错误提示及解决方法.docx

Diagnostics : Error Messages

Error Messages
This section summarizes the most common error messages and solver messages generated by COMSOL Multiphysics. All error messages are numbered and sorted in different categories according to the following table.
TABLE 2-1: ERROR MESSAGE CATEGORIES
NUMBERS
CATEGORY
1000–1999
Importing Models
2000–2999
Geometry Modeling
3000–3999
CAD Import
4000–4999
Mesh Generation
5000–5999
Point, Edge, Boundary, and Subdomain Specification
6000–6999
Assembly and Extended Mesh
7000–7999
Solvers
8000–8999
Postprocessing
9000–9999
General
For error messages that do not appear in the following lists, contact COMSOL’s support team for help.
2000–2999 Geometry Modeling

TABLE 2-2: GEOMETRY MODELING ERROR MESSAGES
ERROR NUMBER
ERROR MESSAGE
EXPLANATION
2118
Negative output from empty input
Incorrect Geometry M-file.
2119
Non scalar output from empty input
Incorrect Geometry M-file.
2120
Normal directions are inconsistent
Incorrect input data from STL/VRML import.
2138
Self intersections not supported
Curves resulting in self-intersections are not supported.
2140
Singular extrusions not supported
Error in input parameters.
2141
Singular revolutions not supported
The revolved mesh has a singularity at the z axis. If possible, create the cylinder using a 3D primitive or by revolving the geometry before meshing.
2146
Subdomain must bounded at least four boundary segments
Incorrect geometry for mapped mesh.
2147
Subdomain must bound one connected edge component only
Incorrect geometry for mapped mesh.
2190
Invalid radius or distance
Incorrect input parameters to fillet/chamfer.
2197
Operation resulted in empty geometry object
Geometry operation resulted in an empty geometry object which is not allowed. Make sure an empty geometry object is not created.
2209
Geometry to revolve may not cross axis of revolution
The axis of revolution and the geometry intersect. Check the dimension of the geometry and the definition of the axis for the revolution.

4000–4999 Mesh Generation

TABLE 2-3: MESH GENERATION ERROR MESSAGES
ERROR NUMBER
ERROR MESSAGE
EXPLANATION
4002
A degenerated tetrahedron was created
The mesh generator ran into numerical difficulties while creating tetrahedrons with a size based on user-controlled parameters. Causes could be too small and narrow subdomains relative to the rest of the geometry or exceedingly short boundary segments. Try to avoid creating small and narrow subdomains and very short boundary segments that are adjacent to longer boundary segments.
4003
A degenerated triangle was created
The mesh generator ran into numerical difficulties while creating triangles with a size based on user-controlled parameters. Causes could be too small and narrow subdomains relative to the rest of the geometry or exceedingly short boundary segments. Try to avoid creating small and narrow subdomains and very short boundary segments that are adjacent to longer boundary segments.
4012
Cannot create mapped mesh for this geometry
The geometry does not fulfill the topological requirements for a mapped mesh. Changes in input parameters or further subdomain division can possibly help this.
4026
Failed create matching edge discretizations
Cannot make mapped mesh with the given input parameters.
4029
Failed to insert point
Problems inserting point at given coordinate. Manually inserting a point there may help.
4031
Failed to respect boundary element on geometry edge
The mesh generator failed in making the elements compatible with the geometry object’s edges. The reason for this could be that the face mesh is too coarse or contains adjacent elements with large differences in scale. Another reason can be that some subdomains in the geometry are too narrow with respect to the rest of the geometry.
4032
Failed to respect boundary element on geometry face
See Error message 4031.
4044
Internal error boundary respecting
See Error message 4031.
4054
Invalid topology of geometry
The geometry object cannot be used for creating a mapped mesh. It must be subdivided.
4055
Isolated entities found
Entities that are not connected to the boundaries of a geometry objects is found. The mapped mesh generator does not support such isolated entities.
4119
Singular edge detected
The geometry object contains an edge of zero length.

