Steady Flow Energy Equation Calculator

Heat added to the system (Q):

Work done by the system (W):

Mass flow rate (m):

Enthalpy at state 1 (h₁):

Enthalpy at state 2 (h₂):

Flow velocity at state 1 (v₁):

Flow velocity at state 2 (v₂):

Gravitational acceleration (g):

Height at state 1 (z₁):

Height at state 2 (z₂):

How This Is Calculated

$$ \dot{Q} + \dot{W} = \dot{m} \left(h_1 + \frac{v_1^2}{2} + gz_1\right) - \dot{m} \left(h_2 + \frac{v_2^2}{2} + gz_2\right) $$
where:

Q = Heat added to the system (W)

W = Work done by the system (W)

m = Mass flow rate (kg/s)

h₁ = Enthalpy at state 1 (J/kg)

h₂ = Enthalpy at state 2 (J/kg)

v₁ = Flow velocity at state 1 (m/s)

v₂ = Flow velocity at state 2 (m/s)

g = Gravitational acceleration (m/s²)

z₁ = Height at state 1 (m)

z₂ = Height at state 2 (m)

Assumptions

The system is in steady state.
Flow is uniform at inlets and outlets.
The flow is steady and isentropic.
Flow is single phase.

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