错误提示及解决方法

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 The revolved mesh has a singularity at the z axis. If

supported 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 Incorrect geometry for mapped mesh.

one connected edge

component only

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 The axis of revolution and the geometry intersect.

not cross axis of Check the dimension of the geometry and the

revolution 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 The geometry does not fulfill the topological requirements

mapped mesh for for a mapped mesh. Changes in input parameters or further

this geometry 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 The mesh generator failed in making the elements

boundary element

compatible with the geometry object’s edges. The reason

on geometry edge 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 See Error message 4031.

boundary element

on geometry face

4044 Internal error

boundary

respecting

See Error message 4031.

4054 Invalid topology of The geometry object cannot be used for creating a mapped

geometry 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 The current solution or the stored solution has for some

of DOFs in reason the wrong number of degrees of freedom, sometimes

initial value 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

An expression contains log(a), where a becomes negative

Attempt to

evaluate real or zero. To make the logarithm well-defined, make sure that

a>0. Often, a becomes only slightly negative (due to

logarithm of

negative number 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 When the equations have a structure such that the stiffness

on diagonal 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 The software ran out of memory during assembly of the finite

during assembly element model. See error 7144 regarding general

memory-saving tips.

6194

An expression contains a^b, where a becomes negative and

Attempt to

b is not an integer. To make the power well-defined, make

evaluate

sure that a>0. Often, a becomes only slightly negative (due

non-integral

power of to approximations in the solution process). Then, a possible

negative number

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

The model contains a sqrt (square root) function that takes

Attempt to

evaluate real the square root of a negative number. Either make sure that

square root of the square-root argument is nonnegative or select the

Use

negative number

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 Not-A-Number (NaN) appears unexpectedly. A possible

evaluation error: cause is improperly defined coupling variables. As a first step,

unexpected NaN check that the definitions of the source and destination

encountered domains of any coupling variables or periodic boundary

conditions are correct.

6245 Unsupported Integration order is too high. For triangular elements the order

integration 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

It is only possible to use adaptive mesh refinement in

3D for models using tetrahedral mesh elements.

tetrahedral meshes 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 The groups for the segregated solver do not include

do not involve all of all dependent variables. One reason for this error

solcomp 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 This error message usually appears when you have

undefined function value

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 The iterative linear system solver did not converge

linear iterations reached 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 You need to improve the quality of the preconditioner

preconditioner. The to get an accurate solution. For the Incomplete LU

relative residual is more preconditioner, lower the drop tolerance.

than 1000 times larger

than the relative

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 The name of a dependent variable in the

Manual

freedom name in manual

scaling edit field on the

Advanced page in the

scaling

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 encounters an undefined value (such values

appear, for instance, if a division by zero has been

performed or if some arithmetic operation results in a

larger number than can be represented by the

computer). For direct solvers this error might appear

if the stiffness matrix (Jacobian matrix) is singular or

almost singular. For iterative solvers this error might

appear, for instance, if the iterative process diverges.

Press the

Details button to see which linear solver

caused the error.

9000–9999 General Errors

TABLE 2-6: GENERAL ERROR MESSAGES

ERROR

NUMBER

ERROR MESSAGE EXPLANATION

9037 Failed to initialize

3D graphics.

OpenGL not fully

supported

OpenGL is not available on the computer. This can happen

if your graphics card does not support OpenGL or if you

have a Unix/Linux computer where OpenGL has not been

configured.

9040 Fatal error If you receive this error, click the

Detail button. Copy and

paste the entire error message and send it to

support@ along with your license file and

details of how to reproduce the error.

9052 Invalid

address/port

You did not enter the correct server name or server port

when trying to connect a client to a server.

9084 Server connection The client somehow lost the connection to the server. For

error example, the server crashed unexpectedly, or the power

saving mechanism on a laptop shut down the TCP/IP

connection.

9143 License error The most common reasons for this message:

The license file has been removed from the right

directory in the COMSOL software installation. The

file must be located in the

$COMSOL35a/license directory, where $COMSOL35a is

the COMSOL 3.5a installation directory.

The license manager has not started properly. Please find

the FLEXlm log file (named by the person who started the

license manager). Inspect this file to see the server status.

Send it to support@ if you are in doubt about

how to interpret this file.

It is crucial that you use the correct file on both

the server and the clients

9178 Error in callback An error occurred when calling a MATLAB function from

COMSOL Multiphysics. Make sure that the M-file that

defines the function is correct and exists in the current path.

Check that the function is written so that all inputs are

vectors of the same size and the output is a vector of the

same size.

Solver Error Messages

These error messages can appear during solution and appear on the Log tab in the Progress

window.

TABLE 2-7: SOLVER ERROR MESSAGES IN LOG WINDOW

SOLVER ERROR

MESSAGE

EXPLANATION

Cannot meet error The time-dependent solver cannot solve the model

tolerances. to the specified accuracy.

Increase absolute

or relative

tolerance.

Error in residual

computation

The evaluation of the residual or the Jacobian

generated an error during a time-dependent solution.

An additional message states the direct error. Some

Error in Jacobian

possible reasons are division by zero, range and

computation

overflow errors in mathematical functions, and

interpolation failure in coupling variables with

time-dependent mesh transformation.

