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Why coefficient of performance of absorption cycle is less than compression cycle?
In case of vapour compression cycle (VCC) the COP is given by (desired effect / work input). in the other words it can be defines as what we want and what we are paying for that... so in VCC the paying amount is very less as due to low temperature difference that why its value is more than 1. but in case of vapour absorption system the COP is given by (heat taken by evaporator/ heat given to generator). the heat input taken by evaporator is less as compared to heat given to generator.. that why its COP is less than 1......
What else can I help you with?
What is the difference between gas power cycles and vapour power cycles?
Vapor-compression cycle(See Heat pump and refrigeration cycle and Vapor-compression refrigeration for more details)The vapor-compression cycle is used in most household refrigerators as well as in many large commercial and industrial refrigeration systems. Figure 1 provides a schematic diagram of the components of a typical vapor-compression refrigeration system.Figure 1: Vapor compression refrigerationThe thermodynamics of the cycle can be analyzed on a diagram[11][12] as shown in Figure 2. In this cycle, a circulating refrigerant such as Freon enters the compressor as a vapor. From point 1 to point 2, the vapor is compressed at constant entropy and exits the compressor as a vapor at a higher temperature, but still below the vapor pressure at that temperature. From point 2 to point 3 and on to point 4, the vapor travels through the condenser which cools the vapor until it starts condensing, and then condenses the vapor into a liquid by removing additional heat at constant pressure and temperature. Between points 4 and 5, the liquid refrigerant goes through the expansion valve (also called a throttle valve) where its pressure abruptly decreases, causing flash evaporation and auto-refrigeration of, typically, less than half of the liquid.Figure 2: Temperature-Entropy diagramThat results in a mixture of liquid and vapor at a lower temperature and pressure as shown at point 5. The cold liquid-vapor mixture then travels through the evaporator coil or tubes and is completely vaporized by cooling the warm air (from the space being refrigerated) being blown by a fan across the evaporator coil or tubes. The resulting refrigerant vapor returns to the compressor inlet at point 1 to complete the thermodynamic cycle.The above discussion is based on the ideal vapor-compression refrigeration cycle, and does not take into account real-world effects like frictional pressure drop in the system, slight thermodynamic irreversibility during the compression of the refrigerant vapor, or non-ideal gas behavior (if any).More information about the design and performance of vapor-compression refrigeration systems is available in the classic Perry's Chemical Engineers' Handbook.[13]Vapor absorption cycleMain article: Absorption refrigerator In the early years of the twentieth century, the vapor absorption cycle using water-ammonia systems was popular and widely used. After the development of the vapor compression cycle, the vapor absorption cycle lost much of its importance because of its low coefficient of performance (about one fifth of that of the vapor compression cycle). Today, the vapor absorption cycle is used mainly where fuel for heating is available but electricity is not, such as in recreational vehicles that carry LP gas. It is also used in industrial environments where plentiful waste heat overcomes its inefficiency.The absorption cycle is similar to the compression cycle, except for the method of raising the pressure of the refrigerant vapor. In the absorption system, the compressor is replaced by an absorber which dissolves the refrigerant in a suitable liquid, a liquid pump which raises the pressure and a generator which, on heat addition, drives off the refrigerant vapor from the high-pressure liquid. Some work is needed by the liquid pump but, for a given quantity of refrigerant, it is much smaller than needed by the compressor in the vapor compression cycle. In an absorption refrigerator, a suitable combination of refrigerant and absorbent is used. The most common combinations are ammonia (refrigerant) and water (absorbent), and water (refrigerant) and lithium bromide[absorbent].
Bell Coleman Cycle it is the air refregeration cycle?
The Bell-Coleman Cycle is also known as the Air-Standard Refrigeration Cycle or Reverse Brayton Cycle. This 4-process refrigeration cycle involves isentropic compression, followed by isobarric heat rejection, then isentropic expansion (usually by a turboexpander), and finally isobarric heat intake.This cycle is commonly used in jet aircraft, using engine bleed air for compression and venting to the atmosphere. It is also commonly used in commercial air liquification plants.
How does the thermal efficiency of an ideal Otto Cycle change with the compression ratio of the engine and the specific heat ratio of the working fluid?
The answer is 38.
What is carnot engine in thermodynamics?
A Carnot cycle representes a gas undergoing a theoretical - means it cannot be implemented realistically - thermodynamic cycle composed of 4 reversible steps (meaning you can go back and everything will be back to the state it was, or scientifically speaking, the entropy of the universe will remain constant): 1- isothermal expansion of the gas (working fluid) - heat is added from the surroundings to the working fuild and it expands at constant temperature; 2- isentropic expansion of the gas - the gas is allowed to expand and produce work; 3- isothermal compression of the gas - the gas rejects heat to the surroundings at constant temperature; 4- isentropic compression of the gas - the gas is compressed and work is need for that compression.
What is 4stroke engine?
A 4 stroke engine takes 4 strokes to complete a cycle. 1, intake. 2, compression. 3, ignition/power. 4, exhaust.
What is the significance of the coefficient of performance in the refrigeration cycle?
The coefficient of performance in the refrigeration cycle is important because it indicates how efficiently the refrigeration system can transfer heat. A higher coefficient of performance means the system is more efficient at cooling, which can lead to lower energy consumption and cost savings.
