Pressure loss functions for edged bends
This package contains utility functions and records for the EdgedBend fitting component.
Extends from Modelica.Icons.Package (Icon for standard packages).
Name | Description |
---|---|
massFlowRate | Return mass flow rate m_flow as function of pressure loss dp for a curved bend |
pressureLoss | Return pressure loss dp as function of mass flow rate m_flow for a curved bend |
Geometry | Geometric data for a curved bend |
Return mass flow rate m_flow as function of pressure loss dp for a curved bend
This function returns the mass flow rate m_flow as function of pressure loss dp for an edged bend. The details of the function are described here.
The bend 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).
Extends from Modelica.Icons.Function (Icon for functions).
Name | Description |
---|---|
dp | Pressure loss [Pa] |
geometry | Geometry of bend |
d_a | Density at port_a when fluid is flowing from port_a to port_b [kg/m3] |
d_b | Density at port_b when fluid is flowing from port_b to port_a [kg/m3] |
eta_a | Dynamic viscosity at port_a when fluid is flowing from port_a to port_b [Pa.s] |
eta_b | Dynamic viscosity at port_b when fluid is flowing from port_b to port_a [Pa.s] |
dp_small | Small pressure drop used for regularization if m_flow=f(...,dp_small,..,dp) [Pa] |
m_flow_small | Small mass flow rate used for regularization if dp=f_inv(...,m_flow_small,m_flow) [kg/s] |
Name | Description |
---|---|
m_flow | Mass flow rate (= port_a.m_flow) [kg/s] |
Return pressure loss dp as function of mass flow rate m_flow for a curved bend
This function returns the pressure loss dp as function of mass flow rate m_flow for an edged bend. The details of the function are described here.
The bend 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).
Extends from Modelica.Icons.Function (Icon for functions).
Name | Description |
---|---|
m_flow | Mass flow rate (= port_a.m_flow) [kg/s] |
geometry | Geometry of bend |
d_a | Density at port_a when fluid is flowing from port_a to port_b [kg/m3] |
d_b | Density at port_b when fluid is flowing from port_b to port_a [kg/m3] |
eta_a | Dynamic viscosity at port_a when fluid is flowing from port_a to port_b [Pa.s] |
eta_b | Dynamic viscosity at port_b when fluid is flowing from port_b to port_a [Pa.s] |
dp_small | Small pressure drop used for regularization if m_flow=f(...,dp_small,..,dp) [Pa] |
m_flow_small | Small mass flow rate used for regularization if dp=f_inv(...,m_flow_small,m_flow) [kg/s] |
Name | Description |
---|---|
dp | Pressure loss [Pa] |
Geometric data for a curved bend
This record is used to define the geometric (constant) data of an edged bend. The details of the record are described here.
Extends from Modelica.Icons.Record (Icon for records).
Name | Description |
---|---|
d_hyd | Hydraulic diameter [m] |
delta | Angle of turning [rad] |
K | Absolute roughness, with a default for a smooth steel pipe [m] |