--- Welcome to the official ADCIRCWiki site! The site is currently under construction, with limited information. ---

For general information, see the ADCIRC site, ADCIRC FAQ, or the ADCIRC Wikipedia page. For model documentation not yet available on the wiki, see the ADCIRC site. New content is being continuously added to the ADCIRCWiki, and material from the main ADCIRC site will be gradually transitioned over to the wiki.

IM: Difference between revisions

From ADCIRCWiki
Jump to navigation Jump to search
No edit summary
No edit summary
Line 18: Line 18:
! Digit 6: GWCE mass matrix
! Digit 6: GWCE mass matrix
|-
|-
| 1
| 1 (default)
| 2DDI Kolar-Gray flux-based
| 2DDI, Kolar-Gray flux-based
| 2-part flux-based
| Non conservative
| 2-part velocity-based
| Integration by parts, velocity-based
| 2-part flux-based symmetrical
| Non conservative
| 2-part velocity-based symmetrical
| Corrected
| Consistent (semi-implicit), barotropic
|-
|-
| 2
| 2
| 2DDI 2-part flux-based
| 2DDI, 2-part flux-based
| row 2, cell 2
| Conservative form 1
| row 2, cell 3
| Integration by parts, flux-based
| row 2, cell 4
| Conservative form 1
| row 2, cell 5
| Original
| Lumped (explicit), barotropic
|-
|-
| 3
| 3
| 2DDI 2-part velocity-based
| 2DDI, 2-part velocity-based
| row 2, cell 2
| Conservative form 2
| row 2, cell 3
| Integration by parts, velocity-based symmetrical
| row 2, cell 4
| Conservative form 2
| row 2, cell 5
| -
| Lumped (explicit), baroclinic (''not yet implemented in ADCIRC release version'')
|-
|-
| 4
| 4
| 2DDI 2-part flux-based symmetrical
| 2DDI, 2-part flux-based symmetrical
| row 2, cell 2
| -
| row 2, cell 3
| Integration by parts, flux-based symmetrical
| row 2, cell 4
| -
| row 2, cell 5
| -
| -
|-
|-
| 5
| 5
| 2DDI 2-part velocity-based symmetrical
| 2DDI, 2-part velocity-based symmetrical
| row 2, cell 2
| -
| row 2, cell 3
| 2 Part, velocity-based (''not implemented'')
| row 2, cell 4
| -
| row 2, cell 5
| -
| -
|-
|-
| 6
| 6
| 3D Kolar-Gray flux-based
| 3D, Kolar-Gray flux-based
| row 2, cell 2
| -
| row 2, cell 3
| 2 Part, flux-based (''not implemented'')
| row 2, cell 4
| -
| row 2, cell 5
| -
| -
|}
|}



Revision as of 19:39, 2 February 2019

IM is an important parameter in the fort.15 file that defines numerical model formulation and dimension. Among other things, IM specifies whether ADCIRC is 2DDI or 3D, solution of the governing equations is implicit or explicit in space, and whether the model formulation is barotropic or baroclinic.

Shortcut IM Values

The most common combination of options used for simulation can be specified through the shortcut values

Six-digit IM Codes

For fine-grained control of various options in simulations six-digit codes for IM can be specified. Each digit represents a specific option regarding the formulation of certain terms or integration methods in the GWCE or momentum equations. The available options for each digit are specified below:

Value Digit 1: 2DDI/3D, Lateral Stress in GWCE[1] Digit 2: Advection in GWCE Digit 3: Lateral Stress in Momentum Digit 4: Advection in Momentum Digit 5: Area Integration in Momentum Digit 6: GWCE mass matrix
1 (default) 2DDI, Kolar-Gray flux-based Non conservative Integration by parts, velocity-based Non conservative Corrected Consistent (semi-implicit), barotropic
2 2DDI, 2-part flux-based Conservative form 1 Integration by parts, flux-based Conservative form 1 Original Lumped (explicit), barotropic
3 2DDI, 2-part velocity-based Conservative form 2 Integration by parts, velocity-based symmetrical Conservative form 2 - Lumped (explicit), baroclinic (not yet implemented in ADCIRC release version)
4 2DDI, 2-part flux-based symmetrical - Integration by parts, flux-based symmetrical - - -
5 2DDI, 2-part velocity-based symmetrical - 2 Part, velocity-based (not implemented) - - -
6 3D, Kolar-Gray flux-based - 2 Part, flux-based (not implemented) - - -

A common code combination is IM = 111112, which uses default options (same as IM = 0), but simulates in explicit mass-lumping mode. This is a useful alternative to the (default) semi-implicit consistent GWCE mass matrix mode, which requires a matrix solve increasing computational time and memory compared to the explicit mass-lumping mode, which as about twice as fast and scales to fewer grid nodes per computational core.[2]

References

  1. K.M. Dresback, R.L. Kolar, R.A. Luettich, Jr., On the Form of the Momentum Equation and Lateral Stress Closure Law in Shallow Water Modeling, in: Estuar. Coast. Model., American Society of Civil Engineers, Reston, VA, 2005: pp. 399–418. doi:10.1061/40876(209)23.
  2. S. Tanaka, S. Bunya, J.J. Westerink, C. Dawson, R.A. Luettich, Scalability of an Unstructured Grid Continuous Galerkin Based Hurricane Storm Surge Model, J. Sci. Comput. 46 (2011) 329–358. doi:10.1007/s10915-010-9402-1