Take the readings when the measured torque shows its

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smaller increments on the torque as the fricition applied to the torque are increased. Take the readings when the measured torque shows its maximum. Repeat this step until approximately 10 different settings are obtained with the last setting with the turbine stopped. 7. After the shaft is fully stopped, completely loosen the torque brake and zero the friction gage. 8. Increase discharge by opening the pipe inlet valve to a runaway speed of 2000 rpm and repeat steps 2 through 7. 9. Open drain valves and allow the basin to drain until only a trickle of water flows over the weir. Wait for weir flow to stop, then measure the water depth indicated by the point gage ( H 0 in Figure 3).
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5 Measurements Record the measured quantities in Table 1. Data Acquisition Data Reduction H 0 [ft] H 1 [ft] [psi] T N [rpm] Q [m 3 g [kg/m 2 s 2 ] available [W] P [W] h Run 1 t [ ° C] = Run 2 t [ ° C] = Data Analysis 1. Determine the discharge through the system using the weir calibration equation Q = 2.49( H 1 - H 0 ) 2.48 (cfs) 2. Determine the efficiency of the turbine using the data reduction equation (3). 3. Plot the rotational speed N vs. the efficiency h of the turbine for each of the applied torque. Plot P available on the same graph. Show the results for the both runs. 4. Compare the curves determined experimentally with those provided in the literature. Further Considerations 1. At what speed does the efficiency peak (compare this value with data shown in Figure 2). Why does the efficiency vanish at zero rpm and again at runaway? 2. What could be done to the apparatus to increase the efficiency of the turbine? 3. Determine the value of the torque on the shaft by applying the angular momentum equation to the control volume specified in Figure 1. References Robertson, J.A. and Crowe, C.T. (1993). Engineering Fluid Mechanics, 5th edition, Houghton Mifflin, Boston, MA. White, F.M. (1994). Fluid Mechanics, 3rd edition, McGraw-Hill, Inc., New York, NY.
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Take the readings when the measured torque shows its...

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