A closed cylindrical tank 5m high contains 2.5m of water. A 100mm diameter circular orifice is situated in the vertical side of the tank, 0.5m from the bottom. What air pressure must be maintained in the air above the surface of the water in order for the discharge in the orifice to be 98 L/s?

4. A horizontal boiler drum 6m long and 3m diameter is provided with an orifice 100mm in diameter at its bottom. It contains water up to a height of 2.4m. Calculate the time taken to empty the drum.

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A constant-area duct that is 20 cm in length by 2 cm in diameter is connected to a reservoir through a converging nozzle, as shown in Figure 9.13. For a reservoir pressure and tem- perature of 1 MPa and 500 K, determine the maximum air flow rate in kilograms per sec- ond through the system and the range of back pressures over which this flow is realized. Repeat these calculations for a converging nozzle with no duct. Assume that fis equal to 0.032 and that y - 1.4. f= 0.032 D-2 cm Isentropic flow P1,000 kPa I 500 K 20 cm