【摘要】：節(jié)能減排以及能源高效利用在當(dāng)今能源資源短缺的時(shí)代受到極高的關(guān)注,建筑能耗中的空調(diào)能耗在整個(gè)能源消耗總量中所占比重較大,故需通過(guò)先進(jìn)技術(shù)改進(jìn)或系統(tǒng)優(yōu)化等方式減小空調(diào)耗能�？諝庠礋岜檬且钥諝鉃榈推窡嵩�,吸收空氣中的熱量或冷量以達(dá)到制熱或制冷的目的高效節(jié)能換熱設(shè)備。然而在我國(guó)北方寒冷地區(qū),空氣源熱泵的使用受到限制,當(dāng)冬季室外溫度較低時(shí),由于蒸發(fā)器受低溫影響出現(xiàn)蒸發(fā)溫度較低,壓縮機(jī)排氣溫度過(guò)高,壓縮比增大等問(wèn)題而使熱泵不能正常運(yùn)行,但此時(shí)建筑內(nèi)部的熱負(fù)荷卻隨室外溫度降低而增大,以至于空調(diào)采暖能耗增大。多能源綜合利用是解決以上問(wèn)題的有效辦法,例如在空氣源熱泵的基礎(chǔ)上加以太陽(yáng)能、生物質(zhì)能等輔助換熱。本文采用一種新型太陽(yáng)能-空氣源雙熱源復(fù)合熱泵,對(duì)室外換熱器結(jié)構(gòu)進(jìn)行優(yōu)化,迎風(fēng)側(cè)第一排換熱管內(nèi)走太陽(yáng)能熱水,對(duì)進(jìn)入蒸發(fā)器的低溫空氣進(jìn)行預(yù)熱,提高蒸發(fā)器蒸發(fā)溫度。文章針對(duì)某品牌60kw-V型空氣源熱泵進(jìn)行優(yōu)化改進(jìn),首先對(duì)室外機(jī)部分流路布置進(jìn)行優(yōu)化,然后對(duì)未加太陽(yáng)能熱水的室外換熱器進(jìn)行數(shù)值模型建立,選取一層翅片作為計(jì)算單元,模擬名義工況下每臺(tái)風(fēng)機(jī)風(fēng)量以3000m3/h為步長(zhǎng),由9000m3/h增加至18000m3/h時(shí)對(duì)空氣源熱泵換熱的影響。得出不同風(fēng)機(jī)風(fēng)量下,換熱量隨風(fēng)量的增加而增加,后趨于穩(wěn)定,室外溫度較高時(shí),可采取單一熱源空氣源熱泵進(jìn)行供熱。另外風(fēng)量越大,空氣側(cè)的壓力損失越大。針對(duì)復(fù)合熱泵的復(fù)合換熱器建立數(shù)值模型,模擬室外溫度分別在名義工況(7℃)、標(biāo)準(zhǔn)工況(0℃)以及以濟(jì)南為例,冬季室外空調(diào)計(jì)算溫度(-7.7℃)三種工況下,不同風(fēng)機(jī)風(fēng)量和太陽(yáng)能熱水溫度時(shí)復(fù)合熱泵的換熱效果。太陽(yáng)能熱水以5℃為步長(zhǎng),由15℃增至30℃,風(fēng)機(jī)風(fēng)量設(shè)置同單獨(dú)空氣源熱泵風(fēng)量設(shè)置。結(jié)果表示:復(fù)合熱泵的換熱量與COP均高于未加熱水時(shí)空氣源熱泵的換熱情況,室外工況溫度越低,復(fù)合熱泵的優(yōu)勢(shì)越明顯。模擬名義工況下,名義工況下的換熱量最高出現(xiàn)在水溫30℃時(shí),為71.66kw,相比空氣源熱泵高出18.21%,但太陽(yáng)能熱水溫度30℃時(shí)蒸發(fā)器出風(fēng)溫度高于7℃,空氣被額外加熱,換熱量也隨風(fēng)機(jī)風(fēng)量的增大出現(xiàn)減小的趨勢(shì),表明30℃的水溫度偏高。標(biāo)準(zhǔn)工況下,熱水溫度25℃時(shí)蒸發(fā)器出風(fēng)溫度均高于0℃,室外空調(diào)計(jì)算溫度下,水溫20℃時(shí)的蒸發(fā)器出風(fēng)溫度接近于-7.7℃。Nu隨風(fēng)機(jī)風(fēng)量和室外溫度的降低而增大,最終認(rèn)為熱水溫度在20℃以下時(shí)較為合適。不同風(fēng)機(jī)風(fēng)量對(duì)翅片空氣側(cè)壓力損失影響較大,壓降隨速度指數(shù)增大,根據(jù)空氣源熱泵與復(fù)合熱泵空氣側(cè)壓降及阻力特性,結(jié)合對(duì)應(yīng)換熱量、COP等認(rèn)為風(fēng)量15000m3/h時(shí)較為合適,折合風(fēng)速2.07m/s。由不同工況時(shí)的蒸發(fā)器出風(fēng)溫度變化趨勢(shì)得出,室外溫度更低時(shí),可適當(dāng)調(diào)低太陽(yáng)能熱水的進(jìn)水溫度。
[Abstract]:Energy saving and emission reduction and efficient use of energy are highly concerned in the era of energy shortage. The energy consumption of air conditioning in building energy consumption accounts for a large proportion of the total energy consumption. Therefore, it is necessary to reduce the energy consumption of air conditioning by advanced technology improvement or system optimization. Air source heat pump (AHP) is a kind of high efficiency energy saving heat exchange equipment which takes air as the low quality heat source and absorbs the heat or cooling capacity in the air to achieve the purpose of heating or cooling. However, in the cold area of northern China, the use of air-source heat pump is restricted. When the outdoor temperature is low in winter, the evaporation temperature is lower and the exhaust temperature of compressor is too high because the evaporator is affected by low temperature. The heat pump can not operate normally due to the increase of compression ratio, but the heat load inside the building increases with the decrease of outdoor temperature, so that the heating energy consumption of air conditioning increases. Multi-energy comprehensive utilization is an effective way to solve the above problems, such as solar energy, biomass energy and other auxiliary heat transfer on the basis of air-source heat pump. In this paper, a new type of solar-air heat pump with two heat sources is used to optimize the structure of outdoor heat exchangers. The first row of heat exchanger tubes on the upwind side walk solar hot water to preheat the low temperature air entering the evaporator. Raise evaporator evaporation temperature. In this paper, a brand of 60kw-V air source heat pump is optimized. Firstly, the flow path of outdoor unit is optimized, and then the numerical model of outdoor heat exchanger without solar hot water is established. A layer of fin is selected as the calculation unit to simulate the effect on the heat transfer of air-source heat pump when the wind volume of each typhoon is increased from 9000m3/h to 18000m3/h with 3000m3/h as step under nominal operating conditions. The results show that the heat transfer increases with the increase of air volume and then tends to be stable. When the outdoor temperature is high, a single heat source air source heat pump can be used for heat supply. In addition, the larger the air volume, the greater the pressure loss on the air side. The numerical model of composite heat exchanger is established. The outdoor temperature is simulated under nominal (7 鈩，

本文編號(hào)：2383354