各位老师好，我最近在尝试定义一个新的边界条件，结合timeVaryingMappedFixedValue和inletOutelt边界。在每个时间步对边界插值赋值之后，再根据边界上的通量判断入流/出流，将出流的区域设置zeroGradient，而入流区域仍采用插值结果。

下面是我参考inletOutlet边界文件修改的updateCoeffs()函数:

template<class Type>
void Foam::timeVaryingInletOutletFvPatchField<Type>::updateCoeffs()
{
    if (this->updated())
    {
        return;
    }
   
    this->operator==(fieldMapper_.map());
// 拷贝于‘inletOutlet’边界源文件，用于判断方向并对系数赋值
    const Field<scalar>& phip =
        this->patch().template lookupPatchField<surfaceScalarField, scalar>
        (
            phiName_
        );
    this->valueFraction() = 1.0 - pos0(phip);
//
    fixedValueFvPatchField<Type>::updateCoeffs();
}

新的边界条件能够成功编译。但在进行测试case（pimpleFoam）时，会在decomposePar分解并行区域步骤报错（直接进行单核计算也会出现相同错误）：

--> FOAM FATAL ERROR:
    request for surfaceScalarField phi from objectRegistry region0 failed
    available objects of type surfaceScalarField are 0()
    
    From function const Type& Foam::objectRegistry::lookupObject(const Foam::word&) const [with Type = Foam::GeometricField<double, Foam::fvsPatchField, Foam::surfaceMesh>] in file /home/gareth/OpenFOAM/OpenFOAM-8/src/OpenFOAM/lnInclude/objectRegistryTemplates.C at line 211.

以下是objectRegistryTemplates.C文件的对应内容：

        FatalErrorInFunction
            << nl
            << "    request for " << Type::typeName
            << " " << name << " from objectRegistry " << this->name()
            << " failed\n    available objects of type " << Type::typeName
            << " are" << nl
            << names<Type>();

        if (cacheTemporaryObject(name))
        {
            FatalErrorInFunction
                << nl
                << "    request for " << name << " from objectRegistry "
                << this->name() << " to be cached failed" << nl
                << "    available temporary objects are" << nl
                << temporaryObjects_;
        }
        FatalErrorInFunction                 // line 211
            << abort(FatalError);            // line 212
    }
    return NullObjectRef<Type>();

根据错误信息，似乎是没有找到surfaceScalarField类型的对象phi，但我只是结合inletOutlet边界，对原始的timeVaryingMappedFixedValue边界代码进行修改，并未改变其他源代码部分。并且我检查了求解器createFields.H，包含对通量phi的创建。所以我很困惑这个问题是如何产生的？

我是刚开始接触OpenFOAM的源代码，可能犯了一些愚蠢的错误。希望各位大佬能对该问题给出一些建议。谢谢！

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Gareth