# Calculating Steam Turbine output power

• Izazo
In summary, using the Mollier Chart and the turbine properties, the volume flow rate of the turbine affects the cost and size of the turbine.

#### Izazo

TL;DR Summary
What is the formula to calculate turbine output power, which uses the volume flow rate of turbine? (Turbine Physical dimensions are not given)
So I know the formula " W_turbine = m_flow rate * (H_in - H_out) " BUT is there any formula that utilizes the turbine volumetric flow rate (m^3/sec) at the outlet? The following data is available, I just need the formula...
P_in= 2.36 Mpa
P_out= 0.95 MPa
m_flow rate= 0.02 kg/sec
eff_turbine= 70 %
Turbine outlet volume flow rate= 2.4 m^3/sec

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You'll never get there that way. The properties of steam and water are nonlinear. You need reference to them.

Can you explain what you are trying to accomplish and why you prefer volume flow as the variable? That sounds like it may be the wrong approach.

anorlunda said:
You'll never get there that way. The properties of steam and water are nonlinear. You need reference to them.

Can you explain what you are trying to accomplish and why you prefer volume flow as the variable? That sounds like it may be the wrong approach.
So the main issue is that I have this research paper and that has done some thermodynamic analysis of organic Rankine cycle, and designed it for 2 KW output...I don't understand the meaning of "designed it for 2 KW output", because using the input and output data of turbine from the research paper and using formula "W_turbine = m_flow rate * (H_in - H_out) " the answer is very low.
So, I thought that volume flow rate defines the cost and size of the turbine, so they might have used another formula that utilizes volume flow rate of the turbine...
I

In general, the most efficient turbines use the highest possible pressures and temperatures. That minimized operating costs. But it might raise capital costs.

Most likely, they had 2 KW as a requirement. There may be constraints on the pressure and temperature of available fluids.

The place to start is the Mollier Chart for the organic fluid.

https://en.wikipedia.org/wiki/Enthalpy–entropy_chart
But if you want only an order of magnitude estimate, W_turbine = m_flow rate * (H_in - H_out) is a simple energy balance. That might be the best you can do without many days of work to learn about turbine design.