Water ring vacuum pump

In positive-displacement pumps, the gas drawn in gradually loses volume in the space between the impellers; as pressure increases, it is then discharged

An appropriate amount of water is placed in the pump body as the working fluid. When the impeller rotates in a clockwise direction, water is thrown outward by the impeller; due to centrifugal force, the water forms a closed ring of approximately uniform thickness, shaped according to the geometry of the pump chamber. The inner surface of the lower part of the water ring is in perfect tangency with the impeller hub, while the inner surface of the upper part of the water ring is in contact with the tips of the blades (in fact, the blades extend to a certain depth within the water ring). At this point, a crescent-shaped space is formed between the impeller hub and the water ring, and this space is further divided by the impeller into several small chambers, one for each blade. If 0° at the lower part of the impeller is taken as the starting point, then when the impeller has rotated 180°, the volume of the small chamber increases and it becomes connected to the suction port on the end face; at this point, gas is drawn in. Once suction is complete, the small chamber becomes separated from the suction port ； As the impeller continues to rotate, the small cavity becomes smaller, thereby compressing the gas ； When the small chamber is connected to the exhaust port, the gas is expelled outside the pump. In summary, a water ring pump relies on changes in the volume of its pumping chamber to achieve suction, compression, and exhaust, and therefore it belongs to the category of variable-volume vacuum pumps.

An appropriate amount of water is placed in the pump body as the working fluid. As the impeller rotates clockwise as shown in the diagram, water is thrown outward by the impeller; due to centrifugal force, the water forms a closed ring of approximately uniform thickness, shaped according to the geometry of the pump chamber. The inner surface of the lower part of the water ring is in perfect tangency with the impeller hub, while the inner surface of the upper part of the water ring is in contact with the tips of the blades (in fact, the blades extend to a certain depth within the water ring). At this point, a crescent-shaped space is formed between the impeller hub and the water ring, and this space is further divided by the impeller into several small chambers, one for each blade. If 0° at the lower part of the impeller is taken as the starting point, then when the impeller has rotated 180°, the volume of the small chamber increases and it becomes connected to the suction port on the end face; at this point, gas is drawn in. Once suction is complete, the small chamber becomes separated from the suction port ； As the impeller continues to rotate, the small cavity becomes smaller, thereby compressing the gas ； When the small chamber is connected to the exhaust port, the gas is expelled outside the pump.