CAJ | 학술논문

采用格子Boltzmann方法对雷诺数(基于射流出口宽度和出口最大速度)为42和65的二维不可压缩平面射流进行了数值模拟.研究结果表明,在射流的自相似区,射流中心轴线速度按-1/3指数规律衰减并且射流按2/3指数率扩展,与理论分析及实验结果吻合.在射流的远场区域,中心轴线上瞬态速度的时间历程与频谱分析展示出速度的周期变化特性,并且周期性分量引起的相互作用不应被忽略；相比较而言,速度的周期性分量在近场区不明显.
채용격자Boltzmann방법대뢰낙수(기우사류출구관도화출구최대속도)위42화65적이유불가압축평면사류진행료수치모의.연구결과표명,재사류적자상사구,사류중심축선속도안-1/3지수규률쇠감병차사류안2/3지수솔확전,여이론분석급실험결과문합.재사류적원장구역,중심축선상순태속도적시간역정여빈보분석전시출속도적주기변화특성,병차주기성분량인기적상호작용불응피홀략；상비교이언,속도적주기성분량재근장구불명현.
A two-dimensional (2-D) incompressible plane jet is investigated using the lattice Boltzmann method (LBM) for low Reynolds numbers of 42 and 65 based on the jet-exit-width and the maximum jet-exit-velocity.The results show that the mean centerline velocity decays as x-1/3 and the jet spreads as x2/3 in the self-similar region,which are consistent with the theoretical predictions and the experimental data.The time histories and PSD analyses of the instantaneous centerline velocities indicate the periodic behavior and the interaction between periodic components of velocities should not be neglected in the far field region,although it is invisible in the near field region.