ABSTRACT
As can be expected, the amount of information obtained through a planned variation of system parameters is literally enormous. For conciseness, only a small sample of typical results, useful in establishing trends, is presented here. Effect of the coil pitch, i.e. the number of helical coil turns, on the dimensionless head coefficient is presented in FIGURE 4 as a function of the intake angle ratio <Pwi<Pa· It is apparent that doubling the number of turns, i.e. halving the pitch, roughly doubles the discharge head. On the other hand, the flow rate was found to be essentially independent of the pitch (FIGURE 5). Note, in general, the flow rate increases with a larger value of the water intake angle <Pw· This is clearly indicated in FIGURE 6. The water to air angle ratio represents the volume fraction of water to air in one complete coil. The flow rate peaks at 45 rpm in the present operating condition followed by a stall. Based on similar results it can be concluded that an increase in tube diameter results in higherQ.
