Estimation Method of Displacement for Refrigeration Water Pumps
Water pumps are an essential component of the refrigeration system. The displacement of the water pumps affects the system performance; thus, a proper estimation and selection of suitable pumps is essential. This paper discusses the practical method for estimating the displacement of a refrigeration water pump.
The first step in the estimation of the pump displacement involves calculating the systems total flow rate, which is determined by the total heat load on the system. The total heat load includes the energy required by the evaporator, the energy required to heat the refrigerant, and the energy needed to compress the refrigerant. Once the total heat load is known, the flow rate for the system can be calculated using a refrigeration cycle diagram.
The next step is to determine the flow rate of the water pumps. Since the water is being supplied to the cooling coils directly from a reservoir, the flow rate of the pump should provide enough water flow to supply the cooling coils. This can be done by calculating the total heat load of the system, and then dividing this by the temperature difference between the reservoir and the cooling coils. Once this value is obtained, the flow rate of the pump can be determined.
Once the flow rate of the pump is known, the total displacement can be calculated by multiplying the flow rate by the pumps efficiency. The pumping efficiency is the ratio of the actual water flow rate delivered by the pump to the intended water flow rate. The total displacement is then calculated based on the flow rate and pump efficiency. The total displacement should be checked against the manufacturers suggested displacement, and if the displacement exceeds the manufacturers recommendation, a larger pump should be selected.
Finally, the last step in the estimation of the displacement of a refrigeration water pump involves selecting the most appropriate pumping unit for the application. Once the total displacement has been determined, the pump size should be selected based on the requirement of the system. The pump size should be chosen such that it is capable of providing the required flow rate, while also conforming to power requirements of the cooling coils. Selecting the right pump size is crucial, as the incorrect size will result in reduced system efficiency and inadequate cooling capacity.
In conclusion, accurate estimation of the displacement of a refrigeration water pump is important for proper water pump selection in the system. The aforementioned steps provide a practical approach for estimating the displacement of a pump for a refrigeration system. It is also important to remember to check the required displacement against the manufacturers suggested displacement, and to select an appropriately sized pump for the application.