6000–6999 Assembly and Extended Mesh

TABLE 2-4: ASSEMBLY AND EXTENDED MESH ERROR MESSAGES
ERROR NUMBER
ERROR MESSAGE
EXPLANATION
6008
Circular variable dependency detected
A variable has been defined in terms of itself, possibly in a circular chain of expression variables. Make sure that variable definitions are sound. Be cautious with equation variables in equations.
6063
Invalid degree of freedom name
The software does not recognize the name of a degree of freedom. Check the names of dependent variables that you have entered for the model. See also Error 7192.
6139
Wrong number of DOFs in initial value
The current solution or the stored solution has for some reason the wrong number of degrees of freedom, sometimes due to a change of the implementation of elements between two versions of the software. To overcome the problem, go to the Initial value area in the Solver Manager, and select Initial value expression. Then the initial value expressions is evaluated without using the current or stored solution.
6140
Wrong number of dofs in linearization point
The current solution or the stored solution has for some reason the wrong number of degrees of freedom, sometimes due to a change of the implementation of elements between two versions of the software. To overcome the problem, go to the Value of variables not solved for and linearization point area in the Solver Manager, and click the Use setting from Initial value frame button or the Zero button.
6163
Divide by zero
A property in the model contains a divisor that becomes zero. Check to make sure that division by zero does not occur in any expression or coefficient.
6164
Duplicate variable name
A variable name has two different definitions. For instance, the same variable name appears two or more times for a dependent variable, a constant, an expression variable, or a coupling variable. Remove or rename one of the variables.
6170
Failed to evaluate variable
An error occurred when evaluating the variable. The domains in which COMSOL Multiphysics tried to evaluate the variable are indicated. Also, the error message shows the expression that COMSOL Multiphysics was unable to evaluate. Make sure that you have defined the variables correctly in the indicated domains.
6176
Attempt to evaluate real logarithm of negative number
An expression contains log(a), where a becomes negative or zero. To make the logarithm well-defined, make sure that a>0. Often, a becomes only slightly negative (due to approximations in the solution process). Then, a possible solution is to use log(a+e), where e is a small constant. Another remedy is to use log(abs(a)). If you do want to have a complex logarithm, go to the Advanced tab of Solver Parameters and select the Use complex functions with real input check box.
6177
Matrix has zero on diagonal
When the equations have a structure such that the stiffness matrix (Jacobian matrix) has zeros on the diagonal, it is not possible to use the following linear system solvers/preconditioners/smoothers: all versions of SOR and Diagonal scaling (Jacobi). Try the Vanka preconditioner/smoother instead.
6188
Out of memory during assembly
The software ran out of memory during assembly of the finite element model. See error 7144 regarding general memory-saving tips.
6194
Attempt to evaluate non-integral power of negative number
An expression contains a^b, where a becomes negative and b is not an integer. To make the power well-defined, make sure that a>0. Often, a becomes only slightly negative (due to approximations in the solution process). Then, a possible solution is to use (a+e)^b, where e is a small constant. Another remedy is to use abs(a)^b. If you do want to have a complex number a^b, go to the Advanced tab of Solver Parameters and select Use complex functions with real input.
6199
Attempt to evaluate real square root of negative number
The model contains a sqrt (square root) function that takes the square root of a negative number. Either make sure that the square-root argument is nonnegative or select the Use complex functions with real input check box on the Advanced tab in the Solver Parameters dialog box.
6204
Undefined function call
An expression contains an undefined function name. Check that the function name is correct and that the function is in COMSOL Multiphysics’ or MATLAB’s path.
6206
Internal evaluation error: unexpected NaN encountered
Not-A-Number (NaN) appears unexpectedly. A possible cause is improperly defined coupling variables. As a first step, check that the definitions of the source and destination domains of any coupling variables or periodic boundary conditions are correct.
6245
Unsupported integration order
Integration order is too high. For triangular elements the order can be up to 10, and for tetrahedral elements the order can be up to 8. Find more information in the section “Numerical Quadrature” on page 505.
6259
Failed to evaluate variable Jacobian
An error occurred when evaluating the Jacobian of the indicated variable. The domains in which COMSOL Multiphysics tried to evaluate the variable are indicated. Make sure that you have defined the variable correctly in the indicated domains.

