各位好，
试了一下以下代码：

	fvVectorMatrix DEqn1
        (
            fvm::laplacian(impKf_, D(), "laplacian(DD,D)")
            - fvc::laplacian(impKf_, D(), "laplacian(DD,D)")
	);

        fvVectorMatrix DEqn2
       (
          fvm::laplacian(impKf_, D(), "laplacian(DD,D)")
          - fvc::laplacian(impKf_, D(), "laplacian(DD,D)")
       );

Info << "source of DEqn1: " << DEqn1.source() << endl;
Info << "source of DEqn2: " << DEqn2.source() << endl;

输出的结果为：

source of DEqn1: 4{(0 0 0)}
source of DEqn2: 4((0 0 0) (0 0 0) (0 0 0) (0 -27000 0))

为什么这两个fvMatrix的源项会有不同？初始化的参数都是相同的。

BTW，fvc::laplacian(impKf_, D(), "laplacian(DD,D)")的值为：

dimensions      [1 -2 -2 0 0 0 0];

internalField   nonuniform List<vector> 4((0 0 0) (0 0 0) (0 0 0) (0 -180000 0));

boundaryField
{
    top
    {
        type            zeroGradient;
    }
    left
    {
        type            zeroGradient;
    }
    right
    {
        type            zeroGradient;
    }
    bottom
    {
        type            zeroGradient;
    }
    front
    {
        type            empty;
    }
    back
    {
        type            empty;
    }
}

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