Experiment title
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ASSignment
| 2.2. Experimental Theory In order to obtain laboratory results for the value of Cd, an experimental setup of venturimeter was used in the laboratory to calculate the value of Qa and Qt. The fig 1.3 shows the Venturimeter setup in the laboratory which indicates the inlet convergent limb and the throat is attached to the manometer to its left which will give the difference in height reading. And the flow to the manometer is regulated by means of a valve. An aided centrifugal pump is attached to the apparatus to regulate the flow of water by turning on the power supply. Fig 1.3: Venturimeter in laboratory. The following steps were performed to obtain the desired values in order to calculate the value of Cd. i. Switch on the motor and regulate the flow rate of the inlet valve starting from 32 L/min which is 0.54 Ls down to 12 L/min or 0.2 Ls. 10 ii. After a uniform flow is established with no eddied formation note the difference in the manometer reading of the right and the left limb as shown in fig 1.4 and fig 1.5. This difference value is denoted by hand is used to calculate the Theoretical Discharge Qt. Fig 1.4: Difference in Fig 1.5: Difference in Manometer readings Manometer readings. at 20 L/min. 24 L/min. iii. To obtain the value of actual discharge Qa, collect certain amount of water in the measuring tank which in this case is Land note the time in seconds. The fig 1.6 shows the volume scale of water collected in the tank. Fig 1.6: Volume of water in the tank. iv. Repeat the same experiment a few times to obtain different values of Qa and Qt. Calculate the value of Cd and tabulate all the values. |