CRYOLIB.PIPE

COMPONENT PIPE IS_A FluidChannel

ICON:

DESCRIPTION:
Pipe 0D

DOCUMENTATION:

This component represents a 0D physical pipe that exchanges heat with the wall and the environment. It inherits from the component FluidChannel.

CONSTRUCTION PARAMETERS:

NAME	TYPE	DEFAULT	DESCRIPTION	UNITS
Heat_Transfer	ENUM HeatTransfer	hc_cste	Heat transfer coefficient calculation
PIPE_DN	ENUM PIPEDN	DN50	Pipe size
mat	ENUM THERMAL.Material	SS_304	Material of the pipe

PORTS:

NAME	TYPE	PARAMETERS	DIRECTION	CARDINALITY	DESCRIPTION
f_in	fluid		IN
f_out	fluid		OUT

DATA:

NAME	TYPE	DEFAULT	RANGE	DESCRIPTION	UNITS
D_out	REAL	30		External diameter defined by the user if DN_NONE	mm
Extra_M	REAL	0		Additional mass in contact with the pipe	kg
L	REAL	1.1		Length	m
Po	REAL	1		Initial pressure	bar
Q_d	REAL	0		Nominal radiation loss	W
T_env	REAL	300		Temperature of the environment for radiation losses	K
To	REAL	300		Initial temperature	K
Tw_d	REAL	300		Nominal temperature of the wall	K
dz	REAL	0		Difference of altitude for hydrostatic pressure (zin - zout)	m
e	REAL	1		Thickness	mm
hc_dat	REAL	100		Heat transfer coefficient if constant	J/kg
rough	REAL	0.0005		Roughness of pipe	m
z_bottom	REAL	0		Elevation of the base w.r.t. the coordinate system set by the user	m

DECLS:

NAME	TYPE	INITIAL	RANGE	DESCRIPTION	UNITS
A	REAL			Area	m^2
Cpw	REAL			Wall specific heat capacity	J/(kg�K)
D_ext	REAL			External Diameter	mm
D_int	REAL			Internal Diameter	mm
K	REAL			Pressure drop coefficient	-
M	REAL			Total mass inside the volume	kg
Mw	REAL			Wall mass	kg
Nu	REAL			Nusselt Number	-
P	REAL			Pressure	bar
Pr	REAL			Prandtl Number	-
Qrad	REAL			Radiation heat loss	W
Re	REAL			Reynolds Number	-
Sw	REAL			Wall Surface	m^2
T	REAL			Fluid Temperature	K
Tf	REAL			Film temperature	K
Tw	REAL			Wall temperature	K
V	REAL			Internal Volume	m^3
cond	REAL			Viscosity	W/(m�K)
cp	REAL			Specific heat	J/(kg�K)
dP_loss	REAL				bar
drho_dh	REAL			Partial derivative of the density with respect to the specific enthalpy at constant pressure
drho_dp	REAL			Partial derivative of density with respect to the pressure at constant specific enthalpy (J m^3 / kg^2)	J m^3 / kg^2
error_flag	INTEGER
fr	REAL			Friction factor	-
h	REAL			Enthalpy	J/kg
h_g	REAL			Gas enthalpy	J/kg
h_l	REAL			Liquid enthalpy	J/kg
hc	REAL			Heat transfer coefficient	W/(m^2�K)
hf	REAL			Film enthalpy	J/kg
ier	INTEGER			Error index of thermodynamic function calls	-
ier2	INTEGER			Error index of thermodynamic function calls	-
m	REAL			Mass flow	kg/s
phase	ENUM FLUID_PROP.Phase
q	REAL				W
qn	REAL			Artifitial dissipation coefficient	Pa
rho	REAL			Density	kg/m^3
rho_g	REAL			Gas density	kg/m^3
rho_l	REAL			Liquid density	kg/m^3
rhow	REAL			Wall density	kg/m^3
u	REAL			Specific internal energy	J/kg
vel	REAL			Speed	m/s
visc	REAL				Pa�s
vsound	REAL			Speed of sound	m/s
x	REAL			Quality	-

FORMULATION:

FluidChannel formulation:

It transmits information from the inlet port to the outlet port about the working fluid that is being used in the fluid loop, the calculation option (real fluid) and checks if there is a working fluid defined in the model.

Pipe formulation:

At inlet and outlet, this component receives as input the following flow variables from the ports f_in and f_out: massflow m and total enthalpic flow mh. The equations governing the flow within this component are solved numerically to retrieve the profiles of all the relevant flow variables.

The port pressures are reconstructed from the pipe pressure and half a pressure drop due to the friction.

Mass conservation equation

where:

V is the volume of the pipe

ρ is the density of the fluid in the pipe

�is the massflow in the inlet port

�is the massflow in the outlet port

Energy conservation equation

Where u is the internal energy and h enthalpy.

Calculation of the friction factor

Friction factor is calculated using the hdc_fric() function from the FLUID_PROP library (see the FLUID_PROP manual for more information).

Document generated automatically with EcosimPro Version: 5.4.14 Date: 2015:02:02 Time: 12:52:59