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R502-R2替代物 R404A-R502及R22替代物 ◆R22与R115按48.8:51.2混合而成 ◆R125/R143a/R134a/按4:52:4%混合 ◆主要目的是降低R22在大压比下排气温度太高 (149°C)的问题,使温度下降22-33°C,低 ◆可作为R502的替代工质适宜用在冷藏运 压升高;回热特性好,制冷量和COP都提高了 输车及集装箱制冷系统中 ◆不溶于水 ◆R404A的标准压力下泡点温度为466C 滑油溶解性差,与烷基苯 相变温度滑移较小,约为0.8℃,气化潜热 为143.48kJ/kgK,液体的比热为 ◆低温下(-40°C)回油没问题 164!J/kgK,气体的比热为1.03kJ/kgK 因含有R115而被禁用。 ODP=0. GWP=4540 R407C-R22替代物 R410A-R2替代物 ◆R32/R125/R134a按23:25:52%组成 ◆R32和R125两种工质按50:50%组成 ◆标准压力下泡点温度为-43.8℃,相变温度滑 鲁标准压力下泡点温度为5156℃,相变温度滑移 移为7.1℃。0DP=0,GwP=1980 小于02℃,近共沸混合物,热力学性能十分 ◆R407C的热力性质与R22最为相似。它们的工作 接近单工质。 压力范围,制冷量都十分相似 ●同R22相比,R410A的冷凝压力增大近50%,是 鲁原有R22机器设备改用R407C后需要更换润滑油 一种高压制冷剂,需要提高系统耐压强度。由 于R410A的高压高密度使得允许制冷剂管径减小 的制冷量和能效比比R2机器稍有下降 许多,压缩机的排量也可大大降低;同时R410A 液相的热导卑高,粘度低使其具有明显由于R22 ◆泄漏带来问题严重 的传輸特性 ◆ODP=0,GWP=2340,不可燃。 非芸沸混合工质使用特点 2,Gide in Evanorators-DX EVAP ure shows a zeotrope mixture of R-134a and R-32 where the ratio graph, the difference between the te The difference between the two lines is the temperature glides rigerant in DX evaporators are more forgivin sign, the refrigerant passes the thermal expansion device (IX valve) will boil fir followed by the other compounds. The high amount of superbe sure all the refrigerant subcomponents are boiled (converted to a gas) will be mainta11 R502-R22替代物 R22与R115按48.8:51.2混合而成。 主要目的是降低R22在大压比下排气温度太高 (149°C)的问题,使温度下降22-33 °C,低 压升高;回热特性好,制冷量和COP都提高了 不溶于水 与石腊族和环烷族润滑油溶解性差,与烷基苯 润滑油溶解性好。 低温下(-40 °C)回油没问题。 因含有R115而被禁用。 R404A -R502及R22替代物 R125/R143a/R134a/按44:52:4% 混合 可作为R502的替代工质,适宜用在冷藏运 输车及集装箱制冷系统中 R404A的标准压力下泡点温度为-46.6℃, 相变温度滑移较小,约为0.8℃,气化潜热 为143.48kJ/kg.K,液体的比热为 1.64kJ/kg.K,气体的比热为1.03kJ/kg.K。 ODP=0,GWP=4540 R407C -R22替代物 R32/R125/R134a按23:25:52% 组成 标准压力下泡点温度为-43.8℃,相变温度滑 移为 7.1℃。ODP=0,GWP=1980 R407C的热力性质与R22最为相似。它们的工作 压力范围,制冷量都十分相似 原有R22机器设备改用R407C后需要更换润滑油、 调整制冷剂的充灌量及节流元件。R407C机器 的制冷量和能效比比R22机器稍有下降。 泄漏带来问题严重 R410A -R22替代物 R32和R125两种工质按50:50% 组成 标准压力下泡点温度为-51.6℃,相变温度滑移 小于0.2℃,属近共沸混合物,热力学性能十分 接近单工质。 同R22相比,R410A的冷凝压力增大近50%,是 一种高压制冷剂,需要提高系统耐压强度。由 于R410A的高压高密度使得允许制冷剂管径减小 许多,压缩机的排量也可大大降低;同时R410A 液相的热导率高,粘度低使其具有明显由于R22 的传输特性。 ODP=0,GWP=2340,不可燃。 非共沸混合工质使用特点: 1、Temperature Glides Figure shows a zeotropic mixture of R-134a and R-32 where the ratio of R-32 is varied from 0 to 100%. By drawing a line vertically through the graph, the difference between the temperature as a liquid (lower line) and the temperature as a vapor (top line) can clearly be seen. The difference between the two lines is the temperature glides. 2,Glide in Evaporators-DX EVAP. Refrigerant in DX evaporators are more forgiving to refrigerants with glide than flooded evaporators are but as a system component, they are less efficient. Figure shows a DX evaporator. In this design, the refrigerant passes through the thermal expansion device (TX valve) and is atomized into very fine liquid droplets in the tubes of the evaporator. The fine droplets offer a large amount of surface area to absorb heat from either air or chilled water on the outside of the tubes. Zeotropic refrigerants with glide will fractionate in the tubes. The compounds with lower boiling points will boil first followed by the other compounds. The high amount of superheat used in DX evaporators will make sure all the refrigerant subcomponents are boiled (converted to a gas) and the relative mass ratios will be maintained
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