Air enters a 28-cm diameter pipe steadily at 200 kPa and 20°C with a velocity of 5 m/s. Air is heated as it flows and leaves the pipe at 180 kPa and 40 °C. Determine the mass flow rate of air and the velocity at the exit.

The mass flow rate of air is 0.732 kg/s.

The velocity at the exit is 5.927 m/s.

Explanation:

Given that,

Diameter = 28 cm

Enter pressure= 200 kPa

Enter temperature = 20°C

Velocity = 5 m/s

Exit pressure = 180 kPa

Exit temperature = 40°C

We need to calculate the mass flow rate of air

Using formula of mass flow rate

Put the value into the formula

We need to calculate the volume flow rate

Using formula of volume flow rate

We need to calculate the velocity at the exit

Using formula of velocity

Put the value into the formula

Hence, The mass flow rate of air is 0.732 kg/s.

The velocity at the exit is 5.927 m/s.

grav potential energy

that would be because of both gravity and friction. so     c