No abstract

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.

The article deals with the impact of the shape of the differential pumped chamber of the Environmental electron microscope on resultant value of average Normalized density number on the path of the primary electron beam which has directly proportional influence on the dispersion of this beam and thereby influence on sharpness resulting image. Analysis were made using finite volume method in Ansys Fluent system with the respect to critical flow created behind the aperture which separates differential pumped chamber from the specimen chamber.

The thesis follows to the work of G.D. Danilatos occupy Differential Pumping System with fast stopper focusing on dew design for environmental scanning electron microscope. Thesis concern divider located in the chamber differential pumping and its influence on the nature of the flow. Simulation of individual variants was evaluated using the program Ansys Fluent, which calculates with the method final volumes as opposed to calculations performed by G. D. Danilatos which uses the statistical method Monte Carlo.

This article builds on a series of articles devoted to the issue of pumping in the differentially pumped chamber. This article is based on a study by Dr. Danilatos, where pumping of the differential pumped chamber is solved using the Monte Carlo statistical method. For solving the issue use the mechanics continuum with experimental verification. The work deals with the influence of location measuring Pitot tube in experimental chamber.