7000—7999 Solvers and Preconditioners

TABLE 2-5: SOLVER ERROR MESSAGES
ERROR NUMBER
ERROR MESSAGE
EXPLANATION
7001
Adaption only implemented for tetrahedral meshes
It is only possible to use adaptive mesh refinement in 3D for models using tetrahedral mesh elements. Either turn off adaptive mesh refinement or switch from brick or prism elements to tetrahedral elements.
7002
Adaption only implemented for triangular meshes
It is only possible to use adaptive mesh refinement in 2D for models using triangular mesh elements. Either turn off adaptive mesh refinement or switch from quadrilateral elements to triangular elements.
7022
Segregated solver steps do not involve all of solcomp
The groups for the segregated solver do not include all dependent variables. One reason for this error could be that some boundary conditions (for example, for laminar inflow in fluid-flow models) add dependent variables that are not initially in the model.
7043
Initial guess leads to undefined function value
This error message usually appears when you have set up an expression that returns “not a value,” that is, it is undefined, for the initial condition you have set. For instance, this happens if an expression contains a divisor that becomes zero or a logarithm of a negative value. To solve the problem, change the expression or the initial value so that the expression is well-defined when substituting the initial value of the variables. Also, watch out for warnings in the Log window.
7067
System matrix is zero
This error message appears if there are no volume elements in the mesh. In the case that you have a mapped surface mesh, try sweeping or extruding the surface mesh to get a volume mesh.
7069
Maximum number of linear iterations reached
The iterative linear system solver did not converge due to a bad initial guess or a bad preconditioner. Increase the limit on the number of linear iterations or use a better preconditioner. If possible, use a direct linear system solver.
7081
No parameter name given
The parametric solver does not find a name for the parameter. Check the Name of parameter edit field on the General page of the Solver Manager.
7092
Out of memory in Algebraic multigrid
The Algebraic multigrid solver/preconditioner ran out of memory. See error 7144 regarding general memory-saving tips.
7093
Out of memory during back substitution
The solver ran out of memory during back substitution. See error 7144 regarding general memory-saving tips.
7094
Out of memory during LU factorization
The solver ran out of memory during LU factorization. See error 7144 regarding general memory-saving tips.
7111
Singular matrix
The system matrix (Jacobian matrix or stiffness matrix) is singular, so the solver cannot invert it. Usually this means that the system is underdetermined. Check that all equations are fully specified and that the boundary conditions are appropriate. For instance, in a stationary model you usually need to have a Dirichlet condition on some boundary. A singular matrix could also occur if mesh elements are of too low quality. If the minimum element quality is less than 0.005 you might be in trouble. Another reason for this error message is that you have different element orders for two variables that are coupled by, for example, a weak constraint. Use the same element order for all variables that are coupled.
7136
Very ill-conditioned preconditioner. The relative residual is more than 1000 times larger than the relative tolerance
You need to improve the quality of the preconditioner to get an accurate solution. For the Incomplete LU preconditioner, lower the drop tolerance.
7144
Out of memory in adaptive solver
The adaptive solver ran out of memory. The adaptive mesh refinement has generated a too fine mesh. In general, when you run out of memory, try to use memory-efficient modeling techniques such as utilizing symmetries, solving models sequentially, and selecting memory-efficient solvers. See the chapter “Solving the Model” on page 377 in the COMSOL Multiphysics User’s Guide for more information. See also the COMSOL Installation and Operations Guide for information about system memory management.
7145
Out of memory in eigenvalue solver
The eigenvalue solver ran out of memory. See error 7144 regarding general memory-saving tips.
7146
Out of memory in stationary solver
The stationary solver ran out of memory. See error 7144 regarding general memory-saving tips.
7147
Out of memory in time-dependent solver
The time-dependent solver ran out of memory. See error 7144 regarding general memory-saving tips.
7192
Invalid degree of freedom name in manual scaling
The name of a dependent variable in the Manual scaling edit field on the Advanced page in the Solver Parameters dialog box does not match any of the dependent variables in the model.
7199
Reordering failed
One of the PARDISO reordering algorithms failed. Try a different reordering algorithm or try turning off row preordering.
7248
Undefined value found
See the explanation of error 7043 for some possible reasons as to why this error number appears. In most situations you get a more detailed description of the error by pressing the Details button.
7297
Undefined value found
This error number appears if one of the linear system solvers enco