Thermocreation

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Numerical design (Mathematical modelling) of a compressor for refrigeration and air conditioning(cylinder volume calculation)

Compressor is the heart of any refrigerating equipment as it pump the refrigerant in to the all components like our heart supply the blood throughout the body parts. Compressor decide the cooling capacity and power consumption for refrigerating machine. Its main work is to take the refrigerant from suction pipe at very low pressure(temperature as well) and compress it to a very high pressure (discharge pressure). As we all know that refrigerant condense in condenser at constant temperature (for zeotropic blends it vary), and that temperature is corresponding to the discharge pressure of refrigerant. Discharge pressure of refrigerant is such that its corresponding temperature should be higher than the ambient temperature only than refrigerant will condense in to liquid if the discharge saturation temperature(corresponding to discharge pressure) is lower than the ambient temperature, than refrigerant will not condense. All compressors can be described on their application(use) as...

Numerical designing (Mathematical modelling) of an air conditioner ( by two methods)

Human do not feel comfort at high temperatures or extremely low temperatures. The situation of body when it feel comfort with the surrounding conditions like temperature, RH%, air flow etc is called the thermal comfort. This comfort situation is at 27 DBT and 19 WBT. To provide this thermal comfort condition, Air conditioners are used which supply the air at required temperatures. The schematic of an air conditioner is shown as below: Consider a 1 TR air conditioner with ambient 35 DBT and 24 WBT and indoor design conditions are 27 DBT and 19 WBT . So the inlet air to evaporator is at 27 DBT and 19 WBT. The design conditions are as per below: Outdoor conditions: 35 DBT, 24 WBT Indoor conditions: 27 DBT and 19 WBT Evaporator temperature in: 12 deg C Evaporator temperature out: 15 deg C Condensing temperature: 54 deg C Liquid temperature: 46 deg C (ASHRAE conditions) Now main thing to calculate is required mass flow rate of air (CFM) and air out condi...

Methods of increasing the suction temperature to improve the Refrigeration cycle

As it is prohibited to allow liquid refrigerant to enter into compressor because of non compressible nature of refrigerants which can cause serious damage to the compressor, it is necessary to fully evaporate the refrigerant before entering in to compressor. This can be done by several ways which are listed below: 1. super heating of refrigerant at the outlet of refrigerant by using Thermal expansion valve. (used in air-conditioning). 2. By doing liquid suction heat exchanger (in domestic and commercial refrigerator). 3. By doing capillary suction heat exchanger. (In refrigerators) Let's discussed these one by one. Super heating of refrigerant in the evaporator itself: The air conditioners are used to provide thermal comfort to human being or machin...

Pressure Enthalpy chart

Pressure Enthalpy Chart It is a chart used to explain and analyze refrigeration and air conditioning systems. It consist of pressure on ordinate axis and enthalpy on abscissa. Before explaining the pressure enthalpy chart(shown in fig) lets discuss about some common terms that will be used. Pressure lines: Pressure lines originated from vertical axis (y-axis) and are horizontal lines drawn parallel to abscissa (x-axis). (light blue line in fig) Enthalpy lines: Enthalpy lines originated from horizontal axis and are vertical lines drawn parallel to vertical axis(Y-axis). (Red color in fig) Critical point: Critical point separate the saturated liquid and saturated vapor curve. Critical temperature: Critical temperature is the temperature above which the vapor can never be liquefied at any pressure. to liquefied vapor, temperature must be reduced. Critical Pressure: It is the pressure above which the vapor can never be liquefied at any tempe...

Evaporative cooling

Evaporative cooling is the basic of mostly all refrigeration technology that involve a phase change in refrigerant. The Evaporative technology is used in Hot and dry areas. In these areas it is more effective and cost efficient than the air conditioners. But in humid areas, Evaporative cooling does not bring thermal comfort. Thermal comfort is a state where our body feel good with respect to temperature of surrounding. Working principle Evaporative cooling: For Moist air: When hot and dry air pass through an evaporative pad (a wet pad, with same water quantity always during evaporative process), It take some water(wet vapor form) from pad and the heat require to evaporate water is taken from water itself. As latent heat is almost 100 times the sensible heat for water, So a small portion of water will evaporate, resulting in overall reduction of temperature of water and air leaving the air and water at wet bulb temperature of entering air. (refer to figure) ...

Vapor Compressor Refrigeration system

Vapor compressor refrigeration system is the most widely used refrigeration system worldwide in both commercial as well as in domestic. It has mainly four major components 1) Compressor 2)Condenser 3) Expansion valve 4) Evaporator. Working Principle: Each and every refrigerant have a certain temperature at certain pressure, where it can be converted in vapor or vice versa. Refrigerant in super heat state and low pressure suck by compressor and where it is compressed and as a result its temperature and pressure is increased by consuming high grade energy(electricity). The pressure of refrigerant after compressor is always higher than the saturated pressure of refrigerant at ambient temperature, so that it can converted into liquid in condenser. The energy consumed by the compressor to compress the refrigerant is divided in to two parts 1) The oil circulating in to compressor casing taking heat of compressor to maintain it below a specific temperature. 2) The remaining energy is...