Particle-drag model wherein drag forces (per unit carrier-fluid velocity) are dynamically computed based on empirical expressions using a four-parameter general drag correlation for non-spherical particles. More...

Inheritance diagram for NonSphereDragForce< CloudType >:

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Collaboration diagram for NonSphereDragForce< CloudType >:

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Public Member Functions
	TypeName ("nonSphereDrag")
	Runtime type information. More...

	NonSphereDragForce (CloudType &owner, const fvMesh &mesh, const dictionary &dict)
	Construct from mesh. More...

	NonSphereDragForce (const NonSphereDragForce< CloudType > &df)
	Construct copy. More...

virtual autoPtr< ParticleForce< CloudType > >	clone () const
	Construct and return a clone. More...

void	operator= (const NonSphereDragForce< CloudType > &)=delete
	No copy assignment. More...

virtual	~NonSphereDragForce ()=default
	Destructor. More...

virtual forceSuSp	calcCoupled (const typename CloudType::parcelType &p, const typename CloudType::parcelType::trackingData &td, const scalar dt, const scalar mass, const scalar Re, const scalar muc) const
	Calculate the non-coupled force. More...

Public Member Functions inherited from ParticleForce< CloudType >
	TypeName ("particleForce")
	Runtime type information. More...

	declareRunTimeSelectionTable (autoPtr, ParticleForce, dictionary,(CloudType &owner, const fvMesh &mesh, const dictionary &dict),(owner, mesh, dict))
	Declare runtime constructor selection table. More...

	ParticleForce (CloudType &owner, const fvMesh &mesh, const dictionary &dict, const word &forceType, const bool readCoeffs)
	Construct from mesh. More...

	ParticleForce (const ParticleForce &pf)
	Construct copy. More...

virtual autoPtr< ParticleForce< CloudType > >	clone () const
	Construct and return a clone. More...

virtual	~ParticleForce ()
	Destructor. More...

const CloudType &	owner () const
	Return const access to the cloud owner. More...

CloudType &	owner ()
	Return reference to the cloud owner. More...

const fvMesh &	mesh () const
	Return the mesh database. More...

const dictionary &	coeffs () const
	Return the force coefficients dictionary. More...

virtual void	cacheFields (const bool store)
	Cache fields. More...

virtual forceSuSp	calcCoupled (const typename CloudType::parcelType &p, const typename CloudType::parcelType::trackingData &td, const scalar dt, const scalar mass, const scalar Re, const scalar muc) const
	Calculate the coupled force. More...

virtual forceSuSp	calcNonCoupled (const typename CloudType::parcelType &p, const typename CloudType::parcelType::trackingData &td, const scalar dt, const scalar mass, const scalar Re, const scalar muc) const
	Calculate the non-coupled force. More...

virtual scalar	massAdd (const typename CloudType::parcelType &p, const typename CloudType::parcelType::trackingData &td, const scalar mass) const
	Return the added mass. More...

Protected Member Functions
scalar	CdRe (const scalar Re) const
	Drag coefficient multiplied by Reynolds number. More...

Protected Attributes
scalar	phi_

scalar	a_

scalar	b_

scalar	c_

scalar	d_

Additional Inherited Members
Public Types inherited from ParticleForce< CloudType >
typedef VectorSpace< Vector< vector >, vector, 2 >	returnType
	Convenience typedef for return type. More...

Static Public Member Functions inherited from ParticleForce< CloudType >
static autoPtr< ParticleForce< CloudType > >	New (CloudType &owner, const fvMesh &mesh, const dictionary &dict, const word &forceType)
	Selector. More...

Detailed Description

template<class CloudType>
class Foam::NonSphereDragForce< CloudType >

Particle-drag model wherein drag forces (per unit carrier-fluid velocity) are dynamically computed based on empirical expressions using a four-parameter general drag correlation for non-spherical particles.

\[ \mathrm{F}_\mathrm{D} = \frac{3}{4} \frac{\mu_c\,\mathrm{C}_\mathrm{D}\,\mathrm{Re}_p}{\rho_p \, d_p^2} \]

with

\[ \mathrm{C}_\mathrm{D} = \frac{24}{\mathrm{Re}_p} \left( 1 + A \, \mathrm{Re}_p^B \right) + \frac{C \, \mathrm{Re}_p}{D + \mathrm{Re}_p} \]

where

\[ A = \exp(2.3288 - 6.4581\phi + 2.4486 \phi^2) \]

\[ B = 0.0964 + 0.5565\phi \]

\[ C = \exp(4.9050 - 13.8944\phi + 18.4222\phi^2 - 10.2599 \phi^3) \]

\[ D = \exp(1.4681 + 12.2584\phi - 20.7322\phi^2 + 15.8855\phi^3) \]

\[ \phi = \frac{A_p}{A_a} \]

\[ \mathrm{Re}_p = \frac{\rho_c \, | \mathbf{u}_\mathrm{rel} | \, d_p}{\mu_c} \]

where

\( \mathrm{F}_\mathrm{D} \)	=	Drag force per carrier-fluid velocity [kg/s]
\( \mathrm{C}_\mathrm{D} \)	=	Particle drag coefficient
\( \mathrm{Re}_p \)	=	Particle Reynolds number
\( \rho_p \)	=	Particle mass density
\( \mu_c \)	=	Dynamic viscosity of carrier at the cell occupying particle
\( d_p \)	=	Particle diameter
\( \rho_c \)	=	Density of carrier at the cell occupying particle
\( \mathbf{u}_\mathrm{rel} \)	=	Relative velocity between particle and carrier
\( A_p \)	=	Surface area of sphere with the same volume as the particle
\( A_a \)	=	Actual surface area of the particle
\( \phi \)	=	Ratio of surface areas

