OpenLB 1.7
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olb::HertzMindlinDeresiewicz3D< T, PARTICLETYPE, DESCRIPTOR > Class Template Reference

#include <hertzMindlinDeresiewicz3D.h>

+ Inheritance diagram for olb::HertzMindlinDeresiewicz3D< T, PARTICLETYPE, DESCRIPTOR >:
+ Collaboration diagram for olb::HertzMindlinDeresiewicz3D< T, PARTICLETYPE, DESCRIPTOR >:

Public Member Functions

 HertzMindlinDeresiewicz3D (T G1, T G2, T v1, T v2, T scale1=T(1.), T scale2=T(1.), bool validationKruggelEmden=false)
 
 ~HertzMindlinDeresiewicz3D () override
 
void applyForce (typename std::deque< PARTICLETYPE< T > >::iterator p, int pInt, ParticleSystem3D< T, PARTICLETYPE > &pSys) override
 
void computeForce (typename std::deque< PARTICLETYPE< T > >::iterator p, int pInt, ParticleSystem3D< T, PARTICLETYPE > &pSys, T force[3])
 
 HertzMindlinDeresiewicz3D (T G1, T G2, T v1, T v2, T scale1=T(1.), T scale2=T(1.), bool validationKruggelEmden=false)
 
 ~HertzMindlinDeresiewicz3D () override
 
void applyForce (typename std::deque< PARTICLETYPE< T > >::iterator p, int pInt, ParticleSystem3D< T, PARTICLETYPE > &pSys) override
 
void computeForce (typename std::deque< PARTICLETYPE< T > >::iterator p, int pInt, ParticleSystem3D< T, PARTICLETYPE > &pSys, T force[3])
 
- Public Member Functions inherited from olb::Force3D< T, PARTICLETYPE >
 Force3D ()
 
 Force3D (Force3D< T, PARTICLETYPE > &)
 
 Force3D (const Force3D< T, PARTICLETYPE > &)
 
virtual ~Force3D ()
 

Additional Inherited Members

- Protected Attributes inherited from olb::Force3D< T, PARTICLETYPE >
OstreamManager clout
 

Detailed Description

template<typename T, template< typename U > class PARTICLETYPE, typename DESCRIPTOR>
class olb::HertzMindlinDeresiewicz3D< T, PARTICLETYPE, DESCRIPTOR >

Definition at line 47 of file hertzMindlinDeresiewicz3D.h.

Constructor & Destructor Documentation

◆ HertzMindlinDeresiewicz3D() [1/2]

template<typename T , template< typename U > class PARTICLETYPE, typename DESCRIPTOR >
olb::HertzMindlinDeresiewicz3D< T, PARTICLETYPE, DESCRIPTOR >::HertzMindlinDeresiewicz3D ( T G1,
T G2,
T v1,
T v2,
T scale1 = T(1.),
T scale2 = T(1.),
bool validationKruggelEmden = false )

Definition at line 38 of file hertzMindlinDeresiewicz3D.hh.

39 :
40 Force3D<T, PARTICLETYPE>(), _G1(G1), _G2(G2), _v1(v1), _v2(v2), _scale1(
41 scale1), _scale2(scale2), _validationKruggelEmden(validationKruggelEmden)
42{
43 // E-Modul Particle
44 E1 = 2 * (1 + _v1) * _G1;
45 E2 = 2 * (1 + _v2) * _G2;
46
47 // equivalent combined E-Modul
48 eE = (1 - util::pow(_v1, 2)) / E1 + (1 - util::pow(_v2, 2)) / E2;
49 eE = 1 / eE;
50
51 // equivalent combined E-Modul
52 eG = (2.0 - _v1) / _G1 + (2 - _v2) / _G2;
53 eG = 1. / eG;
54}
olb::util::pow
cpu::simd::Pack< T > pow(cpu::simd::Pack< T > base, cpu::simd::Pack< T > exp)
Definition pack.h:112

References olb::util::pow().

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◆ ~HertzMindlinDeresiewicz3D() [1/2]

template<typename T , template< typename U > class PARTICLETYPE, typename DESCRIPTOR >
olb::HertzMindlinDeresiewicz3D< T, PARTICLETYPE, DESCRIPTOR >::~HertzMindlinDeresiewicz3D ( )
inlineoverride

Definition at line 52 of file hertzMindlinDeresiewicz3D.h.

52{};

◆ HertzMindlinDeresiewicz3D() [2/2]

template<typename T , template< typename U > class PARTICLETYPE, typename DESCRIPTOR >
olb::HertzMindlinDeresiewicz3D< T, PARTICLETYPE, DESCRIPTOR >::HertzMindlinDeresiewicz3D ( T G1,
T G2,
T v1,
T v2,
T scale1 = T(1.),
T scale2 = T(1.),
bool validationKruggelEmden = false )

◆ ~HertzMindlinDeresiewicz3D() [2/2]

template<typename T , template< typename U > class PARTICLETYPE, typename DESCRIPTOR >
olb::HertzMindlinDeresiewicz3D< T, PARTICLETYPE, DESCRIPTOR >::~HertzMindlinDeresiewicz3D ( )
inlineoverride

Definition at line 54 of file hertzMindlinDeresiewiczForCombWithCollisionModel3D.h.

