Package with records for solid materials. The material is characterized by its thermal conductivity, mass density and specific heat capacity.

These material records automatically compute the spatial grid that is used to compute transient heat conduction. In building materials, the thermal diffusivity of adjacent layer materials can differ by an order of magnitude. If the spatial grid generation were not to account for the material properties, then the time rate of change of the different temperature nodes would be significantly different from each other. Therefore, records in the packages Buildings.HeatTransfer.Data.Solids and Buildings.HeatTransfer.Data.SolidsPCM generate the spatial grid so that under the assumption of equal heat transfer, each node temperature has a similar time rate of change.

The computation is as follows:

From dimensionless analysis, one can obtain a characteristic time, called the *Fourier* number, as

Fo = α t ⁄ L^{2}

where *α* denotes the thermal diffusivity, *t* denotes time and *L* denotes the characteristic length.
We like to generate the spatial grid so that the ratio
*t ⁄ Fo*
is equal to an arbitrary constant
*Π*, which we define as

Π = ( t ⁄ Fo )^{1/2}

and hence

Π = L ⁄ √ α.

Now, let *x*
denote the thickness of the material layer.
Then, we compute the time constant of the material layer as

Π_{x} = x ⁄ √ α,

and we compute the estimated number of elements *N' ∈ ℝ*
for the material layer as

N' = N_{ref} Π_{x} ⁄ Π_{ref}

where *Π _{ref} ∈ ℕ* is a user-specified number of elements
for a reference material, which is equal to the parameter

`nStaRef`

, and defined as a concrete construction with thickness
Next, we define the number of elements for the material layer as

*N _{x} = ⌈ N' ⌉*

where the notation *⌈ ⋅ ⌉* is defined, for
*s ∈ ℝ*, as

⌈ s ⌉ = min{ k ∈ ℤ | k ≥ s }.

Finally, we divide the material layer in compartments of length
*Δ = x ⁄ N _{x}*.

Name | Description |
---|---|

Generic | Thermal properties of solids with heat storage |

Brick | Brick (k=0.89) |

Concrete | Concrete (k=1.4) |

InsulationBoard | Insulation board (k=0.03) |

GypsumBoard | Gypsum board (k=0.58) |

Plywood | Plywood (k=0.12) |

Generic record for solid materials. The material is characterized by its thermal conductivity, mass density and specific heat capacity.

Extends from Buildings.HeatTransfer.Data.BaseClasses.Material (Thermal properties of materials w/o storage).

Type | Name | Default | Description |
---|---|---|---|

Length | x | Material thickness [m] | |

ThermalConductivity | k | Thermal conductivity [W/(m.K)] | |

SpecificHeatCapacity | c | Specific heat capacity [J/(kg.K)] | |

Density | d | Mass density [kg/m3] | |

Real | R | x/k | Thermal resistance of a unit area of material [m2.K/W] |

Integer | nStaRef | 3 | Number of state variables in a reference material of 0.2 m concrete |

Boolean | steadyState | (c == 0 or d == 0) | Flag, if true, then material is computed using steady-state heat conduction |

Properties for phase change material | |||

Temperature | TSol | 293.15 | Solidus temperature, used only for PCM. [K] |

Temperature | TLiq | 293.15 | Liquidus temperature, used only for PCM [K] |

SpecificInternalEnergy | LHea | 0 | Latent heat of phase change [J/kg] |

Advanced | |||

Integer | nSta | max(1, integer(ceil(nStaReal... | Actual number of state variables in material |

Real | piRef | 331.4 | Ratio x/sqrt(alpha) for reference material of 0.2 m concrete |

Real | piMat | if steadyState then piRef el... | Ratio x/sqrt(alpha) |

Real | nStaReal | nStaRef*piMat/piRef | Number of states as a real number |

record Generic "Thermal properties of solids with heat storage" extends Buildings.HeatTransfer.Data.BaseClasses.Material(final R=x/k, final TSol=293.15, final TLiq=293.15, final LHea=0, final phasechange=false);end Generic;

Type | Name | Default | Description |
---|---|---|---|

Length | x | Material thickness [m] | |

ThermalConductivity | k | 0.89 | Thermal conductivity [W/(m.K)] |

SpecificHeatCapacity | c | 790 | Specific heat capacity [J/(kg.K)] |

Density | d | 1920 | Mass density [kg/m3] |

Integer | nStaRef | 3 | Number of state variables in a reference material of 0.2 m concrete |

Boolean | steadyState | (c == 0 or d == 0) | Flag, if true, then material is computed using steady-state heat conduction |

Advanced | |||

Integer | nSta | max(1, integer(ceil(nStaReal... | Actual number of state variables in material |

Real | piRef | 331.4 | Ratio x/sqrt(alpha) for reference material of 0.2 m concrete |

