Effects of Dump Gaps and Flow Distribution Ratios in Dump Diffuser

Abstract

In order to obtain the diffuser with deceleration and low loss pressure, FLUENT was used to study the diffuser model under the condition of different dump gap ratios and different outlet flow distribution ratios, and the static pressure recovery coefficient, total pressure loss coefficient and internal flow field characteristics under different conditions were obtained. It has been found that there is a suitable ratio of dump gap to achieve the best performance of the diffuser. Smaller or larger gaps will reduce the quality of the diffuser. In addition, the reasonable flow distribution ratio of the three channels of the diffuser will allow the overall performance of the diffuser to be better. Larger internal and external channel mass flow rate differences and a larger proportion of flame tunnel mass flow rate will increase the total pressure loss of the diffuser and reduce its performance.