【摘要】：直膨式新風(fēng)機(jī)采用表面式蒸發(fā)器處理新風(fēng),處理后空氣的含濕量較低,可滿(mǎn)足絕大多數(shù)情況下溫濕度獨(dú)立控制系統(tǒng)對(duì)新風(fēng)含濕量處理的要求。但直膨式新風(fēng)機(jī)的負(fù)荷卸載和低負(fù)荷時(shí)系統(tǒng)的穩(wěn)定性等問(wèn)題制約了其應(yīng)用。在全年工況下,室外新風(fēng)溫度和含濕量變化較大,工況負(fù)荷相差很大。探索使直膨式新風(fēng)機(jī)既滿(mǎn)足高溫、高濕工況下的除濕降溫要求,又能在低負(fù)荷工況下穩(wěn)定高效運(yùn)行的方法對(duì)促進(jìn)直膨式新風(fēng)機(jī)廣泛應(yīng)用具有重要意義。本文先設(shè)計(jì)了一種雙級(jí)直膨式新風(fēng)機(jī),兩級(jí)獨(dú)立制冷并利用二級(jí)系統(tǒng)冷凝器調(diào)節(jié)送風(fēng)溫度。然后通過(guò)實(shí)驗(yàn)研究了不同因素對(duì)該新風(fēng)機(jī)性能的影響和該新風(fēng)機(jī)在廣州地區(qū)極濕工況和空調(diào)期工況的運(yùn)行性能。首先,本文研究了進(jìn)口空氣干球溫度、濕球溫度和中間溫度(一級(jí)蒸發(fā)器出風(fēng)溫度)對(duì)該雙級(jí)直膨式新風(fēng)機(jī)性能的影響。實(shí)驗(yàn)結(jié)果表明:因一級(jí)制冷系統(tǒng)容量為二級(jí)制冷系統(tǒng)容量的3.4倍,所以一級(jí)系統(tǒng)的性能對(duì)新風(fēng)機(jī)整體性能影響非常大。新風(fēng)機(jī)進(jìn)口干、濕球溫度和中間溫度對(duì)一級(jí)制冷系統(tǒng)和新風(fēng)機(jī)整體性能影響的規(guī)律基本一致。在干球溫度實(shí)驗(yàn)工況下,新風(fēng)機(jī)進(jìn)口干球溫度對(duì)制冷量、顯熱比、輸入功率、Energy Efficiency Ratio(EER)、再熱量和送風(fēng)含濕量影響較小。除濕量、顯熱量和潛熱量受干球溫度影響較大。濕球溫度為25℃時(shí),干球溫度每升高3℃,除濕量平均減小0.87g/s,平均減幅為14.6%;顯熱量平均增大3.08kW,平均增幅為16.8%;潛熱量平均減小2.15kW,平均減幅為14.3%。在濕球溫度實(shí)驗(yàn)工況下,新風(fēng)機(jī)進(jìn)口濕球溫度對(duì)制冷量、顯熱量、顯熱比、EER、再熱量和送風(fēng)含濕量影響較小。除濕量、潛熱量和輸入功率受濕球溫度影響較大。風(fēng)量為3000m3/h時(shí),濕球溫度每升高1℃,除濕量平均增大1.19g/s,平均增幅為21.4%;潛熱量平均增大2.99kW,平均增幅為21.2%;輸入功率平均增大1.07kW,平均增幅為12.2%。在中間溫度實(shí)驗(yàn)工況下,中間溫度對(duì)新風(fēng)機(jī)各性能參數(shù)的影響均比較大,其中最為突出的是輸入功率、再熱量和送風(fēng)含濕量。風(fēng)量為3000m3/h時(shí),中間溫度每升高2℃,輸入功率平均減小3.18kW,平均減幅為28.2%;再熱量平均減小3.65kW,平均減幅為31.3%;送風(fēng)含濕量平均增加2.09g/kg干空氣,平均增幅為37.5%。其次,本文研究了該雙級(jí)直膨式新風(fēng)機(jī)在廣州地區(qū)極濕工況和空調(diào)期工況的運(yùn)行性能。極濕實(shí)驗(yàn)工況下,新風(fēng)機(jī)運(yùn)行風(fēng)量為2000m3/h,中間溫度14℃,送風(fēng)溫度22℃。該雙級(jí)直膨式新風(fēng)機(jī)的EER在2.32~2.62之間,送風(fēng)含濕量在7.92~8.55g/kg干空氣之間。因測(cè)試平臺(tái)加熱和加濕能力的限制,空調(diào)期工況實(shí)驗(yàn)分為兩部分,低焓值段風(fēng)量為3000m3/h,高焓值段風(fēng)量為1000m3/h。低焓值段時(shí)該新風(fēng)機(jī)EER在3.45~4.16之間,送風(fēng)含濕量在7.74~8.01g/kg干空氣之間;高焓值段時(shí)該新風(fēng)機(jī)EER在3.09~3.46之間,送風(fēng)含濕量在8.92~9.14g/kg干空氣之間。相同風(fēng)量時(shí),該新風(fēng)機(jī)EER和送風(fēng)含濕量均隨進(jìn)口空氣焓值升高而增大。
[Abstract]:The surface evaporator is used to deal with the fresh air. The moisture content of the air after treatment is low, which can meet the requirements of the independent control system of temperature and humidity in most cases for the treatment of the moisture content of the fresh air. However, the problems of load unloading and system stability at low load limit its application. The outdoor fresh air temperature and moisture content change greatly in the whole year, and the load of outdoor fresh air varies greatly. It is of great significance to explore the method that can not only satisfy the requirements of dehumidification and cooling under high temperature and high humidity conditions, but also can operate stably and efficiently under low load conditions, in order to promote the wide application of direct expansion new fans. In this paper, a two-stage direct-expansion new fan is designed, two-stage independent refrigeration and two-stage system condenser are used to adjust the air supply temperature. Then the effects of different factors on the performance of the new fan and the performance of the new fan under extremely wet and air conditioning conditions in Guangzhou are studied experimentally. Firstly, the effects of inlet air dry bulb temperature, wet bulb temperature and intermediate temperature (outlet air temperature of the first-stage evaporator) on the performance of the two-stage direct-expansion new fan are studied in this paper. The experimental results show that because the capacity of the first stage refrigeration system is 3.4 times that of the second stage refrigeration system, the performance of the first stage system has a great influence on the overall performance of the new fan. The effects of dry inlet wet bulb temperature and intermediate temperature on the whole performance of the first stage refrigeration system and the new fan are basically consistent. Under the experimental condition of dry bulb temperature, the inlet dry bulb temperature of the new fan has little effect on the cooling capacity, sensible heat ratio, the input power, Energy Efficiency Ratio (EER), reheat and the moisture content of the air supply. The dehumidification, apparent heat and latent heat are greatly affected by dry bulb temperature. When the wet bulb temperature is 25 鈩，

本文編號(hào)：2457403