Engee documentation

Convective Heat Transfer

Convective heat transfer.

blockType: AcausalFoundation.Thermal.Elements.Convection

controlled convective heat transfer

Convective Heat Transfer

Path in the library:

/Physical Modeling/Fundamental/Thermal/Elements/Convective Heat Transfer

convective heat transfer 1

Controlled Convective Heat Transfer

Path in the library:

/Physical Modeling/Fundamental/Thermal/Elements/Variable Convective Heat Transfer

Description

Block Convective Heat Transfer It is a convective transfer of heat between two bodies, that is, heat transfer through the movement of matter. The process is described by the Newton-Richman law:

where

  • — heat flow;

  • — heat transfer coefficient;

  • — surface area;

  • and — temperatures of two bodies .

A and B are thermal ports corresponding to different bodies. The heat flow is positive if it flows from A to B.

Variables

Use the parameter group Initial Targets to set the priority and initial target values for the block parameter variables before modeling. For more information, see Configuring physical blocks using target values.

Ports

Conserving

# A — Body A
heat

Details

Thermal port corresponding to body A.

Program usage name

port_a

# B — body B
heat

Details

Thermal port corresponding to body B.

Program usage name

port_b

Input

# K — heat transfer coefficient control signal, W/(K*m2)
scalar

Details

The input signal for controlling the heat transfer coefficient. The signal value cannot fall below the limit set by the parameter Minimum heat transfer coefficient. A signal less than this value is equated to Minimum heat transfer coefficient.

Dependencies

To use this port, set the parameter Convection type value Variable.

Data types

Float64
Complex numbers support

I don’t

Parameters

Parameters

# Convection type — type of heat transfer coefficient
Fixed | Variable

Details

Type of heat transfer coefficient:

  • Fixed — the heat transfer coefficient set by the parameter Heat transfer coefficient, remains constant during simulation.

  • Variable — input signal on the port K sets the heat transfer coefficient, which can change during simulation. Parameter Minimum heat transfer coefficient sets the lower limit of the heat transfer coefficient.

Values

Fixed | Variable
Default value

—
Program usage name

type
Evaluatable

No

# Area — heat exchange area
m^2 | um^2 | mm^2 | cm^2 | km^2 | in^2 | ft^2 | yd^2 | mi^2 | ha | ac

Details

Heat exchange surface area.

Units

m^2 | um^2 | mm^2 | cm^2 | km^2 | in^2 | ft^2 | yd^2 | mi^2 | ha | ac
Default value

1e-4 m^2
Program usage name

area
Evaluatable

Yes

# Heat transfer coefficient — heat transfer coefficient
W/(m^2*K) | Btu_IT/(hr*ft^2*deltadegR)

Details

Heat transfer coefficient.

Dependencies

To use this parameter, set for the parameter Convection type meaning Fixed.

Units

W/(m^2*K) | Btu_IT/(hr*ft^2*deltadegR)
Default value

20.0 W/(m^2*K)
Program usage name

h
Evaluatable

Yes

# Minimum heat transfer coefficient — the lower limit of the heat transfer coefficient
W/(m^2*K) | Btu_IT/(hr*ft^2*deltadegR)

Details

The lower limit of the convective heat transfer coefficient.

Input signal on the port K It is saturated at this value to prevent a further decrease in the heat transfer coefficient.

Dependencies

To use this parameter, set for the parameter Convection type meaning Variable.

Units

W/(m^2*K) | Btu_IT/(hr*ft^2*deltadegR)
Default value

0.001 W/(m^2*K)
Program usage name

h_min
Evaluatable

Yes

Examples