煤烧圆家重点实验宝 In core region f(2) 3-4 f2 b 4)mixing length l/b=0.11 /b=0.10 National Lab, of Coal Combustion. HUST Wuhan 430074 P R CHINA E-mail:pcbnlcc@hust.edu.cnNL CC National Lab. of Coal Combustion, HUST Wuhan 430074, P. R. CHINA E-mail: pcbnlcc@hust.edu.cn In core region, ( ) ' ' ( ) ' ' 2 1 b y f v v b y f v v ym y xm x = = (3-4) 4) mixing length l tx/b = 0.11 l ty/b = 0.10 (3-5)