Question

Steam enters and leaves a horizontal 1D pipe steadily at a constant speed with the specific enthalpy to be 4000 kJ/kg and 1500 kJ/kg respectively. Assuming a mass flow rate of 0.5 kg/sec and If there is no significant change in potential energy from inlet to exist, determine the rate of heat transfer between the pipe and its surroundings.

Answer 1

The rate of heat transfer between pipe and its surrounding is found to be 1250 KW

Step-by-step explanation:

Assuming no significant change in potential energy. When we apply the first law of thermodynamics to the given system of 1-D pipe, we get the following expression:

Q = m(h₁ - h₂)

where,

Q = Heat Transfer between pipe and surrounding = ?

m = mass flow rate of steam = 0.5 kg/sec

h₁ = Specific Enthalpy of steam at entrance = 4000 KJ/kg

h₂ = Specific Enthalpy of steam at exit = 1500 KJ/kg

Therefore, using these values in the equation, we get the value of heat transfer:

Q = (0.5 kg/sec)(4000 KJ/kg - 1500 KJ/kg)

Q = 1250 KW