# PCONV

Bulk Data Entry Defines a free convection boundary condition properties.

## Format

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
PCONV PCONID MID FORM EXPF FTYPE H1

## Definitions

Field Contents SI Unit Example
PCONID Convection property identification number of a PCONV card.

No default (Integer > 0)

MID Material property identification number of MAT4 card.

(Integer > 0)

Defaults:

If FTYPE = 3, Default = Blank

If FTYPE ≠ 3, No default

FORM Types of formula used for free convection and, also to define the reference temperature definition for temperature-dependent convection coefficient lookup. 3

If 0, 10, or 20, $\text{q}=\text{H}*{\left(\text{T}-\text{TAMB}\right)}^{\text{EXPF}}*\left(\text{T}-\text{TAMB}\right)$

If 1, 11, or 21 $\text{q}=\text{H}*\left({\text{T}}^{\text{EXPF}}-{\text{TAMB}}^{\text{EXPF}}\right)$

Where, $\text{T}$ is grid temperature and $\text{TAMB}$ is the ambient temperature.

Default = 0 (Integer)

EXPF Free convection exponent.

If FORM = 0, 10, or 20, EXPF = 0.0 for linear convection.

If FORM = 1, 11, or 21, EXPF = 1.0 for linear convection.

Therefore, linear convection formula is: $\text{q}=\text{H}*\left(\text{T}-\text{TAMB}\right)$

FTYPE Convection Coefficient definition type.
0
The Convection Coefficient is specified on the MAT4 Bulk Data Entry referenced on the MID field
3
The Convection Coefficient is specified in the H1 field. The Convection Coefficient on the MAT4 Bulk Data Entry referenced in the MID field is ignored.

No default (Integer)

H1 Free Convection Coefficient value (for FTYPE=3).

Defines the Free Convection Coefficient value, if FTYPE=3.

No default (Real ≥ 0.0)

1. Every CONV card must refer a PCONV card.
2. Heat transfer coefficient (H) is specified on MAT4 card with MID.
3. In Nonlinear Heat Transfer, to define the reference temperature definition for temperature-dependent convection coefficient lookup, the FORM field can be used as:
FORM
Reference Temperature Description
0 or 1 (Default)
Reference Temperature is the average of:
• Element grid point temperatures (average), and
• Ambient point temperatures (average)
10 or 11
Reference temperature is the surface temperature (average of element grid point temperatures)
20 or 21
Reference temperature is the ambient temperature (average of ambient point temperatures).
4. This card is represented as a group in HyperMesh.