54{};

Member Function Documentation

◆ applyForce() [1/2]

template<typename T , template< typename U > class PARTICLETYPE, typename DESCRIPTOR >
void olb::HertzMindlinDeresiewicz3D< T, PARTICLETYPE, DESCRIPTOR >::applyForce ( typename std::deque< PARTICLETYPE< T > >::iterator p,
int pInt,
ParticleSystem3D< T, PARTICLETYPE > & pSys )
overridevirtual

Implements olb::Force3D< T, PARTICLETYPE >.

Definition at line 57 of file hertzMindlinDeresiewicz3D.hh.

60{
61 T force[3] = {T(), T(), T()};
62
63 computeForce(p, pInt, pSys, force);
64}
olb::HertzMindlinDeresiewicz3D::computeForce
void computeForce(typename std::deque< PARTICLETYPE< T > >::iterator p, int pInt, ParticleSystem3D< T, PARTICLETYPE > &pSys, T force[3])
Definition hertzMindlinDeresiewicz3D.hh:67

◆ applyForce() [2/2]

template<typename T , template< typename U > class PARTICLETYPE, typename DESCRIPTOR >
void olb::HertzMindlinDeresiewicz3D< T, PARTICLETYPE, DESCRIPTOR >::applyForce ( typename std::deque< PARTICLETYPE< T > >::iterator p,
int pInt,
ParticleSystem3D< T, PARTICLETYPE > & pSys )
overridevirtual

Implements olb::Force3D< T, PARTICLETYPE >.

◆ computeForce() [1/2]

template<typename T , template< typename U > class PARTICLETYPE, typename DESCRIPTOR >
void olb::HertzMindlinDeresiewicz3D< T, PARTICLETYPE, DESCRIPTOR >::computeForce ( typename std::deque< PARTICLETYPE< T > >::iterator p,
int pInt,
ParticleSystem3D< T, PARTICLETYPE > & pSys,
T force[3] )

Definition at line 67 of file hertzMindlinDeresiewicz3D.hh.

