1. A positive-displacement flow meter is used to measure the flow of liquid Freon- 12 at 20?C. A flow rate of 2.35 gal/min is indicated. What is the mass flow in kg/s?
2. A sonic nozzle is to be used to measure the mass flow of nitrogen at low-velocity upstream conditions of 50?C and 800 kPa. The discharge coefficient is 0.97 ± 0.5 percent. The upstream pressure is measured with a transducer having an upper range of 1 MPa and an uncertainty of ±1 percent of full scale. The upstream temperature is measured with a thermocouple having an uncertainty of ±1?C. The nozzle has a throat diameter of 2 cm and discharges into a large chamber maintained at a pressure of 100 kPa. Calculate the flow rate of nitrogen in kg/s for these conditions and its uncertainty.