空氣源二氧化碳熱泵熱水器的優(yōu)化設計
發(fā)布時間:2018-07-16 23:46
【摘要】:隨著空氣源二氧化碳熱泵熱水器的不斷發(fā)展,熱泵熱水器也開始在我國逐步應用。由于二氧化碳熱泵熱水器應用于商業(yè)或者是工業(yè)上更具有經(jīng)濟性優(yōu)勢,因此本文就根據(jù)GB/T21362--2008《商業(yè)或工業(yè)用及類似用途的熱泵熱水機》規(guī)定的測試工況,對制冷劑充注量、水的質(zhì)量流量等影響因素進行了實驗,實驗結(jié)果表明: (1)C02熱泵熱水系統(tǒng)存在最佳C02充注量,充注過少,通過壓縮機和蒸發(fā)器的制冷劑流量較小,造成設備浪費,同時所得熱水溫度過低;充注過多會使操作壓力過大,降低系統(tǒng)COP。本文確定了最佳C02充注量為8MPa。 (2)水的質(zhì)量流量對COP和出口水溫的影響是相反的,增大水的流量會增加COP,但會降低出口水溫,需綜合考慮系統(tǒng)對于COP和熱水水溫的要求來確定最佳流量。 (3)本文通過實驗確定了在CO2充注量為8MPa,水流量為800ml/min、壓縮機排氣壓力為8.5MPa時能夠滿足GB/T21362—2008的要求。 在實驗的基礎之上,對空氣源C02熱泵熱水器進行了(?)分析,建立了壓縮機等系統(tǒng)各部件的(?)分析模型,計算了各個部件的(?)損失和系統(tǒng)的(?)效率。經(jīng)過計算發(fā)現(xiàn),系統(tǒng)的(?)效率只有27.7%,系統(tǒng)(?)效率較低。同時比較各個部件的(?)損失發(fā)現(xiàn),壓縮機的炯損失所占總的(?)損失的百分比最大,其次是節(jié)流閥,然后是氣體冷卻器,蒸發(fā)器最小。而且壓縮機和節(jié)流閥處的(?)損失相差不大,相比較而言,對于節(jié)流設備的優(yōu)化改進不管是從可行性還是經(jīng)濟性上來說都更具優(yōu)勢,因此本文決定利用噴射器來代替節(jié)流閥作為節(jié)流設備。 設計了應用于空氣源二氧化碳熱泵熱水器的噴射器,對噴射器的設計方法、噴射系數(shù)、噴射器的結(jié)構(gòu)尺寸等進行了詳細的介紹,并利用Visual Basic對噴射器的設計計算過程進行了程序設計,經(jīng)過計算,噴射器可達到的最大噴射系數(shù)為0.7。 采用數(shù)值模擬的方法對噴射器的內(nèi)部流場進行了分析。計算得到的噴射系數(shù)與理論計算的誤差為11.4%。分析了噴射器內(nèi)部的速度場和壓力場,同時還對工作流體壓力、引射流體壓力等工作參數(shù)對超臨界C02噴射器的性能影響進行了分析,分析發(fā)現(xiàn),提高混合流體壓力會降低噴射系數(shù),在確定噴射器設計參數(shù)時,應該兼顧噴射系數(shù)和混合流體出口壓力的關(guān)系,適當降低升壓比(Pc/Ph),可以提高噴射器可達到的最大引射能力。
[Abstract]:With the development of air-source carbon dioxide heat pump water heater, heat pump water heater is gradually applied in our country. Since CO2 heat pump water heaters are more economical in commercial or industrial applications, the refrigerant is charged according to the test conditions specified in GB/ T21362--2008 for commercial or industrial heat pump water heaters. The experimental results show that: (1) the optimal charge of CO2 exists in the C02 heat pump hot water system, and the flow rate of refrigerant through compressor and evaporator is small, which results in waste of equipment. At the same time, the temperature of the obtained hot water is too low, too much filling will make the operating pressure too large, and reduce the system COP. In this paper, it is determined that the optimal charge of CO2 is 8 MPA. (2) the effect of water mass flow on cop and outlet water temperature is opposite. Increasing the water flow will increase COP, but decrease the outlet water temperature. The optimal flow rate should be determined by considering the cop and the water temperature of hot water. (3) the experiment results show that the system can meet the requirements of GB / T21362-2008 when the CO _ 2 charge is 8MPa, the water flow is 800ml / min, and the compressor exhaust pressure is 8.5MPa. Based on the experiment, the air source heat pump water heater C02 has been carried out. Analysis and establishment of compressor and other components of the system (?) By analyzing the model, the (?) Loss and system (?) Efficiency. After calculation, it is found that the system's (?) Efficiency is only 27. 7%, system (?) Low efficiency. At the same time, compare the (?) Losses are found to account for the total loss of compressors (?) The percentage loss is highest, followed by throttle valves, then gas coolers, and evaporators the smallest. And compressor and throttle place (?) The loss is not different, compared to the throttling equipment, the optimization and improvement of the throttling equipment is more advantageous in terms of feasibility and economy, so this paper decides to use the ejector instead of the throttle valve as the throttling equipment. The ejector used in air source carbon dioxide heat pump water heater is designed. The design method, ejector coefficient and structure size of ejector are introduced in detail. The design and calculation process of the ejector is programmed by Visual basic, and the maximum ejector coefficient is 0.7. The internal flow field of the ejector is analyzed by numerical simulation. The error between the calculated injection coefficient and the theoretical calculation is 11.4. The velocity field and pressure field inside the ejector are analyzed. The influence of working fluid pressure and ejection fluid pressure on the performance of supercritical C02 injector is also analyzed. When the ejector design parameters are determined, the relationship between the ejection coefficient and the outlet pressure of the mixed fluid should be taken into account, and the maximum ejection capacity of the ejector can be improved by properly reducing the pressure boost ratio (Pc / Ph).
