Experimental Study of Effect of Length to Diameter Ratio of Drive Pipe on The Ram Pump Performance

Document Type : Research Paper



In this study, experimental model was used in order to evaluate the effect of diameter and length of drive pipe on ram pumps characteristic curves. To do so, after developing a ram pump device with inner diameter of 51mm and the construction of ancillary equipment, tests were carried out in six scenarios by changing the ratio of length to diameter of drive pipe in amounts of equal to 100, 200, 300, 400, 500 and 600. In each scenario with a change in supply head of pumping system and delivered of its, the ram pump performance was evaluated and quantities of pumping discharge (q), wasting discharge (Q) and frequency of impulse valve (n) were recorded. By analyzing the results and evaluating the dependent parameters versus effective independent parameters on the ram pump performance, the ram pump characteristic curves including relative pumping discharge (q/QT), relative wasting discharge (Q/QT) and impulse valve parameter (nD/v0) versus pressure head ratio (h/hm) per each of length to diameter ratios of drive pipe (L/D) were presented, and general equation of pump efficiency were determined. The result showed that along with increasing the length of drive pipe to 400 times of its diameter, the ram pump made is able to pump water to a height equal to twice supply head with efficiency of 48 percent.