modelSteamPipe
Detailed thermal advection model with thermal expansion effects using IF97 water vapour
Information
This models shows the mass, energy, and momentum balance equations for 1D flow of steam in a pipe, using the finite volume method. The pressure loss is assumed to be linear with the flow rate for simplicity. The inertial term and the kinetic term are neglected in the momentum balance equations, hence the pressure wave dynamics is not represented. The pipe is adiabatic, with zero energy storage in the walls. The industry-standard IF97 model is used to compute the steam properties.
The boundary conditions at the inlet are prescribed mass flow w_in_pipe and specific enthalpy h_in_pipe. The boundary condition at the outlet is constant pressure. At time = 0 the inlet flow is zero; at time = 1 the inlet flow is changed to 2 kg/s and at time = 10 the inlet specific enthalpy is raised by 5000 J/kg.
Parameters
| Type | Name | Default | Description |
|---|
| Integer | N | 10 | Number of nodes |
| SI.Volume | Vtot | 1 | Total volume |
| Real | w_nom | 2 | Nominal mass flow rate |
| Real | dp_nom | 1e5 | Nominal total pressure loss at full flow rate |
| Real | p_nom | 10e5 | Nominal pressure at outlet |
| Real | h_nom | 3.1e6 | Nominal specific enthalpy |
| SI.Pressure | p_start | p_nom | Initial value of pressure states |
| SI.SpecificEnthalpy | h_start | h_nom | Initial value of enthalpy states |
| Real | kf | w_nom/(dp_nom/N) | Friction coefficient |
| SI.Volume | V | Vtot/N | Total volume |
| SI.Density | rho_av | Medium.density_ph(p_nom + dp_nom/2, h_nom) | Average density |
| SI.Time | tau | Vtot*rho_av/w_nom | Estimated transport delay at nominal conditions |
Contents
| Name | Description |
|---|
 Medium | |