Comsol heat sink, Hexagonal Fin Study

Work flow in the COMSOL Multiphysics

After completion of modelling the geometries of the heat sinks, a quantitative study is carried out; and it follows as:

Material describing Boundary conditions defining Meshing Solving and Post processing.

Material describing:

For both the heat sinks, the working conditions and material properties and domain properties are similar. And they are as follows:

Material parameters

Name Value Unit

Dynamic viscosity eta(T[1/K])[Pa*s] Pa*s

Ratio of specific heats 1.4 1

Heat capacity at constant pressure Cp(T[1/K])[J/(kg*K)] J/(kg*K)

Density rho(pA[1/Pa], T[1/K])[kg/m^3] kg/m^3

Thermal conductivity k(T[1/K])[W/(m*K)] W/(m*K)

Aluminium 3003-H18 (for Heat sinks)

Name Value Unit

Heat capacity at constant pressure 893[J/(kg*K)] J/(kg*K)

Density 2730[kg/m^3] kg/m^3

Thermal conductivity 155[W/(m*K)] W/(m*K)

Aluminium 3003-H18 heat sink (hexagonal fins)

Young’s modulus and Poisson’s ratio settings

Description Value

Young's modulus 69e9[Pa]

Poisson's ratio 0.33

Heat Transfer in Solids 1

Heat Transfer in Solids 1

SELECTION

Geometric entity level Domain

Selection Domains 2–11

Equations

PROPERTIES FROM MATERIAL

Property Material Property group

Thermal conductivity Aluminum 3003 - H18 Basic

Density Aluminum 3003 - H18 Basic

Heat capacity at constant pressure Aluminum 3003 - H18 Basic

Boundary Conditions Defining

Thermal Insulation 1


SELECTION

Geometric entity level Boundary

Selection Boundaries 2–5, 8

Equations

Wall 1

Wall 1

SELECTION

Geometric entity level

Boundary

SelectionBoundaries 2–7, 9–12, 14–16, 18–20, 22–36, 38–40, 42–44, 46–60, 62–64, 66–68, 70–83

Equations

Initial Values 1

Initial Values 1

SELECTION


Domain


Fluid 1

Fluid 1

SELECTION


Selection Domain 1

Equations

PROPERTIES FROM MATERIAL

Property Material Property group

Density Air Basic

Dynamic viscosity Air Basic

Thermal conductivity Air Basic

Heat capacity at constant pressure Air Basic

Ratio of specific heats Air Basic

Heat Source 1

Heat Source 1

SELECTION


Selection Domain 2

Equations

SETTINGS

Description Value

Heat source Total power

Total power 1

Inlet 1

Inlet 1

SELECTION


Selection Boundary 84

Equations

SETTINGS

Description Value

Boundary condition Laminar inflow

Average velocity 5[cm/s]

Outlet 1

Outlet 1

SELECTION


Boundary


Equations

Temperature 1

Temperature 1

SELECTION



Equations

SETTINGS

Description Value

Temperature 20[degC]

Outflow 1

Outflow 1

SELECTION


Boundary


Equations

MESH 1

Mesh 1

Size (Size)

SETTINGS

Name Value

Maximum element size 0.0080

Minimum element size 0.00144

Resolution of curvature 0.6

Resolution of narrow regions 0.5

Maximum element growth rate 1.5

SOLVER CONFIGURATIONS

Compile Equations: Stationary (St1)

STUDY AND STEP

Name Value

Use study Study 1

Use study step Stationary

Dependent Variables 1 (V1)

GENERAL

Name Value

Defined by study step

Stationary

INITIAL VALUES OF VARIABLES SOLVED FOR

Name Value

Solution Zero

VALUES OF VARIABLES NOT SOLVED FOR

Name Value

Solution Zero

Mod1.u (Mod1_u)

GENERAL

Name Value

Field components {mod1.u, mod1.v, mod1.w}

Mod1.T (Mod1_T)

GENERAL

Name Value

Field components mod1.T

Mod1.p (Mod1_p)

GENERAL

Name Value

Field components mod1.p

Mod1.nitf.Pinlinl1 (Mod1_nitf_Pinlinl1)

GENERAL

Name Value

State components

mod1.nitf.Pinlinl1

Stationary Solver 1 (S1)

GENERAL

Name Value

Defined by study step

Stationary

Fully Coupled 1 (Fc1)

GENERAL

Name Value

Linear solver

Iterative 1

METHOD AND TERMINATION

Name Value

Nonlinear method

Constant (Newton)

Damping factor 0.8

Iterative 1 (I1)

ERROR

Name Value

Factor in error estimate 20

Maximum number of iterations 200

Nonlinear based error norm On

Multigrid 1 (Mg1)

Presmoother (Pr)

Vanka 1 (Va1)

MAIN

Name Value

Number of iterations 1

Variables mod1.nitf.Pinlinl1

SECONDARY

Name Value

Relaxation factor

0.6

Postsmoother (Po)

Vanka 1 (Va1)

MAIN

Name Value

Number of iterations 1

Variables mod1.nitf.Pinlinl1

SECONDARY

Name Value

Number of secondary iterations

2

Relaxation factor 0.7

Coarse Solver (Cs)

Direct 1 (D1)

GENERAL

Name Value

Solver PARDISO

Results

DATA SETS

Solution 1

SELECTION


Domain

Selection Geometry geom1

SOLUTION

Name Value

Solution Solver 1

Model Save Point Geometry 1

Surface 1

SELECTION


Boundary

SelectionBoundaries 2–7, 9–12, 14–16, 18–20, 22–36, 38–40, 42–44, 46–60, 62–64, 66–68, 70–83

SQUARE FIN ANALYSIS

Definitions

Coordinate Systems

Boundary System 1

Coordinate system type Boundary system

Identifier sys1

Geometry 1

Geometry 1

unitsLength unit m

Angular unit Deg

Materials

Air

Air

SelectionGeometric entity level Domain

Selection Domain 1

Aluminum 3003-H18

Aluminum 3003-H18



Conjugate Heat Transfer (nitf)

Conjugate Heat Transfer

FeaturesHeat Transfer in Solids 1


Wall 1

Initial Values 1

Fluid 1

Heat Source 1

Inlet 1

Temperature 1

Outlet 1

Outflow 1

Mesh 1

Mesh 1

STUDY

Stationary

Mesh selectionGeometry Mesh

Geometry 1 (geom1)

mesh1

Physics selectionPhysics Discretization

Conjugate Heat Transfer (nitf)

physics

RESULTS

Data Sets

Solution 1


Selection Geometry geom1

SolutionName Value

Solution Solver 1

Name Value

Model Save Point Geometry 1

Surface 1

SelectionGeometric entity level Boundary

Selection Boundaries 2–7, 9–12, 14–17, 19–22, 24–30, 32–35, 37–40, 42–48, 50–53, 55–58, 60–65

DataName Value

Data set Solution 1

Documents

Comsol heat sink, Hexagonal Fin Study