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Solving problems, see how easy it is to perform pressure drop, diameter or mass flow rate calculations in a fully automated environment.

Calculation Options:

Two equation solvers are built to solve compressible, isothermal flow equations. Equation 1 is a simplified form without the log(P1/P2) term, which reduces the number of computational iterations. Equation 2 is considered more accurate than Equation 1.

Three options are available to find (1) Pressure drop, (2) Diameter, or (3) Mass flow rate.

Important to Note:

The software is designed with only the following Engineering units.

For Pipe Pressure Drop module: Pressure (bar), Pressure drop (bar), Temperature (oC), Density (kg/m3), Dynamic viscosity (cP), Kinematic viscosity (m2/s), Mass flow rate (kg/h), Volumetric flow rate (m3/h), Velocity (m/s), Pipe diameter (mm), Pipe roughness (mm), Pipe length (m).

For Steam Table module: Pressure (bar), Temperature (oC), Enthalpy (kJ/kg), Entropy (kJ/kg.K), Internal Energy (kJ/kg), Specific Volume (m3/kg), Heat capacity, Cp (kJ/kg.K), Density (kg/m3).

For Temperature-Enthalpy (T-h) diagram plotting: Temperature range 0 - 500 oC, Enthalpy range 0 - 4000 kJ/kg.

For Temperature-Entropy (T-S) diagram plotting: Temperature range 0 - 500 oC, Entropy range 0 - 10 kJ/kg.K

Application example 1 (Pressure drop): Determine Pressure loss in steam pipe

Steam pressure = 10 bar absolute

Steam flow rate = 8 kg/s = 28,800 kg/h

Dryness % = 100 (i.e. Saturated steam)

Pipe diameter = 254mm

Total pipe length = 500m (including valves and fittings equivalent length)

Pipe material: Steel

Answers:

Using Equation 1: Pressure drop = 0.6839 bar = 6.84 % = 0.1368 bar/100m.

Using Equation 2: Pressure drop = 0.6870 bar = 6.87 % = 0.1374 bar/100m.

Saturation temperature = 179.89 oC

Density = 5.15 kg/m3

Dynamic viscosity = 1.50E-02 cP

Kinematic viscosity = 2.92E-06 m2/s

Volumetric flow rate = 5592.2 m3/h

Flow velocity = 30.63 m/s

Download result print-out here.

Application example 2 (Isenthalpic process): Throttling by a control valve (eg., PRV) causing a local pressure drop.

Steam pressure at7 bar absolute and 95% dryness is reduced to 2 bar absolute by a control valve. Find the steam conditions after the control valve.

Assume the throttling process is an isenthalpic process. That is to say during the throttling process, no work is done by or on the system (dW=0), and no heat transfer (adiabatic) from or into the system (dQ=0).

Answers:

Using the T-h diagram for plotting and visual analysis, the steam conditions after the control valve is found as follows.

Download T-h plot and results print-out here.

Application example 3 (Isentropic process): Expansion in Turbine.

The inlet of a steam turbine are 90 bar absolute and 500 oC. The outlet steam pressure is 0.04 bar absolute. Find the steam outlet conditions.

Assume the expansion process in steam turbine is an isentropic process. That is to say it is a reversible adiabatic process; no friction (ideal expansion), and no transfer of heat (dQ=0).

Answers:

Using the T-S diagram for plotting and visual analysis, the steam outlet conditions is found as follows.

Download T-S plot and results print-out here.