The working principle of liquid ring vacuum pump is to suck gas based on the rotation of impeller and the liquid ring formed by liquid. The impeller of liquid ring pump is eccentric to the pump body, and the two ends are sealed by side covers. There are suction windows and exhaust windows on the end face of the side cover, which are connected to the inlet and outlet of the pump respectively. When the impeller rotates, the liquid is thrown to the inner wall of the pump body to form a liquid ring concentric with the impeller. A crescent-shaped working cavity is formed between the inner surface of the liquid ring and the surface of the impeller hub and the end face of the side cover. The blades on the impeller divide the cavity into several closed chambers with different volumes and no connection. In the first half of the impeller, the crescent-shaped cavity gradually increases and the gas is sucked in; in the second half of the impeller, the crescent-shaped cavity gradually decreases, the gas is compressed, and then discharged through the exhaust window.
During the operation of the liquid ring vacuum pump, the working liquid not only transfers energy, but also plays the role of sealing the working cavity and cooling the gas. Therefore, the sucked gas neither dissolves in the working liquid nor reacts chemically with the working liquid.
