WOLFRAM SYSTEM MODELER

pressureLoss

Return pressure loss dp as function of mass flow rate m_flow for a thick edged orifice

Wolfram Language

In[1]:=
SystemModel["Modelica.Fluid.Fittings.BaseClasses.Orifices.ThickEdgedOrifice.pressureLoss"]
Out[1]:=

Information

This information is part of the Modelica Standard Library maintained by the Modelica Association.

This function returns the pressure loss dp as function of mass flow rate m_flow for a thick edged orifice. The details of the function are described here.

The orifice characteristic is valid for constant density and constant dynamic viscosity. It can be approximately also used for compressible media. This is performed by providing the upstream density and upstream dynamic viscosity. In order to be able to regularize density and dynamic viscosity around zero mass flow rate, the two quantities have to be given if fluid flows from port_a to port_b (d_a, eta_a) and if fluid flows from port_b to port_a (d_b, eta_b).

Syntax

dp = pressureLoss(m_flow, geometry, d_a, d_b, eta_a, eta_b, dp_small, m_flow_small)

Inputs (8)

m_flow

Type: MassFlowRate (kg/s)

Description: Mass flow rate (= port_a.m_flow)

geometry

Type: Geometry

Description: Geometry of bend

d_a

Type: Density (kg/m³)

Description: Density at port_a when fluid is flowing from port_a to port_b

d_b

Type: Density (kg/m³)

Description: Density at port_b when fluid is flowing from port_b to port_a

eta_a

Type: DynamicViscosity (Pa⋅s)

Description: Dynamic viscosity at port_a when fluid is flowing from port_a to port_b

eta_b

Type: DynamicViscosity (Pa⋅s)

Description: Dynamic viscosity at port_b when fluid is flowing from port_b to port_a

dp_small

Type: AbsolutePressure (Pa)

Description: Small pressure drop used for regularization if m_flow=f(...,dp_small,..,dp)

m_flow_small

Type: MassFlowRate (kg/s)

Description: Small mass flow rate used for regularization if dp=f_inv(...,m_flow_small,m_flow)

Outputs (1)

dp

Type: Pressure (Pa)

Description: Pressure loss