòng)力,還減少了中間換熱設(shè)備。用噴射器代替?zhèn)鹘y(tǒng)制冷系統(tǒng)的壓縮機(jī),系統(tǒng)結(jié)構(gòu)簡單、運(yùn)行維護(hù)費(fèi)用低。首先對(duì)直接蒸發(fā)式太陽能噴射制冷系統(tǒng)進(jìn)行了熱力學(xué)分析,然后分別針對(duì)太陽能集熱發(fā)生器、噴射器、蒸發(fā)器、冷凝器、膨脹閥和循環(huán)泵建立了數(shù)學(xué)模型,主要對(duì)太陽能集熱發(fā)生器和噴射器進(jìn)行了設(shè)計(jì)計(jì)算。再次基于相變理論,太陽輻照度為800W/m2、進(jìn)口速度0.047m/s、出口壓力2.65MPa工況下,對(duì)集熱發(fā)生器進(jìn)行數(shù)值模擬,研究管內(nèi)制冷劑的相變情況,分別得到了管內(nèi)含氣率和管壁溫度的變化趨勢(shì),不同管截面上的溫度變化情況�；跉怏w動(dòng)力學(xué)理論,發(fā)生溫度80℃、蒸發(fā)溫度5℃、冷凝溫度36℃工況下,確定了噴射器的結(jié)構(gòu)參數(shù)。通過數(shù)值模擬得到了噴射器內(nèi)流體的速度、壓力、溫度的變化規(guī)律,模擬表明在噴嘴出口和混合室圓柱段截面處有激波產(chǎn)生,會(huì)引起此處速度降低,壓力和溫度提高,同時(shí)也分析了結(jié)構(gòu)參數(shù)和運(yùn)行參數(shù)對(duì)噴射制冷系統(tǒng)性能的影響。結(jié)果顯示,工作壓力2.65MPa、蒸發(fā)溫度5℃、冷凝溫度36℃時(shí),噴射器的噴嘴距0mm,混合室圓柱段直徑10mm的噴射器性能最好,噴射系數(shù)能達(dá)0.32,系統(tǒng)COP達(dá)0.36。最后基于R134a搭建直接蒸發(fā)式太陽能噴射制冷系統(tǒng)實(shí)驗(yàn)臺(tái),并安裝了溫度和壓力傳感器,結(jié)合數(shù)據(jù)采集系統(tǒng),實(shí)現(xiàn)了系統(tǒng)的自動(dòng)化測(cè)試。
[Abstract]:With the increase in global energy consumption and air pollution, energy and environmental problems have attracted widespread public concern. Considering many factors, the development and utilization of solar energy is one of the most effective solutions to energy and environmental problems. The research on energy saving and environmental protection solar ejector refrigeration system has gradually become a hot spot. The direct evaporative solar energy jet refrigeration system is studied. The system eliminates the generator of the traditional solar energy refrigeration system, and the refrigerant evaporates directly in the collector, which not only provides the power for the ejector. The compressor with ejector instead of traditional refrigeration system has simple structure and low cost of operation and maintenance. Firstly, the thermodynamic analysis of direct evaporative solar energy jet refrigeration system is carried out. Then the mathematical models of solar energy collector, ejector, evaporator, condenser, expansion valve and circulating pump are established respectively. The design and calculation of solar energy collector and ejector are mainly carried out. The solar irradiance is 800W / m2, the inlet velocity is 0.047m / s, and the outlet pressure is 2.65MPa. The heat collector is numerically simulated to study the phase change of the refrigerant in the tube, and the variation trend of the gas content and the temperature of the tube wall is obtained. Based on the theory of gas dynamics, the temperature of 80 鈩，

本文編號(hào)：1568893