الفهرس 
THE TEST RIG AND THE EXPERIMENTAL WORKOnly 14 pages are availabe for public view
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Abstract
The present work is concerned with the investigation of the effect of some parameters on the performance of the water ring vacuum pump. Namely, these parameters are; eccentricity ratio (the ratio between eccentricity and casing inner diameter), the number of impeller blades and the impeller rotational speed.
A test rig was designed and constructed in a way suitable to measure the necessary independent parameters required for the study.
A special pump was designed and manufactured. The body of the pump is constructed from three different parts; two covers and a casing. Five different casing were manufactured to change the eccentricity ratio. Also, five impellers with different number of blades were manufactured. One of the above mentioned impellers (having 16 blades) is tested with the five different casings, while the casing resulting in the maximum eccentricity is tested using the other four impellers. All tests were carried out at three different rotational speeds.
The tests data were used to draw the pump characteristics. It was found that:
1) The performance characteristics of water ring vacuum pump show a mark dependence on the vacuum percentage developed by the pump.
2) The tests insured the remarkable effect of rotational speed variation on the pump performance. As the speed increases, suction capacity, vacuum percentage and brake power increase.
3) The eccentricity ratio has a great effect on water ring vacuum pump performance. Within the tested range, increasing this ratio, improves the pump performance that means to increase suction capacity and vacuum percentage.
4) Increasing number of impeller blades had also a noticeable effect on pump performance. As the number of impeller blades increases, suction capacity and vacuum percentage increase reaching a maximum value at a certain number of blades, after which these values begin to decrease with increasing the number of blades. The highest value of the maximum vacuum percentage occurs at higher number of blades as the rotational speed decreases, while the highest values of suction capacity occur approximately at the same number of blades (twenty) for all the rotational speeds.
5) It is noticed that at low vacuum percentage, the brake power consumed by the pump, having an eccentricity of 15mm, is higher than that of any other model. As the vacuum percentage gets higher than a certain value (around 0.3), the brake power becomes less than those of model 3 and model 4.