摘要: Cold flow tests were conducted on a four nozzle gas educator system to evaluate the system's performance using a slotted mixing stack with slanted shroud and diffuser rings. The stack length-to-diameter ratios evaluated were 1.5 a... 展开 Cold flow tests were conducted on a four nozzle gas educator system to evaluate the system's performance using a slotted mixing stack with slanted shroud and diffuser rings. The stack length-to-diameter ratios evaluated were 1.5 and 2.25. The nozzles were constructed with a ratio of total area or primary flow to area of mixing stack of 2.5. One set of straight nozzles and another set, tilted at 15 degrees, were used. Secondary and tertiary pumping coefficients, and mixing stack pressure distributions were used to evaluate the slant shrouded mixing stacks. Pumping performance of the four straight nozzle shrouded system was found to be comparable to previously tested unshrouded models, showing no specific advantages. Pumping performance of the tilted nozzles and slanted shroud showed an improvement over the straight shroud model, with a noticeable increase in the tertiary pumping. 收起