本文關(guān)鍵詞： 閉式熱源塔 TRNSYS 模擬分析 運行特性 數(shù)值計算　出處：《湖南大學(xué)》2015年碩士論文　論文類型：學(xué)位論文

【摘要】：目前,可再生能源技術(shù)是降低采暖制冷能耗成本的關(guān)鍵措施之一。閉式熱源塔熱泵技術(shù)是一種通過輸入少量高位能源,利用熱源塔吸收空氣中的熱量,或向空氣中釋放熱量,將低品位能源向高品位轉(zhuǎn)移的新型、節(jié)能、環(huán)保的可再生能源技術(shù),實現(xiàn)了建筑物冷暖空調(diào)終端無鍋爐、無排碳、無電輔和高能效的目標(biāo)。隨著熱源塔熱泵技術(shù)的推廣,其實際工程應(yīng)用中暴露的問題也越來越多,為了熱源塔熱泵技術(shù)的發(fā)展,亟需對該技術(shù)進行必要的理論研究。本文首先根據(jù)傳熱學(xué)和熱質(zhì)交換原理,建立濕空氣物性參數(shù)和閉式熱源塔干工況、半干半濕工況、濕工況、噴淋工況的數(shù)學(xué)描述,并編譯熱源塔理論計算模型和濕空氣物性參數(shù)計算模型。其次搭建閉式熱源塔熱泵系統(tǒng)實驗裝置,對整個系統(tǒng)的運行系統(tǒng)進行全面的監(jiān)測記錄,包括熱源塔進出口溶液溫度、溶液流量、空氣溫濕度、風(fēng)機功率,水源熱泵的進出口溫度等,根據(jù)實驗測量值對理論計算模擬值進行對比分析,驗證模型的可靠性,并利用實驗數(shù)據(jù)擬合噴淋工況下閉式熱源塔空氣對流換熱系數(shù)的關(guān)聯(lián)式以及室外空氣溫度與載熱流體進口溫度的關(guān)系表達式。最后采用MATLAB和TRNSYS聯(lián)合仿真的方式對實驗臺閉式熱源塔傳熱特性進行了研究。研究結(jié)果表明,所建立的閉式熱源塔計算模塊精確度較高,可以用于閉式熱源塔熱泵系統(tǒng)的模擬分析。在噴淋條件下、閉式熱源塔內(nèi),從翅片換熱器頂部至底部,空氣焓值近似呈線性變化;對載熱流體而言,翅片換熱器上半部分換熱強度比下半部分高。噴淋溶液溫度最低處位于塔的中部位置,結(jié)霜現(xiàn)象最先從這里開始;為了保證實驗臺閉式熱源塔熱泵系統(tǒng)穩(wěn)定正常運行,選取噴淋溶液的冰點必須低于-8.4℃,載熱流體的冰點必須低于-12.7℃;在整個制熱期間,熱源塔空氣側(cè)的傳熱溫差與載熱流體側(cè)近似相等,且大部分時間處于2~3℃之間;當(dāng)空氣溫度低于5℃,相對濕度高于56.8%時,閉式熱源塔熱泵系統(tǒng)必須開啟噴淋泵,否則將會出現(xiàn)結(jié)霜運行現(xiàn)象,不利于系統(tǒng)的正常運行;在整個制熱期間,熱源塔全熱換熱量為12305k W,顯熱換熱量為8390k W,潛熱換熱量占全熱換熱量的31.8%,雖然熱源塔吸熱量以顯熱為主,但是潛熱換熱不容忽視。
[Abstract]:At present, renewable energy technology is one of the key measures to reduce the energy cost of heating and refrigeration. The new, energy-saving and environmentally friendly renewable energy technology, which transfers low grade energy to high grade, has realized the goals of no boiler, no carbon emission, no power auxiliary and high energy efficiency at the end of building cold and warm air conditioning. With the popularization of heat source tower heat pump technology, In order to develop the heat source tower heat pump technology, it is necessary to carry out the necessary theoretical research. Firstly, according to the principles of heat transfer and mass exchange, The mathematical description of the physical properties of wet air and the dry condition of closed heat source tower, the half dry and half wet condition, the wet condition and the sprinkling condition are established. The theoretical calculation model of heat source tower and the calculation model of physical parameters of wet air are compiled. Secondly, the experimental device of closed heat source tower heat pump system is built, and the whole system operation system is monitored and recorded comprehensively, including the temperature of the inlet and outlet solution of the heat source tower. The flow rate of solution, air temperature and humidity, fan power, inlet and outlet temperature of water source heat pump are compared and analyzed according to the experimental measurement value to verify the reliability of the model. The correlation expression of convection heat transfer coefficient of closed heat source tower and the relation between outdoor air temperature and inlet temperature of heat carrying fluid are fitted by experimental data. Finally, the simulation of air convection in closed heat source tower by MATLAB and TRNSYS is carried out. The heat transfer characteristics of the closed heat source tower are studied. The results show that, The calculation module of the closed heat source tower is accurate and can be used to simulate and analyze the heat pump system of the closed heat source tower. Under the spray condition, the air enthalpy changes approximately linearly from the top to the bottom of the finned heat exchanger in the closed heat source tower. For heat transfer fluid, the heat transfer intensity of the upper part of finned heat exchanger is higher than that of the lower part. The lowest temperature of spray solution is located in the middle of the tower. In order to ensure the stable and normal operation of the closed heat source tower heat pump system, the freezing point of spray solution must be lower than -8.4 鈩，

本文編號：1525076