# Package Modelica.​Fluid.​Dissipation.​Utilities.​SharedDocumentation.​HeatTransfer.​PlateIcon for general information packages

### Information

This icon indicates classes containing only documentation, intended for general description of, e.g., concepts and features of a package.

Extends from `Modelica.​Icons.​Information` (Icon for general information packages).

### Package Contents

NameDescription
`kc_laminar`
`kc_overall`
`kc_turbulent`

## Class Modelica.​Fluid.​Dissipation.​Utilities.​SharedDocumentation.​HeatTransfer.​Plate.​kc_laminarIcon for general information packages

### Information

Calculation of the mean convective heat transfer coefficient kc for a laminar fluid flow over an even surface.

#### Functions kc_laminar and kc_laminar_KC

There are basically three differences:

• The function kc_laminar is using kc_laminar_KC but offers additional output variables like e.g. Reynolds number or Nusselt number and failure status (an output of 1 means that the function is not valid for the inputs).
• Generally the function kc_laminar_KC is numerically best used for the calculation of the mean convective heat transfer coefficient kc at known mass flow rate.
• You can perform an inverse calculation from kc_laminar_KC, where an unknown mass flow rate is calculated out of a given mean convective heat transfer coefficient kc

#### Restriction

• laminar regime (Reynolds number ≤ 1e5)
• Prandtl number 0.6 ≤ Pr ≤ 2000

#### Calculation

The mean convective heat transfer coefficient kc for flat plate is calculated through the corresponding Nusselt number Nu_lam according to [VDI 2002, p. Gd 1, eq. 1] :

```    Nu_lam = 0.664 * Re^(0.5) * (Pr)^(1/3)
```

and the corresponding mean convective heat transfer coefficient kc :

```    kc =  Nu_lam * lambda / L
```

with

 cp as specific heat capacity at constant pressure [J/(kg.K)], eta as dynamic viscosity of fluid [Pa.s], kc as mean convective heat transfer coefficient [W/(m2.K)], lambda as heat conductivity of fluid [W/(m.K)], L as length of plate [m], Nu_lam as mean Nusselt number for laminar regime [-], Pr = eta*cp/lambda as Prandtl number [-], rho as fluid density [kg/m3], Re = rho*v*L/eta as Reynolds number [-].

#### Verification

The mean Nusselt number Nu in the laminar regime representing the mean convective heat transfer coefficient kc for Prandtl numbers of different fluids is shown in the figure below.

Note that this function is best used in the laminar regime up to a Reynolds number Re smaller than 2300. There is a deviation w.r.t. literature due to the neglect of the turbulence influence in the transition regime even though this function is used inside its cited restrictions for a higher Reynolds number. The function kc_overall is recommended for the simulation of a Reynolds number higher than 2300.

#### References

VDI:
VDI - Wärmeatlas: Berechnungsblätter für den Wärmeübergang. Springer Verlag, 9th edition, 2002.

Extends from `Modelica.​Icons.​Information` (Icon for general information packages).

## Class Modelica.​Fluid.​Dissipation.​Utilities.​SharedDocumentation.​HeatTransfer.​Plate.​kc_overallIcon for general information packages

### Information

Calculation of the mean convective heat transfer coefficient kc for a laminar or turbulent fluid flow over an even surface.

#### Functions kc_overall and kc_overall_KC

There are basically three differences:

• The function kc_overall is using kc_overall_KC but offers additional output variables like e.g. Reynolds number or Nusselt number and failure status (an output of 1 means that the function is not valid for the inputs).
• Generally the function kc_overall_KC is numerically best used for the calculation of the mean convective heat transfer coefficient kc at known mass flow rate.
• You can perform an inverse calculation from kc_overall_KC, where an unknown mass flow rate is calculated out of a given mean convective heat transfer coefficient kc

#### Restriction

• constant wall temperature
• overall regime (Reynolds number 1e1 < Re < 1e7)
• Prandtl number 0.6 ≤ Pr ≤ 2000

#### Geometry and Calculation

This heat transfer function enables a calculation of heat transfer coefficient for laminar and turbulent flow regime. The geometry, constant and fluid parameters of the function are the same as for kc_laminar and kc_turbulent.

The calculation conditions for laminar and turbulent flow is equal to the calculation in kc_laminar and kc_turbulent. A smooth transition between both functions is carried out between 1e5 ≤ Re ≤ 5e5 (see figure below).

#### Verification

The mean Nusselt number Nu = sqrt(Nu_lam^2 + Nu_turb^2) representing the mean convective heat transfer coefficient kc for Prandtl numbers of different fluids is shown in the figure below.

#### References

VDI:
VDI - Wärmeatlas: Berechnungsblätter für den Wärmeübergang. Springer Verlag, 9th edition, 2002.

Extends from `Modelica.​Icons.​Information` (Icon for general information packages).

## Class Modelica.​Fluid.​Dissipation.​Utilities.​SharedDocumentation.​HeatTransfer.​Plate.​kc_turbulentIcon for general information packages

### Information

Calculation of the mean convective heat transfer coefficient kc for a hydrodynamically developed turbulent fluid flow over an even surface.

#### Functions kc_turbulent and kc_turbulent_KC

There are basically three differences:

• The function kc_turbulent is using kc_turbulent_KC but offers additional output variables like e.g. Reynolds number or Nusselt number and failure status (an output of 1 means that the function is not valid for the inputs).
• Generally the function kc_turbulent_KC is numerically best used for the calculation of the mean convective heat transfer coefficient kc at known mass flow rate.
• You can perform an inverse calculation from kc_turbulent_KC, where an unknown mass flow rate is calculated out of a given mean convective heat transfer coefficient kc

#### Restriction

• constant wall temperature
• turbulent regime (Reynolds number 5e5 < Re < 1e7)
• Prandtl number 0.6 ≤ Pr ≤ 2000

#### Calculation

The mean convective heat transfer coefficient kc for flat plate is calculated through the corresponding Nusselt number Nu_turb according to [VDI 2002, p. Gd 1, eq. 2]:

```    Nu_turb = (0.037 * Re^0.8 * Pr) / (1 + 2.443/Re^0.1 * (Pr^(2/3)-1))
```

and the corresponding mean convective heat transfer coefficient kc :

```    kc =  Nu_turb * lambda / L
```

with

 cp as specific heat capacity at constant pressure [J/(kg.K)], eta as dynamic viscosity of fluid [Pa.s], kc as mean convective heat transfer coefficient [W/(m2.K)], lambda as heat conductivity of fluid [W/(m.K)], L as length of plate [m], Nu_turb as mean Nusselt number for turbulent regime [-], Pr = eta*cp/lambda as Prandtl number [-], rho as fluid density [kg/m3], Re = v*rho*L/eta as Reynolds number [-].

#### Verification

The mean Nusselt number in turbulent regime Nu representing the mean convective heat transfer coefficient kc for Prandtl numbers of different fluids is shown in the figure below.

#### References

VDI:
VDI - Wärmeatlas: Berechnungsblätter für den Wärmeübergang. Springer Verlag, 9th edition, 2002.

Extends from `Modelica.​Icons.​Information` (Icon for general information packages).