[sandy]

Hi guys, when I import my gambit .neu file into OpenFOAM, I check the mesh is OK. However, after I change the frontandback into empty (2D mesh) and check the mesh again, I get error message as follow:

/*---------------------------------------------------------------------------*\
| ========= | |
| \\ / F ield | OpenFOAM: The Open Source CFD Toolbox |
| \\ / O peration | Version: 1.5 |
| \\ / A nd | Web: http://www.OpenFOAM.org |
| \\/ M anipulation | |
\*---------------------------------------------------------------------------*/
Exec : checkMesh
Date : Aug 07 2009
Time : 01:55:47
Host : localhost.localdomain
PID : 5190
Case : /root/OpenFOAM/root-1.5/run/tutorials/LesInterPhaseChangeFoam/Hydrofoil/Sixdegree
nProcs : 1

// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
Create time

Create polyMesh for time = constant

Time = constant

Mesh stats
points: 91414
internal points: 0
faces: 181229
internal faces: 89815
cells: 45174
boundary patches: 6
point zones: 0
face zones: 0
cell zones: 0

Number of cells of each type:
hexahedra: 45174
prisms: 0
wedges: 0
pyramids: 0
tet wedges: 0
tetrahedra: 0
polyhedra: 0

Checking topology...
Boundary definition OK.
Point usage OK.
Upper triangular ordering OK.
Face vertices OK.
Number of regions: 1 (OK).

Checking patch topology for multiply connected surfaces ...
Patch Faces Points Surface topology
inlet 103 208 ok (non-closed singly connected)
outlet 158 318 ok (non-closed singly connected)
up 237 476 ok (non-closed singly connected)
down 236 474 ok (non-closed singly connected)
frontandback 90348 91414 ok (non-closed singly connected)
foil 332 664 ok (non-closed singly connected)

Checking geometry...
Overall domain bounding box (-10 -10 0) (30 10 0.007)
Mesh (non-empty) directions (1 1 0)
Mesh (non-empty, non-wedge) dimensions 2
***Number of edges not aligned with or perpendicular to non-empty directions: 38113
<<Writing 76226 points on non-aligned edges to set nonAlignedEdges
Boundary openness (-8.9509e-24 9.15928e-22 -1.31298e-19) OK.
Max cell openness = 2.56232e-16 OK.
Max aspect ratio = 287.879 OK.
Minumum face area = 2.19292e-05. Maximum face area = 0.452831. Face area magnitudes OK.
Min volume = 2.41268e-07. Max volume = 0.00316982. Total volume = 5.29651. Cell volumes OK.
Mesh non-orthogonality Max: 39.8412 average: 5.87407
Non-orthogonality check OK.
Face pyramids OK.
Max skewness = 0.763965 OK.

Failed 1 mesh checks.

End
==============================

What's wrong with it? Could somebody help me out? Thanks a lot.