Liquid kerosene flows through a venturi meter

Thermodynamics

Problem 1

A water pipe is connected to a double-U manometer as shown in the figure below. The dimensions of the system is displayed in the figure. The local atmospheric pressure is 14.7 psia. Determine the absolute pressure at the center of the water pipe. (The water density is ; The specific gravity (SG) of oil is 0.80; The SG of mercury is 13.6.)

Problem 2

Liquid kerosene flows through a Venturi meter, as shown in the figure below. The pressure of the kerosene in the pipe supports columns of kerosene that differ in height by 12 cm. Determine the difference in pressure between points a and b, in kPa. Does the pressure increase or decrease as the kerosene flows from point a to point b as the pipe diameter decreases? The atmospheric pressure is 101 kPa, the specific volume of kerosene is 0.00122 m3/kg, and the acceleration of gravity is g = 9.81 m/s2.

Problem 3

A gas is contained in a vertical, frictionless piston-cylinder device. The piston has a mass of 4 kg and a cross-sectional area of 35 cm2. A compressed spring above the piston exerts a force of 60 N on the piston. If the atmospheric pressure is 95 kPa, determine the pressure inside the cylinder.

Problem 4

As shown in the figure below, a vertical piston-cylinder assembly containing a gas is placed on a hot plate. The piston initially tests on the stops. With the onset of heating, the gas pressure increases. At what pressure, in bar, does the piston start rising? The piston moves smoothly in the cylinder and g = 9.81 m/s2.

Problem 5

As shown in the figure below, a gas contained in a vertical piston-cylinder assembly. A vertical shaft whose cross-sectional area is 0.8 cm2 is attached to the top of the piston. Determine the magnitude, F, of the force acting on the shaft, in N, required if the gas pressure is 3 bar. The masses of the piston and attached shaft are 24.5 kg and 0.5 kg, respectively. The piston diameter is 10 cm. The local atmospheric pressure is 1 bar. The piston moves smoothly in the cylinder and g = 9.81 m/s2.