【學位授予單位】:大連理工大學
【學位級別】:碩士
【學位授予年份】:2014
【分類號】:TU822
本文編號:2128095
[Abstract]:With the development of air-source carbon dioxide heat pump water heater, heat pump water heater is gradually applied in our country. Since CO2 heat pump water heaters are more economical in commercial or industrial applications, the refrigerant is charged according to the test conditions specified in GB/ T21362--2008 for commercial or industrial heat pump water heaters. The experimental results show that: (1) the optimal charge of CO2 exists in the C02 heat pump hot water system, and the flow rate of refrigerant through compressor and evaporator is small, which results in waste of equipment. At the same time, the temperature of the obtained hot water is too low, too much filling will make the operating pressure too large, and reduce the system COP. In this paper, it is determined that the optimal charge of CO2 is 8 MPA. (2) the effect of water mass flow on cop and outlet water temperature is opposite. Increasing the water flow will increase COP, but decrease the outlet water temperature. The optimal flow rate should be determined by considering the cop and the water temperature of hot water. (3) the experiment results show that the system can meet the requirements of GB / T21362-2008 when the CO _ 2 charge is 8MPa, the water flow is 800ml / min, and the compressor exhaust pressure is 8.5MPa. Based on the experiment, the air source heat pump water heater C02 has been carried out. Analysis and establishment of compressor and other components of the system (?) By analyzing the model, the (?) Loss and system (?) Efficiency. After calculation, it is found that the system's (?) Efficiency is only 27. 7%, system (?) Low efficiency. At the same time, compare the (?) Losses are found to account for the total loss of compressors (?) The percentage loss is highest, followed by throttle valves, then gas coolers, and evaporators the smallest. And compressor and throttle place (?) The loss is not different, compared to the throttling equipment, the optimization and improvement of the throttling equipment is more advantageous in terms of feasibility and economy, so this paper decides to use the ejector instead of the throttle valve as the throttling equipment. The ejector used in air source carbon dioxide heat pump water heater is designed. The design method, ejector coefficient and structure size of ejector are introduced in detail. The design and calculation process of the ejector is programmed by Visual basic, and the maximum ejector coefficient is 0.7. The internal flow field of the ejector is analyzed by numerical simulation. The error between the calculated injection coefficient and the theoretical calculation is 11.4. The velocity field and pressure field inside the ejector are analyzed. The influence of working fluid pressure and ejection fluid pressure on the performance of supercritical C02 injector is also analyzed. When the ejector design parameters are determined, the relationship between the ejection coefficient and the outlet pressure of the mixed fluid should be taken into account, and the maximum ejection capacity of the ejector can be improved by properly reducing the pressure boost ratio (Pc / Ph).
【學位授予單位】:大連理工大學
【學位級別】:碩士
【學位授予年份】:2014
【分類號】:TU822
【參考文獻】
相關(guān)期刊論文 前10條
1 汪南;朱冬生;;家用熱泵熱水器的研究及發(fā)展趨勢[J];日用電器;2006年11期
2 王玉軍,劉軍,顧小剛;空氣源熱泵熱水機綜合技術(shù)分析[J];中國建設信息(供熱制冷?);2005年11期
3 李嫵,陶文銓,,康海軍,李惠珍,辛榮昌;整體式翅片管換熱器傳熱和阻力性能的試驗研究[J];機械工程學報;1997年01期
4 史暢;當前國內(nèi)熱水器市場現(xiàn)狀與趨勢分析[J];家電科技;2003年05期
5 管海清 ,馬一太 ,楊俊蘭;日本家用CO_2熱泵熱水器研究開發(fā)現(xiàn)狀分析[J];家電科技;2004年06期
6 羅清海,湯廣發(fā),龔光彩,唐海兵;建筑熱水節(jié)能途徑分析[J];煤氣與熱力;2004年06期
7 王侃宏,王景剛,侯立泉,馬一太,魏東,洪芳軍;CO_2跨臨界水——水熱泵循環(huán)系統(tǒng)的實驗研究[J];暖通空調(diào);2001年03期
8 王如竹;吳靜怡;許煜雄;;高效節(jié)電的空氣能熱泵熱水器[J];上海電力;2004年06期
9 劉寶明,何家雄,夏斌,張樹林;國內(nèi)外CO_2研究現(xiàn)狀及發(fā)展趨勢[J];天然氣地球科學;2004年04期
10 姜云濤;馬一太;劉和成;張鵬;;帶回熱器的高效跨臨界CO_2水-水熱泵的實驗研究[J];天津大學學報;2010年04期
本文編號:2128095
本文鏈接:http://www.sikaile.net/guanlilunwen/chengjian/2128095.html
教材專著