Modelica.Fluid.Dissipation.PressureLoss.StraightPipe

Information

Straight Pipe

Laminar flow

Calculation of pressure loss in a straight pipe for laminar flow regime of single-phase fluid flow only. See more information.

Turbulent flow

Calculation of pressure loss in a straight pipe for turbulent flow regime of single-phase fluid flow only considering surface roughness. See more information.

Overall flow

Calculation of pressure loss in a straight pipe for laminar or turbulent flow regime of single-phase fluid flow only considering surface roughness. See more information.

Two phase overall flow

Calculation of pressure loss for two phase flow in a horizontal or vertical straight pipe for an overall flow regime considering frictional, momentum and geodetic pressure loss. See more information.

Package Content

Name	Description
dp_laminar_DP	Pressure loss of straight pipe | calculate pressure loss| laminar flow regime (Hagen-Poiseuille)
dp_laminar_MFLOW	Pressure loss of straight pipe | calculate mass flow rate | laminar flow regime (Hagen-Poiseuille)
dp_laminar_IN_con	Input record for function dp_laminar_DP and dp_laminar_MFLOW
dp_laminar_IN_var	Input record for function dp_laminar_DP and dp_laminar_MFLOW
dp_overall_DP	Pressure loss of straight pipe | calculate pressure loss | overall flow regime | surface roughness
dp_overall_MFLOW	Pressure loss of straight pipe | calculate mass flow rate | overall flow regime | surface roughness
dp_overall_IN_con	Input record for function dp_overall_DP and dp_overall_MFLOW
dp_overall_IN_var	Input record for function dp_overall_DP and dp_overall_MFLOW
dp_turbulent_DP	Pressure loss of straight pipe | calculate pressure loss | turbulent flow regime | surface roughness
dp_turbulent_MFLOW	Pressure loss of straight pipe | calculate mass flow rate | turbulent flow regime | surface roughness
dp_turbulent_IN_con	Input record for function dp_turbulent_DP and dp_turbulent_MFLOW
dp_turbulent_IN_var	Input record for function dp_turbulent_DP and dp_turbulent_MFLOW
dp_twoPhaseOverall_DP	Pressure loss of straight pipe for two phase flow | calculate (frictional, momentum, geodetic) pressure loss
dp_twoPhaseOverall_IN_con	Input record for function dp_twoPhaseOverall_DP
dp_twoPhaseOverall_IN_var	Input record for function dp_twoPhaseOverall_DP

Modelica.Fluid.Dissipation.PressureLoss.StraightPipe.dp_laminar_DP

Information

Calculation of pressure loss in a straight pipe for laminar flow regime of an incompressible and single-phase fluid flow only.

Generally this function is numerically best used for the incompressible case , where the mass flow rate (m_flow) is known (as state variable) in the used model and the corresponding pressure loss (DP) has to be calculated. On the other hand the function dp_laminar_MFLOW is numerically best used for the compressible case if the pressure loss (dp) is known (out of pressures as state variable) and the mass flow rate (M_FLOW) has to be calculated. See more information.

Inputs

Name	Description
Constant inputs
IN_con	Input record for function dp_laminar_DP
Variable inputs
IN_var	Input record for function dp_laminar_DP
Input
m_flow	Mass flow rate [kg/s]

Outputs

Name	Description
DP	Output for function dp_laminar_DP [Pa]

Modelica.Fluid.Dissipation.PressureLoss.StraightPipe.dp_laminar_MFLOW

Information

Calculation of pressure loss in a straight pipe for laminar flow regime of an incompressible and single-phase fluid flow only.

Generally this function is numerically best used for the compressible case , where the pressure loss (dp) is known (out of pressures as state variable) in the used model and the corresponding mass flow rate (M_FLOW) has to be calculated. On the other hand the function dp_laminar_DP is numerically best used for the incompressible case if the mass flow rate (m_flow) is known (as state variable) and the pressure loss (DP) has to be calculated. See more information.

