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对四角切圆燃烧锅炉进行数值模拟时，由于四个角上的射流和计算网格面的夹角接近４５°，往往产生严重的伪扩散问题，极大地影响计算精度。为此，本文设计了一受限射流实验，模拟炉内一角上的时流，拟寻求减小伪扩散的有效方法。针对受限射流，分别采用三种计算格式：混合、ｑｕｉｃｋ和２７点差分格式，编制程序，进行模拟计算，以比较三种格式减小伪扩散的效果。其中“２７点差分格式”是作者所提出的一种较为新颖的计算格式，故对其作了较详细的介绍。最后，将计算结果和实验数据进行了初步比较，结果表明２７点差分格式对减小伪扩散，有着良好的效果。
When numerical simulation of Tangentially Fired Boiler, the angle between the jet and the calculated grid surface at four corners is close to 45 °, which often leads to serious pseudo-diffusion problem and greatly affects the calculation precision. Therefore, a restricted jet experiment was designed in this paper to simulate the current flow in the corner of the furnace. It is proposed to find an effective method to reduce the pseudo-diffusion. For the confined jets, three kinds of calculation formats are used respectively: hybrid, quick and 27-point difference format, and the program is programmed to simulate and compare the three formats to reduce the effect of pseudo-diffusion. The “27-point difference format” is a relatively new calculation format proposed by the author, so it is introduced in more detail. Finally, a preliminary comparison between the calculated and experimental data shows that the 27-point difference scheme has a good effect on reducing pseudo-diffusion.