CurvedBend

Curved bend flow model

Diagram

Information

This information is part of the Modelica Standard Library maintained by the Modelica Association.

This component models a curved 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 a curved 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 (7)

allowFlowReversal

Value: system.allowFlowReversal

Type: Boolean

Description: = true to allow flow reversal, false restricts to design direction (port_a -> port_b)

dp_start

Value: 0.01 * system.p_start

Type: AbsolutePressure (Pa)

Description: Guess value of dp = port_a.p - port_b.p

m_flow_start

Value: system.m_flow_start

Type: MassFlowRate (kg/s)

Description: Guess value of m_flow = port_a.m_flow

m_flow_small

Value: if system.use_eps_Re then system.eps_m_flow * system.m_flow_nominal else system.m_flow_small

Type: MassFlowRate (kg/s)

Description: Small mass flow rate for regularization of zero flow

show_T

Value: true

Type: Boolean

Description: = true, if temperatures at port_a and port_b are computed

show_V_flow

Value: true

Type: Boolean

Description: = true, if volume flow rate at inflowing port is computed

geometry

Value:

Type: Geometry

Description: Geometry of curved bend

Connectors (2)

port_a

Type: FluidPort_a

Description: Fluid connector a (positive design flow direction is from port_a to port_b)

port_b

Type: FluidPort_b

Description: Fluid connector b (positive design flow direction is from port_a to port_b)

Components (5)

system

Type: System

Description: System wide properties

state_a

Type: ThermodynamicState

Description: state for medium inflowing through port_a

state_b

Type: ThermodynamicState

Description: state for medium inflowing through port_b

state_dp_small

Type: ThermodynamicState

Description: Medium state to compute dp_small

geometry

Type: Geometry

Description: Geometry of curved bend