煤烧圆家重点实验宝 2. Turbulence average 1)time average 0 T→> 2-1) 2)space average ()=lim-(x,10)d 2-2) X→0 X 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 2. Turbulence average 1) time average  → = = T T t x t dt T x 0 0 0 ( , ) 1  ( ) lim  (2-1) 2) space average  → = x x s x t dx x t 0 0 0 ( , ) 1  ( ) lim  (2-2)