| Fully developed incompressible sticky turbulent flow in inlet pipe and conical dif-fuser having a total divergence of 80 and an area ratio of 4:1 has been simulated veryaccurately by a DLR turbulent model and it's BFC (Boundary -Fitted Coordinates)method. The pipe entry Reynolds number is 2.93×105 and 1.16×105 respectively. Basedon the near wall denseness model radial fitted-body nonuniform grid system and otherconditions, increasing the number of grids in the whole flow area, thickening grids in thevicinity of the wall, especially in the viscous sublayer, analysing the effective degree ofcalculated results according to numerical simulation of eighteen cases under the differentcalculated conditions, such as different model constantsσ1 and C2, grid disposition andnumerical entering boundary conditions. The parameter distributions of the whole lowarea and wall have been given respectively, including the distributions of the mean flowvelocity (?) along main flow, mean pressure (?), turbulence energy k, turbulence dissipationε,eddy kinematic viscosity vt and the coefficient of wall pressure Cpw. The more accuratelynumerical prediction results, which haven't been gotten using material and model exper-iment have been gotten. These results offer the basis for turbulence theoretical researchand engineering technical application.At last, the research has been summarized and the prospects have been put forwardin this article.
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