Research of guide vane proposals for the single-stage axial-flow fans used in the large generator

Based on the one-dimensional design method and under the condition of ideal gas, this paper analyses the proportion of swirl energy losses to the theoretical pressure rise of the axial-flow fans used in the China-made 300 MW Generator and WESTHOUSE 135 MW Generator, the former is 13.79% and the latter is 11.4%. The results both of the CFD numerical simulation and model-testing prove that the straightener vanes can change 90% of the swirl energy losses into the useful energy, they can improve the efficiency of the fan about 12.33% compared with the same fan without guide vanes.