2002 Volume 27 Issue 84 Pages 115-122
In uniform inlet duct systems, the flow distribution at inlets would become more uniform when the area ratio M_L (the total sectional areas of the branch ducts/the sectional area of the main duct) gets smaller. Based on this idea, precise flow analysis including combining pressure losses at each joint was done to consider relations between the area ratios M_L and flow distributions. Result of flow analysis clarified the following points: 1. The Influence of both the main duct combining loss on flow distributions and the branch duct combining loss on flow distributions are very large. 2. M_L is between 0.5 and 0.6 when the deviation of the flow distribution at the uniform inlet δV is smaller than 5% and the required total pressure coefficient K_P is smaller than 8. 3. K_P is decided by M_L uniquely. Based on those results, new design method using the area ratio M_L is proposed in this study. And to confirm the calculation results, the uniform inlet duct system is built, and experiments are done. It is clarified that the result of calculation almost agrees with the experimental result. It can be said that the proposed new design method based on M_L has been proved experimentally.
