PCONTHT
Bulk Data Entry Defines conductance for CONTACT elements in heat transfer analysis.
Format
| (1) | (2) | (3) | (4) | (5) | (6) | (7) | (8) | (9) | (10) |
|---|---|---|---|---|---|---|---|---|---|
| PCONTHT | PID | KCHTC | KOHTC | TPID | TCID |
Examples
| (1) | (2) | (3) | (4) | (5) | (6) | (7) | (8) | (9) | (10) |
|---|---|---|---|---|---|---|---|---|---|
| PCONTHT | 2 | 200.0 |
Contact with automatic determination of KCHTC:
| (1) | (2) | (3) | (4) | (5) | (6) | (7) | (8) | (9) | (10) |
|---|---|---|---|---|---|---|---|---|---|
| PCONTHT | 2 | AUTO |
Minimum data required to request pressure based contact HTC:
| (1) | (2) | (3) | (4) | (5) | (6) | (7) | (8) | (9) | (10) |
|---|---|---|---|---|---|---|---|---|---|
| PCONTHT | 2 | 10 |
Definitions
| Field | Contents | SI Unit Example |
|---|---|---|
| PID | Property identification number. Must match with a
PID of a PCONT Bulk Data
Entry. 1 No default (Integer > 0) |
|
| KCHTC | Contact Heat Transfer Coefficient (HTC) for the
closed contact. 2 No default (Real ≥ 0.0 or AUTO) |
|
| KOHTC | Contact Heat Transfer Coefficient (HTC) for the
open contact. 2 Default = 10-14 * KCHTC (Real ≥ 0.0). This default is also set when KOHTC =0. |
|
| TPID | Identification number of a
TABLED# entry. This table
specifies conductance per unit contact area
(Contact HTC) based on contact pressure. 3
4 Default = 0 (Integer > 0) |
|
| TCID | Identification number of a
TABLED# entry. This table
specifies conductance per unit contact area
(Contact HTC) based on contact clearance. 3
4
5 Default = 0 (Integer > 0) |
Comments
- PCONTHT provides Conductance
per unit area for CONTACT elements. The PID of a
PCONTHT Bulk Data Entry should match the PID of an
existing PCONT Bulk Data Entry.
Conductance per unit area is in the same unit as heat transfer coefficients, which is also called contact HTC. Total conductance is calculated by the product of contact HTC and contact area.
- KCHTC and
KOHTC represent Contact HTC values for closed and open contacts.
Theoretically, while higher Contact HTC values enforce a perfect conductor, excessively high
values may cause poor conditioning of the conductance matrix. If such conditions are
observed, it may be beneficial to reduce the value of Contact HTC, or use clearance and
pressure based Contact HTC via TCID and TPID. To facilitate reasonable values for KCHTC, automatic calculation is supported, specifically:
- Option KCHTC=AUTO determines the value of KCHTC for each contact element using the contact HTC values of surrounding elements.
- TPID points to a TABLED# entry that specifies conductance per unit contact area (Contact HTC) based on contact pressure. Total conductance is the product of table value and actual contact area. TPID is used when Thermal Contact Analysis uses STATSUB(STRUCTURE) to reference the Contact status from a static subcase. TPID overrides KCHTC for coupled thermal contact analysis.
- TCID points to a TABLED# entry that specifies conductance per unit contact area based on contact clearance. TCID overrides KOHTC for coupled thermal contact analysis, where nonlinear static subcase provides contact status for thermal contact. TPID can be specified together with TCID. When TPID is specified together with TCID, contact HTC is determined from the table with TCID for open contact (overrides KOHTC), and from the table with TPID for closed contact. TCID overrides KCHTC for closed contact if TPID is not present.
- For clearance-based Contact HTC table look-up, Contact HTC is linearly interpolated within the table range (which should start from zero clearance), and it becomes zero when extrapolated outside the table range.
- PCONTHT is not supported for surface-to-surface contact (DISCRET=S2S on CONTACT/TIE).
- For CONTACT interfaces without PCONT, PCONTHT is not required. Thermal Contact HTC values based on KCHTC=AUTO will be utilized in such cases.
- Thermal-structural analysis problems involving contact are fully coupled since contact/gap status changes thermal conductivity. Refer to Contact-based Thermal Analysis in the User Guide for more information.
- Thermal contact with FREEZE status uses the actual contact status (open or closed) based on geometry. For open contact, TCID overrides KOHTC. For closed contact without TPID, TCID at zero clearance overrides KCHTC. For fully coupled thermal contact with TPID, TPID overrides KCHTC.
- Thermal Contact Analysis via PCONTHT and PGAPHT is supported for Linear Steady-State Heat Transfer, Linear Transient Heat Transfer, Nonlinear Steady-State Heat Transfer, and Nonlinear Transient Heat Transfer analyses. Thermal Contact is also supported for One-Step Thermal Transient Stress Analysis (OSTTS).
- This card is represented as a property in HyperMesh.