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Mathematical modelling of an air conditioner using evaporative cooling (without compressor)(COP =10.99)

Air conditioners are used to provide thermal comforts in extremly hot conditions. But these are very high power consuming machines. An attempt is made to make an air conditioner using the both form of evaporative cooling. Evaporative cooling is the most powerful and cheapest cooling technology. When air blow over the water, it gets cool. Water evaporated with blowing air, utilize latent heat from water itself thus reducing overall temperature of air and water. For details in evaporative cooling, Please click on below link: http://athermocreation.blogspot.in/2017/10/evaporative-cooling.html As we know to increase the temperature of one liter of water by one degree, Sensible Heat required is 4.187 kJ. But to evaporate one kg of water, latent heat required is 2250 kJ which is almost 550 times the sensible heat. So to lower the temperature of water only a small portion of water evaporation required. Evaporative technology is of two types: 1. Direct Evaproative technology

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 condition from

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 machines(like data server rooms) so they function well and give best results. Thermal comfort: Thermal comfort is a state of mind when human body feel comfort

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 temperature. To liq