本文選題：蒸發(fā)式冷凝器 + 強(qiáng)化換熱��； 參考：《長(zhǎng)沙理工大學(xué)》2013年碩士論文

【摘要】：空調(diào)能耗是建筑能耗的重要組成部分，約占整個(gè)建筑能耗的50%左右，并有逐年增加的趨勢(shì)，因此降低空調(diào)機(jī)組的能耗是非常重要的。冷凝器是空調(diào)機(jī)組中主要的熱交換設(shè)備，其運(yùn)行特性將直接影響空調(diào)機(jī)組的性能及運(yùn)行的經(jīng)濟(jì)性，增強(qiáng)冷凝器的換熱效果，會(huì)促使整個(gè)空調(diào)機(jī)組的COP提高，從而降低空調(diào)機(jī)組的能耗。目前，冷凝器有空冷式、水冷式和蒸發(fā)式三種類(lèi)型，蒸發(fā)式冷凝器相對(duì)于其它形式的冷凝器具有換熱效率高、節(jié)水及結(jié)構(gòu)緊湊等特點(diǎn)而受到了廣泛關(guān)注，這為深入分析蒸發(fā)式冷凝器的換熱特性及合理設(shè)計(jì)提供了理論依據(jù)。 本文對(duì)蒸發(fā)式冷凝器的傳熱傳質(zhì)機(jī)理進(jìn)行了分析，建立了蒸發(fā)式冷凝器的三維物理模型，通過(guò)數(shù)值模擬研究了冷凝器結(jié)構(gòu)對(duì)蒸發(fā)式冷凝器換熱性能的影響以及冷凝器溫度場(chǎng)和速度場(chǎng)的分布規(guī)律，并對(duì)其結(jié)構(gòu)進(jìn)行優(yōu)化，從而得出以下結(jié)論： （1）在同種條件下，圓形截面噴嘴的換熱性能優(yōu)于方形截面噴嘴； （2）當(dāng)噴嘴間距為100mm～200mm和管束區(qū)管間距為12mm～28mm時(shí)，通過(guò)對(duì)噴淋水速度、噴淋水溫度與換熱量關(guān)系的研究，得出當(dāng)噴淋水速度為1.8m/s、噴淋水溫度為30℃時(shí)，換熱量達(dá)到最大值； （3）通過(guò)對(duì)冷凝器溫度場(chǎng)、速度場(chǎng)和換熱量的模擬研究，得出當(dāng)噴嘴間距為200mm、噴淋水速度為1.8m/s、噴淋水溫度為30℃、噴嘴到管束區(qū)首排管束距離為200mm、管束區(qū)管間距為16mm時(shí)，溫度場(chǎng)和速度場(chǎng)分布都比較理想，此時(shí)換熱效果較好，單位面積換熱量為92.36kW/m2； （4）利用軟件中DPM模型分析了在上述情況下的液滴分布規(guī)律，得到當(dāng)噴嘴間距為200mm、噴嘴到管束區(qū)首排管束距離為200mm、管束區(qū)管間距為16mm時(shí)，液滴可以較好的均勻覆蓋在換熱盤(pán)管的表面，，說(shuō)明此種情況下蒸發(fā)換熱效果較好。
[Abstract]:Air conditioning energy consumption is an important part of building energy consumption, about 50% of the total building energy consumption, and has a trend of increasing year by year, so it is very important to reduce the energy consumption of air conditioning units. Condenser is the main heat exchange equipment in the air conditioning unit. Its operation characteristics will directly affect the performance and operation economy of the air conditioning unit, enhance the heat transfer effect of the condenser, and promote the cop of the whole air conditioning unit. Thus, the energy consumption of the air conditioning unit is reduced. At present, there are three types of condensers: air-cooled, water-cooled and evaporative. The evaporative condenser has been widely concerned because of its high heat transfer efficiency, water saving and compact structure. This provides a theoretical basis for in-depth analysis of heat transfer characteristics and rational design of evaporative condensers. In this paper, the heat and mass transfer mechanism of evaporative condenser is analyzed, and the three-dimensional physical model of evaporative condenser is established. The influence of condenser structure on the heat transfer performance of evaporative condenser and the distribution of temperature field and velocity field of condenser were studied by numerical simulation, and its structure was optimized. The conclusions are as follows: (1) under the same conditions, the heat transfer performance of circular section nozzle is better than that of square section nozzle, (2) when the nozzle spacing is 100mm~200mm and the tube spacing of tube bundle is 12mm~28mm, Through the study of the relationship between spray water velocity, spray water temperature and heat transfer, the maximum heat transfer is obtained when the spray water velocity is 1.8 m / s and the spray water temperature is 30 鈩

本文編號(hào)：2065073