Weak current College】 【air-conditioning-section IV-air conditioning-Power By】 【China power house network.

<br> This section is for refrigeration systems, refrigeration equipment, frozen water (refrigerant) pipeline and cooling water (htm) pipeline, three of the circulatory system. Small air conditioner not cold and heat medium pipeline, the direct use of fan forced air .flow instead of refrigerant and htm cycle is the most simple refrigeration system. In learning to master various refrigeration principle and refrigerator with three child components of the circulatory system. 1. refrigeration unit refrigeration unit is at the core of the refrigeration system, common refrigerator with .compression refrigerating, absorption chillers, etc. 1. compression refrigerating compression refrigerating liquid vaporization heat absorbing way refrigeration. It consists of a compressor, condenser, thermostatic expansion valve, evaporator and other parts, four pipe connections between devices to form a closed system. < .br> Refrigerants, refrigeration and heat-exchange medium, temperature changes as described in the following procedure. <br> Compressor will evaporator generated low temperature and low pressure of the refrigerant gas suction hood, the compressor compressed into a high temperature, high pressure of .the gas is discharged to the condenser. Htm is responsible for the condenser heat away in refrigerants, common htm is the cooling water or air. Refrigerant and htm in the condenser inside the heat exchanger. Therefore, before entering the condenser htm is at room temperature ., came out from the condenser is the temperature of the refrigerant into the condenser; the former is a high temperature, high pressure of gas, came out from the condenser is liquid at normal temperature and high pressure. <br> Compressor will evaporator of cylinder .gas inhalation, and flows into the condenser. Therefore, the evaporator at low pressure condition. Refrigerant through the expansion valve throttle down into evaporator, at low pressure condition and immediately vaporization, while absorbing the evaporator heat around the refrigerant, commonly used refrigerants is frozen .water or air conditioners. Therefore, the refrigerant into the evaporator is at room temperature before, came out from the evaporator is low; refrigerants in before entering the evaporator is at room temperature and low pressure of the liquid, came out from the evaporator is a .low temperature and low pressure of gas. <br> Refrigerant into the expansion valve throttle is high-pressure liquid; from the expansion valve is low after cutting out of the liquid, temperature changes. Before entering the compressor and refrigerant is low temperature and low .pressure of gas; came out from the compressor is a high temperature, high pressure of the gas. Refrigerant by the high temperature, low temperature and room temperature to high temperature, complete a cycle. When the lines form a continuous loop, you can provide .a steady source of cold and heat. 2. absorption chiller absorption chiller to LIBR aqueous solution as refrigerants, with water as refrigerant, lithium bromide solution as the absorbent. It leverages LIBR aqueous solution at room temperature (especially at low temperature) the ability to .absorb water vapour, and at high temperatures and moisture is absorbed by the release of characteristics of, and access to water at low pressure refrigerant evaporates to absorb the surrounding medium heat characteristics for refrigeration purposes. <br> Water evaporation temperature and pressure, the lower .the pressure, the more prone to boiling water. In absorption refrigeration, water as refrigerant in the refrigeration cycle is in high vacuum, which is the absorption characteristics of the work. <br> Absorption chillers and compression refrigerating cycle, htm and refrigerant cycle is .exactly the same, the difference is in the refrigeration cycle, came out from the evaporator temperature and low pressure steam becomes high temperature and high pressure steam before entering the condenser, the existence of a cycle of LIBR aqueous solution. In this loop, LIBR aqueous .solution first absorption of water vapor in the absorber into low temperature and low pressure, low concentration of State, then pump to the generator, the work becomes steam heating, high temperature, high pressure, and water vapour separation into the condenser, LIBR aqueous solution .concentration from low to high. Therefore, the generator has two products: one will enter the condenser, the formation of refrigerant cycle of high temperature and high pressure steam; another is the pressure regulating valve into the absorber, the formation of LIBR aqueous solution cycle .of high temperature, high pressure and high concentration of LIBR aqueous solution. LIBR aqueous solution by low temperature and low pressure, low concentration State to a high temperature, high pressure, high concentration of State non-stop cycle while it travels by water vapour at .low temperature and low pressure state to a high temperature and high pressure conditions. Therefore, LIBR aqueous solution of circulation and compressor features identical to the low temperature and low pressure of the refrigerant gas into a high temperature, high pressure of the refrigerant gases. < .br> But the mechanism of different needs, absorption chiller produces steam heat absorption outside complete refrigeration, also need to complete all pump drive. While the compression refrigerator just compressor power can complete refrigeration and cyclic process. Therefore, the absorption chiller of piping rather complex .on vacuum requirements is relatively high, but it can use around the heat source, and its advantages. Second, frozen water system of frozen water system is responsible for the preparation of refrigerating plants to the chilled water air handling equipment, generally can be divided into .a closed system and open system. Third, the cooling water system of cooling water is responsible for the absorption of the refrigerant vapor condensation during heat and heat into the room. It generally can be divided into DC, hybrid and revolving, etc. <br .>.