| 摘要 |
A centrifugal pump having an impeller rotatable about an axis of rotation at its center has its operation controlled so as to regulate the size of a gas bubble. When pumping a liquid or suspension (such as paper pulp with a consistency of about 8-15 percent) which contains gas, the gas has a tendency to collect adjacent the impeller center, and impede operation of the pump. Using a number of electrodes which extend into operative association with the chamber of the pump in which the gas bubble tends to collect, and by taking advantage of the differences in electrical conductivity of the gas as compared to the liquid or suspension being pumped, the size of the gas bubble may be determined. When the size is too large, gas is automatically discharged from the pump. When an asynchronous motor drives the impeller, the pump power consumption can also be determined, and additionally the gas bubble size may be used to regulate the pump pressure head and the speed of the pump in order to obtain optimum operating efficiency. |