70{
71
72 std::vector<std::pair<size_t, T>> ret_matches;
73 // kind of contactDetection has to be chosen in application
74 pSys.getContactDetection()->getMatches(pInt, ret_matches);
75
76 PARTICLETYPE<T>* p2 = NULL;
77
78 // iterator walks through number of neighbored particles = ret_matches
79 for (const auto& it : ret_matches) {
80
81 if (!util::nearZero(it.second)) {
82
83 p2 = &pSys[it.first];
84
85 // overlap
86 T delta = (p2->getRad() + p->getRad()) - util::sqrt(it.second);
87
88 // equivalent mass
89 T M = p->getMass() * p2->getMass() / (p->getMass() + p2->getMass());
90 // equivalent radius
91 T R = p->getRad() * p2->getRad() / (p->getRad() + p2->getRad());
92 // relative velocity
93 std::vector < T > _velR(3, T());
94 _velR[0] = -(p2->getVel()[0] - p->getVel()[0]);
95 _velR[1] = -(p2->getVel()[1] - p->getVel()[1]);
96 _velR[2] = -(p2->getVel()[2] - p->getVel()[2]);
97
98 std::vector < T > _d(3, T());
99 std::vector < T > _normal(3, T());
100
101 //_d: vector from particle1 to particle2
102 _d[0] = p2->getPos()[0] - p->getPos()[0];
103 _d[1] = p2->getPos()[1] - p->getPos()[1];
104 _d[2] = p2->getPos()[2] - p->getPos()[2];
105
106 if ( !util::nearZero(util::norm(_d)) ) {
107 _normal = util::normalize(_d);
108 }
109 else {
110 return;
111 }
112
113 Vector<T, 3> d_(_d);
114 Vector<T, 3> velR_(_velR);
115 T dot = velR_[0] * _normal[0] + velR_[1] * _normal[1] + velR_[2] * _normal[2];
116
117 // normal part of relative velocity
118 // normal relative to surface of particles at contact point
119 std::vector < T > _velN(3, T());
120 _velN[0] = dot * _normal[0];
121 _velN[1] = dot * _normal[1];
122 _velN[2] = dot * _normal[2];
123
124 // tangential part of relative velocity
125 // tangential relative to surface of particles at contact point
126 std::vector < T > _velT(3, T());
127 _velT[0] = _velR[0] - _velN[0];
128 _velT[1] = _velR[1] - _velN[1];
129 _velT[2] = _velR[2] - _velN[2];
130
131 if (delta > 0.) {
132
133 // Force normal
134 // spring constant in normal direction
135 // (Alberto Di Renzo, Francesco Paolo Di Maio, Chemical Engineering Science 59 (2004) 525 - 541)
136 // constant kn from H. Kruggel-Endem
137 T kn = 4 / 3. * util::sqrt(R) * eE;
138 if (_validationKruggelEmden) {
139 kn = 7.35e9; // to compare to Kruggel-Emden
140 }
141
142 // part of mechanical force of spring in normal direction
143 // Hertz Contact (P. A. Langston, Powder Technology 85 (1995))
144 std::vector < T > Fs_n(3, T());
145 Fs_n[0] = -kn * util::pow(delta, 1.5) * _normal[0];
146 Fs_n[1] = -kn * util::pow(delta, 1.5) * _normal[1];
147 Fs_n[2] = -kn * util::pow(delta, 1.5) * _normal[2];
148
149 // part of mechanical force of damper in normal direction
150 // damped linear spring (Cundall, Strack 1979)
151 // (K.W. Chu, A.B. Yu, Powder Technology 179 (2008) 104 – 114)
152 // damper constant in normal direction
153 // constant eta_n from H. Kruggel-Endem
154 T eta_n = 0.3 * util::sqrt(4.5 * M * util::sqrt(delta) * kn);
155 if (_validationKruggelEmden) {
156 eta_n = 1.96e5; // to compare to Kruggel-Emden
157 }
158
159 std::vector < T > Fd_n(3, T());
160 Fd_n[0] = -eta_n * _velN[0] * util::sqrt(delta);
161 Fd_n[1] = -eta_n * _velN[1] * util::sqrt(delta);
162 Fd_n[2] = -eta_n * _velN[2] * util::sqrt(delta);
163
164 std::vector < T > F_n(3, T());
165 F_n[0] = Fs_n[0] + Fd_n[0];
166 F_n[1] = Fs_n[1] + Fd_n[1];
167 F_n[2] = Fs_n[2] + Fd_n[2];
168
169 // Force tangential
170 // spring constant in tangential direction
171 // (N.G. Deen, Chemical Engineering Science 62 (2007) 28 - 44)
172 T kt = 2 * util::sqrt(2 * R) * _G1 / (2 - _v1) * util::pow(delta, 0.5);
173
174 // damper constant in normal direction
175 T eta_t = 2 * util::sqrt(2. / 7. * M * kt);
176
177 // part of mechanical force of damper in tangential direction
178 std::vector < T > F_t(3, T());
179 F_t[0] = -eta_t * _velT[0];
180 F_t[1] = -eta_t * _velT[1];
181 F_t[2] = -eta_t * _velT[2];
182
183 // entire force
184 // factor _scale to prevent instability
185 force[0] = _scale1 * F_n[0] + _scale2 * F_t[0];
186 force[1] = _scale1 * F_n[1] + _scale2 * F_t[1];
187 force[2] = _scale1 * F_n[2] + _scale2 * F_t[2];
188
189 p->getForce()[0] += force[0] * 0.5 ;
190 p->getForce()[1] += force[1] * 0.5 ;
191 p->getForce()[2] += force[2] * 0.5 ;
192 p2->getForce()[0] -= force[0] * 0.5 ;
193 p2->getForce()[1] -= force[1] * 0.5 ;
194 p2->getForce()[2] -= force[2] * 0.5 ;
195 }
196 }
197 }
198}
olb::descriptors::mrt_data::M
platform_constant Fraction M[Q][Q]
Definition mrtLatticeDescriptors.h:65
olb::util::sqrt
cpu::simd::Pack< T > sqrt(cpu::simd::Pack< T > value)
Definition pack.h:100
olb::util::norm
T norm(const std::vector< T > &a)
l2 norm of a vector of arbitrary length
Definition vectorHelpers.h:146
olb::util::normalize
Vector< T, D > normalize(const Vector< T, D > &a)
Definition vectorHelpers.h:193
olb::util::nearZero
bool nearZero(const ADf< T, DIM > &a)
Definition aDiff.h:1087

References olb::ParticleSystem3D< T, PARTICLETYPE >::getContactDetection(), olb::util::nearZero(), olb::util::norm(), olb::util::normalize(), olb::util::pow(), and olb::util::sqrt().

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◆ computeForce() [2/2]

template<typename T , template< typename U > class PARTICLETYPE, typename DESCRIPTOR >
void olb::HertzMindlinDeresiewicz3D< T, PARTICLETYPE, DESCRIPTOR >::computeForce ( typename std::deque< PARTICLETYPE< T > >::iterator p,
int pInt,
ParticleSystem3D< T, PARTICLETYPE > & pSys,
T force[3] )
The documentation for this class was generated from the following files:
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