Question

A steam turbine operates with 1.6 MPa and 350°C steam at its inlet and saturated vapor at 30°C at its exit. The mass flow rate of the steam is 22.4 kg/s, and the turbine produces 12,350 kW of power. Determine the rate at which heat is lost through the casing of this turbine. The enthalpies are h1 = 3146 kJ/kg and h2 = 2555.6 kJ/kg

Answer 1

Answer:

$\dot{Q_{out}} = 874.96 KW$

Explanation:

given,

steam turbine operates at P₁ = 1.6 MPa

steam inlet temperature T₁= 350°C

saturation vapor T₂= 30°C

the enthalpies (h₁) = 3146 kJ/kg

h₂ = 2555.6 kJ/kg

assuming no change in internal energy

$\dot{E_{in}} = \dot{E_{out}}$

$\dot{m_1}h_1 = \dot{m_2}h_2 + \dot{w_{out}}+\dot{Q_{out}}$

$\dot{Q_{out}} = \dot{m}(h_1-h_2)-\dot{W_{out}}$

$\dot{Q_{out}} = 22.4\times (3146-2555.6)-12,350$

$\dot{Q_{out}} = 874.96 KW$