Inputs

Name	Description
Constant inputs
IN_con	Input record for function dp_laminar_MFLOW
Variable inputs
IN_var	Input record for function dp_laminar_MFLOW
Input
dp	Pressure loss [Pa]

Outputs

Name	Description
M_FLOW	Output for function dp_laminar_MFLOW [kg/s]

Modelica.Fluid.Dissipation.PressureLoss.StraightPipe.dp_laminar_IN_con

Information

Parameters

Name	Description
Straight pipe
d_hyd	Hydraulic diameter [m]
L	Length [m]

Modelica.Fluid.Dissipation.PressureLoss.StraightPipe.dp_laminar_IN_var

Information

Parameters

Name	Description
Fluid properties
eta	Dynamic viscosity of fluid [Pa.s]
rho	Density of fluid [kg/m3]

Modelica.Fluid.Dissipation.PressureLoss.StraightPipe.dp_overall_DP

Information

Calculation of pressure loss in a straight pipe for overall flow regime of an incompressible and single-phase fluid flow only considering surface roughness.

Generally this function is numerically best used for the incompressible case , where the mass flow rate (m_flow) is known (as state variable) in the used model and the corresponding pressure loss (DP) has to be calculated. On the other hand the function dp_overall_MFLOW is numerically best used for the compressible case if the pressure loss (dp) is known (out of pressures as state variable) and the mass flow rate (M_FLOW) has to be calculated. See more information.

Inputs

Name	Description
Constant inputs
IN_con	Input record for function dp_overall_DP
Variable inputs
IN_var	Input record for function dp_overall_DP
Input
m_flow	Mass flow rate [kg/s]

Outputs

Name	Description
DP	Output for function dp_overall_DP [Pa]

Modelica.Fluid.Dissipation.PressureLoss.StraightPipe.dp_overall_MFLOW

Information

Calculation of pressure loss in a straight pipe for overall flow regime of an incompressible and single-phase fluid flow only considering surface roughness.

Generally this function is numerically best used for the compressible case , where the pressure loss (dp) is known (out of pressures as state variable) in the used model and the corresponding mass flow rate (M_FLOW) has to be calculated. On the other hand the function dp_overall_DP is numerically best used for the incompressible case if the mass flow rate (m_flow) is known (as state variable) and the pressure loss (DP) has to be calculated. See more information.

Inputs

Name	Description
Constant inputs
IN_con	Input record for function dp_overall_MFLOW
Variable inputs
IN_var	Input record for function dp_overall_MFLOW
Input
dp	Pressure loss [Pa]

Outputs

Name	Description
M_FLOW	Output of function dp_overall_MFLOW [kg/s]

Modelica.Fluid.Dissipation.PressureLoss.StraightPipe.dp_overall_IN_con

Information

Parameters

Name	Description
Straight pipe
roughness	Choice of considering surface roughness
d_hyd	Hydraulic diameter [m]
L	Length [m]
K	Roughness (average height of surface asperities) [m]

Modelica.Fluid.Dissipation.PressureLoss.StraightPipe.dp_overall_IN_var

Information

Parameters

Name	Description
Fluid properties
eta	Dynamic viscosity of fluid [Pa.s]
rho	Density of fluid [kg/m3]

Modelica.Fluid.Dissipation.PressureLoss.StraightPipe.dp_turbulent_DP

Information

Calculation of pressure loss in a straight pipe for turbulent flow regime of an incompressible and single-phase fluid flow only considering surface roughness.

Generally this function is numerically best used for the incompressible case , where the mass flow rate (m_flow) is known (as state variable) in the used model and the corresponding pressure loss (DP) has to be calculated. On the other hand the function dp_turbulent_MFLOW is numerically best used for the compressible case if the pressure loss (dp) is known (out of pressures as state variable) and the mass flow rate (M_FLOW) has to be calculated. See more information.

