摘要：The article deals with the effect of the critical flow,which is examined at pumping of the differential pumping chamber of the Environmental Scanning Electron Microscope (ESEM). The article compares the state of the flow in the area of pumped chamber at pressure ratio on the apertures when the critical flow occurs and its advantages in design of the chambers versus the flow without the clogging the nozzle. Problematics were solved using finite volume method by Ansys Fluent system.
