Dynamic characteristics of threshold values and extension field selections for a vacuum-blowing cleaning system

Abstract

To provide theoretical guidelines for threshold value selection on the performance characteristics of an extension field, the flow characteristics in a vacuum-blowing cleaning system was simulated using the average velocity and pressure at the front inlet surface and the average velocity of the outlet surface as indices to evaluate the effects of the extension field’s structural parameters. We found that the extension field parameters have implications for the simulation calculations, and that each parameter has a corresponding threshold. If the structural parameter is greater than the corresponding threshold, the calculation result is not affected and the threshold values are analyzed using computational fluid dynamics. The dimensions of the front, back, left, and right extension fields were as follows: lf = lb = ll = lr = 210 mm, and θf = θb = θl = θr = 55°. The flow field distribution characteristics are not distinctly different, with or without the extension field corner. The extension field with a corner can be used if high accuracy is required; however, to reduce the need for grid computation and shorten the calculation time, the corner extension field model is not recommended. Finally, the simulation results were verified experimentally, and can be used to improve the accuracy of the calculations and reduce the required computational resources.