What has the author A M S Qasrawi written?
A. M. S. Qasrawi has written: 'The design and development of an absorption cycle heat pumpoptimised for the achievement of maximum coefficient ofperformance'
How water flow rate affect performance of vapour compression cycle?
An increase in water flow rate can improve the performance of a vapor compression cycle by enhancing heat transfer in the condenser and evaporator. This results in better cooling capacity and efficiency of the cycle. However, excessive water flow rates can lead to increased pumping power requirements and higher operating costs.
What is the difference between gas power cycles and vapour power cycles?
Vapor-compression cycle(See Heat pump and refrigeration cycle and Vapor-compression refrigeration for more details)The vapor-compression cycle is used in most household refrigerators as well as in many large commercial and industrial refrigeration systems. Figure 1 provides a schematic diagram of the components of a typical vapor-compression refrigeration system.Figure 1: Vapor compression refrigerationThe thermodynamics of the cycle can be analyzed on a diagram[11][12] as shown in Figure 2. In this cycle, a circulating refrigerant such as Freon enters the compressor as a vapor. From point 1 to point 2, the vapor is compressed at constant entropy and exits the compressor as a vapor at a higher temperature, but still below the vapor pressure at that temperature. From point 2 to point 3 and on to point 4, the vapor travels through the condenser which cools the vapor until it starts condensing, and then condenses the vapor into a liquid by removing additional heat at constant pressure and temperature. Between points 4 and 5, the liquid refrigerant goes through the expansion valve (also called a throttle valve) where its pressure abruptly decreases, causing flash evaporation and auto-refrigeration of, typically, less than half of the liquid.Figure 2: Temperature-Entropy diagramThat results in a mixture of liquid and vapor at a lower temperature and pressure as shown at point 5. The cold liquid-vapor mixture then travels through the evaporator coil or tubes and is completely vaporized by cooling the warm air (from the space being refrigerated) being blown by a fan across the evaporator coil or tubes. The resulting refrigerant vapor returns to the compressor inlet at point 1 to complete the thermodynamic cycle.The above discussion is based on the ideal vapor-compression refrigeration cycle, and does not take into account real-world effects like frictional pressure drop in the system, slight thermodynamic irreversibility during the compression of the refrigerant vapor, or non-ideal gas behavior (if any).More information about the design and performance of vapor-compression refrigeration systems is available in the classic Perry's Chemical Engineers' Handbook.[13]Vapor absorption cycleMain article: Absorption refrigerator In the early years of the twentieth century, the vapor absorption cycle using water-ammonia systems was popular and widely used. After the development of the vapor compression cycle, the vapor absorption cycle lost much of its importance because of its low coefficient of performance (about one fifth of that of the vapor compression cycle). Today, the vapor absorption cycle is used mainly where fuel for heating is available but electricity is not, such as in recreational vehicles that carry LP gas. It is also used in industrial environments where plentiful waste heat overcomes its inefficiency.The absorption cycle is similar to the compression cycle, except for the method of raising the pressure of the refrigerant vapor. In the absorption system, the compressor is replaced by an absorber which dissolves the refrigerant in a suitable liquid, a liquid pump which raises the pressure and a generator which, on heat addition, drives off the refrigerant vapor from the high-pressure liquid. Some work is needed by the liquid pump but, for a given quantity of refrigerant, it is much smaller than needed by the compressor in the vapor compression cycle. In an absorption refrigerator, a suitable combination of refrigerant and absorbent is used. The most common combinations are ammonia (refrigerant) and water (absorbent), and water (refrigerant) and lithium bromide[absorbent].
What is the compression cycle?
the vapor compression cycle is the cycle used in the process of the refrigerator. for more info go to www.wikipedia.com . thanx for asking ur questions!!!!! ~tammie
What is the vapor compression cycle?
the vapor compression cycle is the cycle used in the process of the refrigerator. for more info go to www.wikipedia.com . thanx for asking ur questions!!!!! ~tammie
Derivation of coefficient of performance of carnot refrigeration cycle?
COF = h1-h4/h2-h1=T1(s1-s4)/T2-T1(s1-s4)=T1/T2-T1
How do you improve the performance of vapor compressor refrigeration cycle?
In practical applications, vapor-compression refrigeration systems are the most commonly used refrigeration systems, and each system employs a compressor. In a basic vapor compression refrigeration cycle as shown in Figure 3.28, four major thermal processes take place as follows: • evaporation, • compression, • condensation, and • expansion.
What effect does the ozones absorption of ultravioletradiation have on the stratosphere?
The ozone absorption of UV rays maintain a ozone cycle. This ozone cycle is maintained by sun's rays.
What is a two-cycle engine how does it work?
compression power
What are the differences between a 4-cycle and a 2-cycle engine in terms of performance and efficiency?
A 4-cycle engine has four stages (intake, compression, power, exhaust) in one cycle, while a 2-cycle engine has only two stages (combustion and exhaust). 4-cycle engines typically have better fuel efficiency and lower emissions, but 2-cycle engines are simpler and can produce more power for their size.
If compression ratio is samethen whose efficiency will be greater diesel cycle or otto cycle?
Diese