Constraints:

Applicable to particles with a spatially homogeneous distribution.
\( 1 \geq \phi > 0 \)

References:

        Standard model (tag:HL), (Eq. 4,10-11):
            Haider, A., & Levenspiel, O. (1989).
            Drag coefficient and terminal velocity of
            spherical and nonspherical particles.
            Powder technology, 58(1), 63-70.
            DOI:10.1016/0032-5910(89)80008-7

Usage

Minimal example by using constant/<CloudProperties>:

subModels
{
    particleForces
    {
        nonSphereDrag
        {
            phi    <phi>;
        }
    }
}

where the entries mean:

Property Description Type Reqd Deflt

type Type name: nonSphereDrag word yes -

phi

Ratio of surface area of sphere having same

volume as particle to actual surface area of

particle

scalar

yes

-

Note

The drag coefficient model in (HL:Eq. 11) is good to within 2 to 4 % of RMS values from the corresponding experiment.
(HL:Eq. 12) also give a simplified model with greater error compared to results from the experiment, but since phi is presumed constant, Eq. 12 offers little benefit.
\(\mathrm{F}_\mathrm{D}\) is weighted with the particle mass at the stage of a function return, so that it can later be normalised with the effective mass, if necessary (e.g. when using virtual-mass forces).

Source files

Definition at line 224 of file NonSphereDragForce.H.

Constructor & Destructor Documentation

◆ NonSphereDragForce() [1/2]

NonSphereDragForce	(	CloudType &	owner,
		const fvMesh &	mesh,
		const dictionary &	dict
	)

Construct from mesh.

Definition at line 44 of file NonSphereDragForce.C.

References Foam::exit(), Foam::exp(), Foam::FatalError, FatalErrorInFunction, Foam::pow3(), and Foam::sqr().

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◆ NonSphereDragForce() [2/2]

NonSphereDragForce ( const NonSphereDragForce< CloudType > & df )

Construct copy.

Definition at line 69 of file NonSphereDragForce.C.

◆ ~NonSphereDragForce()

virtual ~NonSphereDragForce ( )

virtualdefault

Destructor.

Member Function Documentation

◆ CdRe()

Foam::scalar CdRe ( const scalar Re ) const

protected

Drag coefficient multiplied by Reynolds number.

Definition at line 34 of file NonSphereDragForce.C.

References Foam::pow(), and Foam::Re().

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◆ TypeName()

TypeName ( "nonSphereDrag" )

Runtime type information.

◆ clone()

virtual autoPtr< ParticleForce< CloudType > > clone ( ) const

inlinevirtual

Construct and return a clone.

Reimplemented from ParticleForce< CloudType >.

Definition at line 274 of file NonSphereDragForce.H.

◆ operator=()

void operator= ( const NonSphereDragForce< CloudType > & )

delete

No copy assignment.

◆ calcCoupled()

Foam::forceSuSp calcCoupled	(	const typename CloudType::parcelType &	p,
		const typename CloudType::parcelType::trackingData &	td,
		const scalar	dt,
		const scalar	mass,
		const scalar	Re,
		const scalar	muc
	)		const

virtual

Calculate the non-coupled force.

Reimplemented from ParticleForce< CloudType >.

Definition at line 86 of file NonSphereDragForce.C.

References p, Foam::Re(), Foam::sqr(), and Foam::Zero.

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Member Data Documentation

◆ phi_

scalar phi_

protected

Ratio of surface of sphere having same volume as particle to actual surface area of particle (0 < phi <= 1)

Definition at line 234 of file NonSphereDragForce.H.

◆ a_

scalar a_

protected

Definition at line 239 of file NonSphereDragForce.H.

◆ b_

scalar b_

protected

Definition at line 241 of file NonSphereDragForce.H.

◆ c_

scalar c_

protected

Definition at line 243 of file NonSphereDragForce.H.

◆ d_

scalar d_

protected

Definition at line 245 of file NonSphereDragForce.H.

The documentation for this class was generated from the following files:

src/lagrangian/intermediate/submodels/Kinematic/ParticleForces/Drag/NonSphereDrag/NonSphereDragForce.H
src/lagrangian/intermediate/submodels/Kinematic/ParticleForces/Drag/NonSphereDrag/NonSphereDragForce.C

Public Member Functions

Protected Member Functions

Protected Attributes

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ NonSphereDragForce() [1/2]

◆ NonSphereDragForce() [2/2]

◆ ~NonSphereDragForce()

Member Function Documentation

◆ CdRe()

◆ TypeName()

◆ clone()

◆ operator=()

◆ calcCoupled()

Member Data Documentation

◆ phi_

◆ a_

◆ b_

◆ c_

◆ d_