Inputs

Name	Description
Constant inputs
IN_con	Input record for function dp_turbulent_DP
Variable inputs
IN_var	Input record for function dp_turbulent_DP
Input
m_flow	Mass flow rate [kg/s]

Outputs

Name	Description
DP	Output for function dp_turbulent_DP [Pa]

Modelica.Fluid.Dissipation.PressureLoss.StraightPipe.dp_turbulent_MFLOW

Information

Calculation of pressure loss in a straight pipe for turbulent flow regime of an incompressible and single-phase fluid flow only considering surface roughness.

Generally this function is numerically best used for the compressible case if the pressure loss (dp) is known (out of pressures as state variable) and the mass flow rate (M_FLOW) has to be calculated. On the other hand the function dp_turbulent_DP is numerically best used for the incompressible case , where the mass flow rate (m_flow) is known (as state variable) in the used model and the corresponding pressure loss (DP) has to be calculated. See more information.

Inputs

Name	Description
Constant inputs
IN_con	Input record for function dp_turbulent_MFLOW
Variable inputs
IN_var	Input record for function dp_turbulent_MFLOW
Input
dp	Pressure loss [Pa]

Outputs

Name	Description
M_FLOW	Mass flow rate [kg/s]

Modelica.Fluid.Dissipation.PressureLoss.StraightPipe.dp_turbulent_IN_con

Information

Parameters

Name	Description
Straight pipe
roughness	Choice of considering surface roughness
d_hyd	Hydraulic diameter [m]
L	Length [m]
K	Roughness (average height of surface asperities) [m]

Modelica.Fluid.Dissipation.PressureLoss.StraightPipe.dp_turbulent_IN_var

Information

Parameters

Name	Description
Fluid properties
eta	Dynamic viscosity of fluid [Pa.s]
rho	Density of fluid [kg/m3]

Modelica.Fluid.Dissipation.PressureLoss.StraightPipe.dp_twoPhaseOverall_DP

Information

Calculation of pressure loss for two phase flow in a horizontal or vertical straight pipe for an overall flow regime considering frictional, momentum and geodetic pressure loss.

Generally the pressure loss for two phase flow in a horizontal or a vertical straight pipe can be calculated for the following fluid flow regimes:

Horizontal fluid flow [(a) bubble flow, (b) stratified flow, (c) wavy flow, (d) slug flow, (e) annular flow]:

Vertical fluid flow [(a) bubble flow, (b) plug slug flow, (c) foam flow, (d) annular streak flow, (e) annular flow]:

See more information.

Inputs

Name	Description
Constant inputs
IN_con	Input record for function dp_twoPhaseOverall_DP
Variable inputs
IN_var	Input record for function dp_twoPhaseOverall_DP
Input
m_flow	Mass flow rate [kg/s]

Outputs

Name	Description
DP	Two phase pressure loss [Pa]

Modelica.Fluid.Dissipation.PressureLoss.StraightPipe.dp_twoPhaseOverall_IN_con

Information

Parameters

Name	Description
Choices
frictionalPressureLoss	Choice of frictional pressure loss approach
voidFractionApproach	Choice of void fraction approach
momentumPressureLoss	Considering momentum pressure loss
massFlowRateCorrection	Consider heterogeneous mass flow rate correction
geodeticPressureLoss	Considering geodetic pressure loss
Geometry
A_cross	Cross sectional area [m2]
perimeter	Wetted perimeter [m]
length	Length in fluid flow direction [m]
phi	Tilt angle to horizontal [rad]

Modelica.Fluid.Dissipation.PressureLoss.StraightPipe.dp_twoPhaseOverall_IN_var

Information

Parameters

Name	Description
Fluid properties
x_flow_end	Mass flow rate quality at end of length
x_flow_sta	Mass flow rate quality at start of length
rho_g	Density of gas [kg/m3]
rho_l	Density of liquid [kg/m3]
eta_g	Dynamic viscosity of gas [Pa.s]
eta_l	Dynamic viscosity of liquid [Pa.s]
sigma	Surface tension [N/m]
Input
x_flow	Mean mass flow rate quality over length