In today's society, cooling equipment plays a big role, especially industrial refrigeration and large chillers. The evaporator of large-scale refrigeration equipment generally uses a flooded evaporator. It has high heat transfer energy, easy to realize the stable operation of the device, and convenient for cooling capacity distribution. Especially for chillers, this type of evaporator is often used.
How to adjust the liquid supply of a flooded evaporator is an important part of refrigeration equipment such as chillers. The adjustment of the liquid supply cannot use superheat as a detection parameter (because no matter how the load changes, the outlet is always saturated with gas). By adjusting the liquid supply volume, the control liquid level is maintained within the specified range, so that the refrigeration temperature reaches the set requirement. If the amount of liquid supplied by the chiller is less than the amount of gas drawn from the evaporator, the liquid level of the refrigerant drops; otherwise, the liquid level drops.
For refrigeration equipment such as industrial chillers that use a flooded evaporator, the refrigeration system is equipped with equipment with a free liquid surface, which requires a specified liquid level inside the container to ensure the normal operation of the refrigeration device of the chiller. For example, to maintain the refrigeration liquid level in the intercooler, low-pressure circulating liquid tank and other containers, in the oil system, it is necessary to control the oil level in the oil separator, oil collector and crankcase, and control the oil discharge and refueling according to the oil level. All belong to the category of liquid level control.