Failed to find a

solution

The nonlinear solver failed to converge. An

additional error message gives some more details.

See the description for that message.

Failed to find a

solution for all

parameters, even

when using the

minimum

parameter step

During a parametric solution, the nonlinear iteration

did not converge despite reducing the parameter

step length to the minimum allowed value. The

solution may have reached a turning point or

bifurcation point.

Failed to find a The nonlinear solver failed to converge for the

solution for initial initial value of the parameter during a parametric

parameter solution. An additional error message gives some

more details. See the description for that message.

Failed to find

consistent initial

values

The time-dependent solver could not modify the

initial conditions given to a DAE system to satisfy

the stationary equations at the initial time. Make

sure the initial values satisfy the equations and

boundary conditions. In many cases, this can be

achieved by solving for only the algebraic variables

using a stationary solver before starting the

time-dependent solver.

Ill-conditioned

preconditioner.

Increase factor in

error estimate to X

The preconditioner is ill-conditioned. The error in

the solution might not be within tolerances. To be

sure to have a correct solution, open the

Linear

System Solver Settings dialog box from the

General tab of

Solver Parameters. Select

Linear

system solver in the tree, and increase

Factor in

error estimate to the suggested number X.

Alternatively, use a better preconditioner or tune the

settings for the preconditioner.

Inf or NaN found,

even when using

the minimum

damping factor

Despite reducing the step size to the minimum value

allowed, the solver cannot evaluate the residual or

modified Newton direction at the new solution

iterate. This essentially means that the current

approximation to the solution is close to the

boundary of the domain where the equations are

well-defined. Check the equations for divisions by

zero, powers, and other functions that can become

undefined for certain inputs.

Inverted mesh

element near

coordinates (x, y,

z)

In some mesh element near the given coordinates,

the (curved) mesh element is (partially) warped

inside-out. More precisely, the Jacobian matrix for

the mapping from local to global coordinates has a

negative determinant at some point. A possible

reason is that the linear mesh contains a tetrahedron

whose vertices all lie on a boundary. When

improving the approximation of the boundary using

curved mesh elements, the curved mesh element

becomes inverted. To see whether this is the case,

you can change

Geometry shape order to 1 in the

Model Settings dialog box, which means that

curved mesh elements will not be used. You can

usually avoid such bad tetrahedra by using a finer

mesh around the relevant boundary. Another reason

for this error message can be that the mesh becomes

inverted when using a deformed mesh.

Last time step is

not converged.

The last time step returned from the time-dependent

solver is not to be trusted. Earlier time steps are

within the specified tolerances.

Matrix is singular When encountered during time-dependent solution:

the linear system matrix (which is a linear

combination of the mass-, stiffness-, and possibly,

damping-matrices) is singular. Usually the problem

originates from the algebraic part of a DAE. In

particular, the cause can often be found in weak

constraints or constraint-like equations like the

continuity equation in incompressible flow.

Maximum number The iterative linear system solver failed to compute

of linear iterations a Newton direction in the specified maximum

reached number of iterations.

Maximum number The nonlinear solver could not reduce the error

of Newton below the desired tolerance in the specified

iterations reached maximum number of iterations. This is sometimes a

sign that the Jacobian is not complete or badly

scaled. It may even be almost singular, if the system

is underdetermined. If the returned solution seems

reasonable, it might be enough to restart the solver

with this solution as the initial guess.

No convergence,

even when using

the minimum

damping factor

The nonlinear solver reduced the damping factor

below the minimum value allowed. The solver

reduces the damping factor each time a computed

step did not lead to a decrease in the error estimate.

Make sure the model is well-posed, in particular that

there are enough equations and boundary conditions

to determine all degrees of freedom. If the model is

well-posed, it should have one or more isolated

solutions. In that case, the error is probably due to

the initial guess being too far from any solution.

Nonlinear solver

did not converge

During a time-dependent solution, the nonlinear

iteration failed to converge despite reducing the

time step to the minimum value allowed. Usually,

the error is related to the algebraic part of a DAE.

For example, the algebraic equations can have

reached a turning point or bifurcation point. The

error can also appear when the algebraic equations

do not have a unique solution consistent with the

given initial conditions. Make sure algebraic

equations have consistent initial values and that they

have a unique solution for all times and values

reached by the other variables.

Not all eigenvalues When the eigenvalue solver terminated (stopped by

returned the user or due to an error), it had not found the

requested number of eigenvalues. The eigenvalues

returned can be trusted.

Not all parameter After premature termination of the parametric

solver, only some of the requested solutions have

steps returned been computed.

Predicted solution The solver computes the initial guess for the new

guess leads to parameter value based on the solution for the

undefined function previous parameter value. This initial guess led to

value an undefined mathematical operation. Try using

another

Predictor on the

Parametric tab of

Solver Parameters.

Repeated error test During a time-dependent solution, the error

failures. May have tolerances could not be met despite reducing the

reached a time step to the minimum value allowed.

singularity.

Returned solution The solution returned by the stationary solver is not

has not converged. to be trusted. It might, however, be useful as initial

guess after modifying equations or solver settings.

The elasto-plastic The Newton iteration loop for the computation of

solver failed to the plastic state at some point in the geometry did

find a solution not converge.