Refrigerant Distributors And Multi-Outlet Valves
Distributors and multi-output TXVs are used for supply of the refrigerant multicircuit evaporators. When the evaporator has for over one refrigerant circuit the refrigerant fro m the expansion valve is supplied to each circuit through distributors. Design of all distributors ensures that die liquid-vapor mixture leaving the expansion valve equally and communicated to each evaporator circuits. If this design criteria were not met, the peak performance of the evaporator would be impossible, because some schemes, starved to death pairs, while others were filled with liquid. In some cases, a refrigerant distributor is an integral part of the expansion valve, while in others it is a separate unit.
Distributors function by increasing the speed of the refrigerant flowing from TXV in order to facilitate the complete mixing of liquid and flashed a pair of refrigerant. Increase the speed of the pressure is due to the static pressure of the refrigerant. As the velocity increases, the static pressure of the fluid decreases.
This will lead to more refrigerant flash, thereby reducing consumption through the distributor pipe. Therefore, the distributor design includes methods used to slow the refrigerant after she mixes to restore some die static pressure.
As the refrigerant passes through the small diameter distributor of pipes, the reduction in pressure occurs. This loss of pressure does not affect the capacity or efficiency of the system until the expansion valve is properly size and application. In any system, with or without a distributor, the refrigerant must undergo a pressure drop between the high and low pressure sides of the system. This differential pressure allows the refrigerant to evaporate at low temperatures.
On systems without distributors, all of differential pressure flow through the expansion valve hole. When the distributor works, part of a pressure drop occurs through valves flow with a hole and the other occurs in the distributor and the connection pipes. When properly sized valve with a hole will be larger TXVs inclusion distributor so that its contribution to the total pressure drop is reduced. Thus, the total pressure drop in the system and refrigerating effect evaporator are the same in any case.
Four different types of refrigerant distributors are often used in refrigeration systems. They are called centrifugal pumps, Venturi, differential pressure, and different types. Any of these distributors can be used with a standard, single-outlet or multi-output expansion valve. Each involves a different design, which distributes the fluid and flashed a pair of individual evaporator chains...
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