Difference between revisions of "Natural convection in 3D irregular domain"

From Medusa: Coordinate Free Mehless Method implementation
Jump to: navigation, search
Line 16: Line 16:
 
[[File:DVD_3D.png|400px]]
 
[[File:DVD_3D.png|400px]]
 
[[File:DVD_3D_irreg.png|400px]]
 
[[File:DVD_3D_irreg.png|400px]]
 +
 +
{| class="wikitable"
 +
!
 +
! style="text-align: center;" | Ra
 +
! v_{max}
 +
!
 +
!
 +
! x
 +
!
 +
!
 +
! u_{max}
 +
!
 +
!
 +
! y
 +
!
 +
!
 +
|-
 +
|
 +
|
 +
| present
 +
| ref a
 +
| ref b
 +
| present
 +
| ref a
 +
| ref b
 +
| present
 +
| ref a
 +
| ref b
 +
| present
 +
| ref a
 +
| ref b
 +
|-
 +
| 2D
 +
| 10^6
 +
| 0.2628
 +
| 0.2604
 +
| 0.2627
 +
| 0.0378
 +
| 0.0380
 +
| 0.0390
 +
| 0.0781
 +
| 0.0765
 +
| 0.0782
 +
| 0.8476
 +
| 0.8510
 +
| 0.0390
 +
|-
 +
|
 +
| 10^7
 +
| 0.2633
 +
| 0.2580
 +
| 0.2579
 +
| 0.0226
 +
| 0.0230
 +
| 0.0210
 +
| 0.0588
 +
| 0.0547
 +
| 0.0561
 +
| 0.8705
 +
| 0.8880
 +
| 0.0210
 +
|-
 +
|
 +
| 10^8
 +
| 0.2557
 +
| 0.2587
 +
| 0.2487
 +
| 0.0149
 +
| 0.0110
 +
| 0.0090
 +
| 0.0314
 +
| 0.0379
 +
| 0.0331
 +
| 0.9189
 +
| 0.9430
 +
| 0.0090
 +
|-
 +
| 3D
 +
| 10^4
 +
| 0.2495
 +
| 0.2218
 +
| 0.2252
 +
| 0.8500
 +
| 0.8873
 +
| 0.8833
 +
| 0.2435
 +
| 0.1968
 +
| 0.2013
 +
| 0.1611
 +
| 0.1799
 +
| 0.1833
 +
|-
 +
|
 +
| 10^5
 +
| 0.2545
 +
| 0.2442
 +
| 0.2471
 +
| 0.9402
 +
| 0.9317
 +
| 0.9353
 +
| 0.1564
 +
| 0.1426
 +
| 0.1468
 +
| 0.1447
 +
| 0.1493
 +
| 0.1453
 +
|-
 +
|
 +
| 10^6
 +
| 0.2564
 +
| 0.2556
 +
| 0.2588
 +
| 0.9614
 +
| 0.9653
 +
| 0.9669
 +
| 0.0841
 +
| 0.0816
 +
| 0.0841
 +
| 0.1435
 +
| 0.1403
 +
| 0.1443
 +
|}

Revision as of 16:30, 18 May 2019

The classical De Vahl Davis natural convection test can be extended to 3D. In below figures steady state temperature contour and velocity quiver plots for Ra=10^6 case in 3D are presented. A more quantitative analysis is done by comparing characteristic values, i.e.\ peak positions and values of cross section velocities, with data available in literature~\cite{fusegi1991numerical}. We analyze six different cases, namely \textup{Ra} = 10^6,10^7,10^8 in 2D, and \textup{Ra} = 10^4,10^5,10^6 in 3D. The comparison in presented in~\cref{tab:ff-data}.

All spatial operators are discretized using RBF-FD with r^3 PHS radial basis functions, augmented with monomials up to order 2, with the closest 25 nodes used as a stencil. For the time discretization time step \Delta t=10^{-3} was used for all cases. Nodal distance h=0.01 is used for simulations in 2D and h=0.25 for simulations in 3D. Boundaries with Neumann boundary conditions are additionally treated with ghost nodes Ghost nodes (theory).

DVD 3D.png DVD 3D irreg.png

Ra v_{max} x u_{max} y
present ref a ref b present ref a ref b present ref a ref b present ref a ref b
2D 10^6 0.2628 0.2604 0.2627 0.0378 0.0380 0.0390 0.0781 0.0765 0.0782 0.8476 0.8510 0.0390
10^7 0.2633 0.2580 0.2579 0.0226 0.0230 0.0210 0.0588 0.0547 0.0561 0.8705 0.8880 0.0210
10^8 0.2557 0.2587 0.2487 0.0149 0.0110 0.0090 0.0314 0.0379 0.0331 0.9189 0.9430 0.0090
3D 10^4 0.2495 0.2218 0.2252 0.8500 0.8873 0.8833 0.2435 0.1968 0.2013 0.1611 0.1799 0.1833
10^5 0.2545 0.2442 0.2471 0.9402 0.9317 0.9353 0.1564 0.1426 0.1468 0.1447 0.1493 0.1453
10^6 0.2564 0.2556 0.2588 0.9614 0.9653 0.9669 0.0841 0.0816 0.0841 0.1435 0.1403 0.1443
Retrieved from "http://e6.ijs.si/medusa/wiki/index.php?title=Natural_convection_in_3D_irregular_domain&oldid=2518"