本文選題：雙級壓縮　切入點：熱泵　出處：《大連理工大學》2013年博士論文

【摘要】：中間噴射特征的雙級壓縮技術(shù),可有效地改善蒸氣壓縮裝置的低溫適應(yīng)性。然而,當此技術(shù)與空氣源熱泵結(jié)合時,為滿足一系列低溫工況,系統(tǒng)中兩臺壓縮機容量配比及耦合關(guān)系將發(fā)生變化,在實際設(shè)備運行時常出現(xiàn)控制不穩(wěn)定和壓縮機燒毀等現(xiàn)象。為此,本文為完備雙級壓縮熱泵技術(shù),增強其實用性,針對變工況時雙級壓縮熱泵系統(tǒng)中壓縮機容量配比關(guān)系、壓縮機耦合特性以及中間噴射特征參數(shù)對系統(tǒng)性能影響進行了研究。 首先,基于理論循環(huán)分析,綜合制熱性能、可控性和安全穩(wěn)定性等因素,確定了R410A為本研究系統(tǒng)的循環(huán)工質(zhì)；得出一級節(jié)流中間不完全冷卻循環(huán)是雙級壓縮熱泵系統(tǒng)最適宜推廣的循環(huán)方式。依據(jù)此理論循環(huán)分析結(jié)果,搭建了可調(diào)節(jié)噴射特征參數(shù)的變?nèi)萘侩p級壓縮熱泵實驗臺。其特征在于系統(tǒng)采用了變頻壓縮機和電子膨脹閥設(shè)備,且可實現(xiàn)多變工況時系統(tǒng)宏觀性能參數(shù)的測量。 其次,基于轉(zhuǎn)子式壓縮機結(jié)構(gòu)特征,提出了雙級壓縮系統(tǒng)運行模式劃分方法。進而,構(gòu)建了反映中間壓力形成過程的變?nèi)萘侩p級壓縮系統(tǒng)壓縮機動態(tài)耦合模型以及具有中間噴射特征的雙級壓縮熱泵系統(tǒng)仿真模型,并利用實驗結(jié)果對模型進行了驗證。 第三,通過對系統(tǒng)變工況制熱性能的研究,定量分析了可調(diào)節(jié)參數(shù)對系統(tǒng)性能的影響。在蒸發(fā)溫度為-30～0℃,冷凝溫度為35～50℃,低高壓級壓縮機理論輸氣量比ε在1.13～5.08范圍時,系統(tǒng)制熱量隨著ε的增加而顯著增大,其制熱COPhot變化量可達到04左右。而噴射過程可促使系統(tǒng)制熱量提高8%-15%,系統(tǒng)制熱COPhot曾加5%～12%。 第四,基于仿真模型,并結(jié)合熱力學狀態(tài)圖,詮釋了具有耦合特性的雙級壓縮中各個過程及其輸氣量比和噴射特征參數(shù)對系統(tǒng)的影響。揭示了雙級壓縮系統(tǒng)具有低高壓級壓縮機不同步性、排氣過程間歇性、壓縮過程不連續(xù)性以及系統(tǒng)級間參數(shù)具有脈動的特征。以中間換熱器為耦合條件的噴射量和噴射工質(zhì)比焓,對級間參數(shù)產(chǎn)生較大影響,其噴射工質(zhì)比焓是噴射過程影響工質(zhì)狀態(tài)變化的定性因素,而噴射量是噴射過程影響工質(zhì)狀態(tài)變化的定量因素；當噴射量增大時,中間混合過程將由一種穩(wěn)定的“等壓混合”過程經(jīng)變質(zhì)量“等容混合”過程的過渡,最終穩(wěn)定到新的壓力升高的“等壓混合”過程。 最后,基于模擬和實驗結(jié)果,分析了中間壓力與系統(tǒng)制熱性能參數(shù)的變化規(guī)律。指出中間壓力對制熱量影響具有敏感性而對制熱性能系數(shù)影響具有弱鈍化性的特征。以制熱量、制熱性能系數(shù)(?)效率最大化為原則對系統(tǒng)調(diào)節(jié)參數(shù)進行了優(yōu)選,得到本研究系統(tǒng)在冷凝溫度40℃,蒸發(fā)溫度-30～0℃的變工況范圍運行時,中間壓力比特征參數(shù)取值為1.1～1.3、低高壓級壓縮機理論輸氣量比取值為1.3～3.2、相對噴射量取值為0.1～0.3、高壓級壓縮機吸氣過熱度取值為10℃～20℃,這些取值是最適宜的運行參數(shù)調(diào)節(jié)范圍。
[Abstract]:In order to meet a series of low - temperature working conditions , when combined with an air - source heat pump , the ratio of capacity and coupling of two compressors in the system will change . In this paper , a complete double - stage compression heat pump technology is developed to enhance its practicability .

Firstly , based on the factors such as theoretical cycle analysis , comprehensive heating performance , controllability and safety stability , the cycle working quality of the system is determined .
Based on the theoretical cycle analysis results , a variable capacity double stage compression heat pump bench with adjustable injection characteristic parameters is set up , which is characterized in that the system adopts a variable frequency compressor and an electronic expansion valve device , and can realize the measurement of the macroscopic performance parameters of the system when the multi - variable working condition is realized .

Secondly , based on the characteristics of the rotor compressor , a method for dividing the operating modes of the two - stage compression system is presented . Furthermore , the dynamic coupling model of the variable capacity double - stage compression system and the simulation model of the double - stage compression heat pump system with the intermediate injection characteristics are constructed , and the model is verified by the experimental results .

Thirdly , the influence of the adjustable parameters on the system performance is analyzed quantitatively by studying the heating performance of the system under variable working conditions . When the evaporation temperature is -30 ~ 0 鈩，

本文編號：1686341