Modelica.Fluid.Dissipation.Utilities.Records.PressureLoss

Information

Package Content

Name	Description
Bend	Input for bend
Geometry	Input for several geometries of internal flow
Orifice	Input for orifice
PressureLossInput	Input for pressure loss calculation
StraightPipe	Input for straight pipe
Tjunction	Input for T-junction
Diffuser	Input for diffuser
EdgedBend	Input for bend
SuddenChange	Input for sudden change of diameter

Modelica.Fluid.Dissipation.Utilities.Records.PressureLoss.Bend

Information

Parameters

Name	Description
Bend
d_hyd	Hydraulic diameter [m]
delta	Angle of turning [rad]
K	Roughness (absolute average height of surface asperities) [m]
R_0	Curvature radius [m]

Modelica.Fluid.Dissipation.Utilities.Records.PressureLoss.Geometry

Information

Parameters

Name	Description
Channel
geometry	Choice of geometry for internal flow
K	Roughness (average height of surface asperities) [m]
L	Length [m]
Annular cross sectional area
d_ann	Small diameter [m]
D_ann	Large diameter [m]
Circular cross sectional area
d_cir	Internal diameter [m]
Elliptical cross sectional area
a_ell	Half length of long base line [m]
b_ell	Half length of short base line [m]
Rectangular cross sectional area
a_rec	Horizontal length [m]
b_rec	Vertical length [m]
a_tri	Length of base line [m]
Triangle cross sectional area
h_tri	Height to top angle perpendicular to base line [m]
beta	Top angle [rad]

Modelica.Fluid.Dissipation.Utilities.Records.PressureLoss.Orifice

Information

Parameters

Name	Description
Orifice
A_0	Cross sectional area of vena contraction [m2]
C_0	Perimeter of vena contraction [m]
A_1	Large cross sectional area of orifice [m2]
C_1	Large perimeter of orifice [m]
L	Length of vena contraction [m]

Modelica.Fluid.Dissipation.Utilities.Records.PressureLoss.PressureLossInput

Information

Parameters

Name	Description
Input
target	Target variable of calculation
dp	Pressure loss [Pa]
m_flow	Mass flow rate [kg/s]

Modelica.Fluid.Dissipation.Utilities.Records.PressureLoss.StraightPipe

Information

Parameters

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

Modelica.Fluid.Dissipation.Utilities.Records.PressureLoss.Tjunction

Information

Parameters

Name	Description
T-junction
united_converging_crossection	true == A_cross_total = 2*A_cross_branch | false == A_cross_total > 2*A_cross_branch
velocity_reference_branches	true == pressure loss coefficents w.r.t. velocity in each passage | false == w.r.t. velocity in total passage
alpha	Angle of branching
d_hyd[3]	Hydraulic diameter of passages [side,straight,total] [m]
Restrictions
m_flow_min	Restriction for smoothing at reverse fluid flow [kg/s]
v_max	Restriction for maximum fluid flow velocity [m/s]
zeta_TOT_max	Restriction for maximum value of pressure loss coefficient

Modelica.Fluid.Dissipation.Utilities.Records.PressureLoss.Diffuser

Information

Parameters

Name	Description
Diffuser
alpha	Diffuser diverging angle [rad]
A_1	Small constant cross sectional area before diffuser section [m2]
A_2	Large constant cross sectional area after diffuser section [m2]
C_1	Small perimeter before diffuser section [m]
C_2	Large perimeter after diffuser section [m]
L_1	Length of straight pipe before diffuser section [m]
L_2	Length of straight pipe after diffuser section [m]
L_d	Lenght of diffuser section (parallel to bulk fluid flow) [m]
Numerical aspects
dp_small	Linearisation for a pressure loss smaller then dp_small [Pa]
zeta_TOT_min	Minimal pressure loss coefficient for infinite Reynolds number
zeta_TOT_max	Maximum pressure loss coefficient for Reynolds number approaching zero

Modelica.Fluid.Dissipation.Utilities.Records.PressureLoss.EdgedBend

Information

Parameters

Name	Description
Bend
d_hyd	Hydraulic diameter [m]
delta	Angle of turning [rad]
K	Roughness (absolute average height of surface asperities) [m]

Modelica.Fluid.Dissipation.Utilities.Records.PressureLoss.SuddenChange

Information

Parameters

Name	Description
Orifice
A_1	Small cross sectional area of orifice [m2]
A_2	Large cross sectional area of orifice [m2]
C_1	Small perimeter of orifice [m]
C_2	Large perimeter of orifice [m]