Real | piMat | if steadyState then piRef el... | Ratio x/sqrt(alpha) |

Real | nStaReal | nStaRef*piMat/piRef | Number of states as a real number |

record Brick = Buildings.HeatTransfer.Data.Solids.Generic ( k=0.89, d=1920, c=790) "Brick (k=0.89)";

Type | Name | Default | Description |
---|---|---|---|

Length | x | Material thickness [m] | |

ThermalConductivity | k | 1.4 | Thermal conductivity [W/(m.K)] |

SpecificHeatCapacity | c | 840 | Specific heat capacity [J/(kg.K)] |

Density | d | 2240 | Mass density [kg/m3] |

Integer | nStaRef | 3 | Number of state variables in a reference material of 0.2 m concrete |

Boolean | steadyState | (c == 0 or d == 0) | Flag, if true, then material is computed using steady-state heat conduction |

Advanced | |||

Integer | nSta | max(1, integer(ceil(nStaReal... | Actual number of state variables in material |

Real | piRef | 331.4 | Ratio x/sqrt(alpha) for reference material of 0.2 m concrete |

Real | piMat | if steadyState then piRef el... | Ratio x/sqrt(alpha) |

Real | nStaReal | nStaRef*piMat/piRef | Number of states as a real number |

record Concrete = Buildings.HeatTransfer.Data.Solids.Generic ( k=1.4, d=2240, c=840) "Concrete (k=1.4)";

Type | Name | Default | Description |
---|---|---|---|

Length | x | Material thickness [m] | |

ThermalConductivity | k | 0.03 | Thermal conductivity [W/(m.K)] |

SpecificHeatCapacity | c | 1200 | Specific heat capacity [J/(kg.K)] |

Density | d | 40 | Mass density [kg/m3] |

Integer | nStaRef | 3 | Number of state variables in a reference material of 0.2 m concrete |

Boolean | steadyState | (c == 0 or d == 0) | Flag, if true, then material is computed using steady-state heat conduction |

Advanced | |||

Integer | nSta | max(1, integer(ceil(nStaReal... | Actual number of state variables in material |

Real | piRef | 331.4 | Ratio x/sqrt(alpha) for reference material of 0.2 m concrete |

Real | piMat | if steadyState then piRef el... | Ratio x/sqrt(alpha) |

Real | nStaReal | nStaRef*piMat/piRef | Number of states as a real number |

record InsulationBoard = Buildings.HeatTransfer.Data.Solids.Generic ( k=0.03, d=40, c=1200) "Insulation board (k=0.03)";

Type | Name | Default | Description |
---|---|---|---|

Length | x | Material thickness [m] | |

ThermalConductivity | k | 0.16 | Thermal conductivity [W/(m.K)] |

SpecificHeatCapacity | c | 1090 | Specific heat capacity [J/(kg.K)] |

Density | d | 800 | Mass density [kg/m3] |

Integer | nStaRef | 3 | Number of state variables in a reference material of 0.2 m concrete |

Boolean | steadyState | (c == 0 or d == 0) | Flag, if true, then material is computed using steady-state heat conduction |

Advanced | |||

Integer | nSta | max(1, integer(ceil(nStaReal... | Actual number of state variables in material |

Real | piRef | 331.4 | Ratio x/sqrt(alpha) for reference material of 0.2 m concrete |

Real | piMat | if steadyState then piRef el... | Ratio x/sqrt(alpha) |

Real | nStaReal | nStaRef*piMat/piRef | Number of states as a real number |

record GypsumBoard = Buildings.HeatTransfer.Data.Solids.Generic ( k=0.16, d=800, c=1090) "Gypsum board (k=0.58)";

Type | Name | Default | Description |
---|---|---|---|

Length | x | Material thickness [m] | |

ThermalConductivity | k | 0.12 | Thermal conductivity [W/(m.K)] |

SpecificHeatCapacity | c | 1210 | Specific heat capacity [J/(kg.K)] |

Density | d | 540 | Mass density [kg/m3] |

Integer | nStaRef | 3 | Number of state variables in a reference material of 0.2 m concrete |

Boolean | steadyState | (c == 0 or d == 0) | Flag, if true, then material is computed using steady-state heat conduction |

Advanced | |||

Integer | nSta | max(1, integer(ceil(nStaReal... | Actual number of state variables in material |

Real | piRef | 331.4 | Ratio x/sqrt(alpha) for reference material of 0.2 m concrete |

Real | piMat | if steadyState then piRef el... | Ratio x/sqrt(alpha) |

Real | nStaReal | nStaRef*piMat/piRef | Number of states as a real number |

record Plywood = Buildings.HeatTransfer.Data.Solids.Generic ( k=0.12, d=540, c=1210) "Plywood (k=0.12)";

Automatically generated Thu Oct 24 15:10:40 2013.