modelEdgedBend

Edged bend flow model

Extends from Modelica.Fluid.Dissipation.Utilities.Icons.PressureLoss.Bend_i (Icon for bend), Modelica.Fluid.Interfaces.PartialPressureLoss (Base flow model for pressure loss functions with the same area at port_a and at port_b).

Information

This component models an edged bend in the overall flow regime for incompressible and single-phase fluid flow through circular cross sectional area considering surface roughness. It is expected that also compressible fluid flow can be handled up to about Ma = 0.3. It is assumed that neither mass nor energy is stored in this component. In the model basically a function is called to compute the mass flow rate as a function of pressure loss for an edged bend. Also the inverse of this function is defined, and a tool might use this inverse function instead, in order to avoid the solution of a nonlinear equation.

The details of the model are described in the documentation of the underlying function.

Parameters

TypeNameDefaultDescription
Modelica.Fluid.Fittings.BaseClasses.Bends.EdgedBend.GeometrygeometryGeometry of curved bend
Assumptions
BooleanallowFlowReversal (from PartialTwoPort)system.allowFlowReversal= true to allow flow reversal, false restricts to design direction (port_a -> port_b)
Advanced
Medium.AbsolutePressuredp_start (from PartialTwoPortTransport)0.01*system.p_startGuess value of dp = port_a.p - port_b.p
Medium.MassFlowRatem_flow_start (from PartialTwoPortTransport)system.m_flow_startGuess value of m_flow = port_a.m_flow
Medium.MassFlowRatem_flow_small (from PartialTwoPortTransport)if system.use_eps_Re then system.eps_m_flow*system.m_flow_nominal else system.m_flow_smallSmall mass flow rate for regularization of zero flow
Advanced › Diagnostics
Booleanshow_T (from PartialTwoPortTransport)true= true, if temperatures at port_a and port_b are computed
Booleanshow_V_flow (from PartialTwoPortTransport)true= true, if volume flow rate at inflowing port is computed

Connectors

TypeNameDefaultDescription
Modelica.Fluid.Interfaces.FluidPort_aport_a (from PartialTwoPort)Fluid connector a (positive design flow direction is from port_a to port_b)
Modelica.Fluid.Interfaces.FluidPort_bport_b (from PartialTwoPort)Fluid connector b (positive design flow direction is from port_a to port_b)

Components

TypeNameDefaultDescription
Modelica.Fluid.Systemsystem (from PartialTwoPort)System wide properties
Medium.MassFlowRatem_flow (from PartialTwoPortTransport)Mass flow rate in design flow direction
SI.Pressuredp (from PartialTwoPortTransport)Pressure difference between port_a and port_b (= port_a.p - port_b.p)
SI.VolumeFlowRateV_flow (from PartialTwoPortTransport)m_flow/Modelica.Fluid.Utilities.regStep(m_flow, Medium.density(state_a), Medium.density(state_b), m_flow_small)Volume flow rate at inflowing port (positive when flow from port_a to port_b)
Medium.Temperatureport_a_T (from PartialTwoPortTransport)Modelica.Fluid.Utilities.regStep(port_a.m_flow, Medium.temperature(state_a), Medium.temperature(Medium.setState_phX(port_a.p, port_a.h_outflow, port_a.Xi_outflow)), m_flow_small)Temperature close to port_a, if show_T = true
Medium.Temperatureport_b_T (from PartialTwoPortTransport)Modelica.Fluid.Utilities.regStep(port_b.m_flow, Medium.temperature(state_b), Medium.temperature(Medium.setState_phX(port_b.p, port_b.h_outflow, port_b.Xi_outflow)), m_flow_small)Temperature close to port_b, if show_T = true