Cooldt calculate the cooling duration of a multi-layers pipe in a cold environment. The duration to reach the “Final fluid temperature” or *cool-down time* (CDT) is calculated by solving the heat equation in cylindrical coordinates with a flux conservative formulation.

**↓↓ DOWNLOAD Cooldt 2 for Windows 32 / 64 bits ↓↓**

**↓↓ DOWNLOAD Cooldt 2 for Linux 64 bits ↓↓**

↓↓ DOWNLOAD Cooldt 2 sources ↓↓

- Flux Conservative Formulation of Transient Heat Transfer
- Automatic meshing and time step calculation (0.1% accuracy)
- LibreOffice and Excel interfaces
- Excel Add-in and Visual Basic interface
- Gnuplot compatible output
- 32 and 64 bits versions

- Gnu/Linux or Windows (or any operating system if you compile Cooldt from source)
- Recommended: LibreOffice or Excel
- Optional: Gnuplot

Download Gnu/Linux 64 bits or Windows 32/64 bits binaries version and extract the archive.

To install the Excel Add-in, follow these instructions. For the 32 bits version of Excel select **cooldt.xll** and for the 64 bits version of Excel select **cooldt-w64.xll**. No administrative privilege are required to install it.

Open CooldtSheet.xls or CooldtSheet.ods, enter your data then click the **Launch cooldt** button.

*The cooldt executable and the spreadsheet must be in the same folder and the decimal separator must be the point (.)*

*On Windows, Cooldt can not run on an UNC path (i.e. a path starting with \\). Map your UNC path, or run Cooldt from a local drive to solve this problem*

The Excel Add-in provides a native Excel function to calculate cool-down time. It is very useful to calculate an insulation thickness for a given cool-down time with the Excel solver. Avoid goal seek, it does not work very well with non-linear functions. To use the *CoolDownTime* function, click on the * fx* button on the formula bar, select the

Type `cooldt example.dat`

to calculate the cool-down time of the `example.dat`

data file. Results will be saved to the `example.txt`

file.

*Replace cooldt by cooldt-w64 if you are using the 64 bits version of Windows.*

The data file is a text file with numbers separated by spaces or tabs. The file format is presented in the table below:

InitialTemp.(°C) | AmbientTemp.(°C) | FinalTargetTemp.(°C) | AmbientHeatTransfer(W/m2/K) |

Pipe.ID(m) | FluidConductivity.(W/m/K) | FluidDensity(kg/m3) | FluidHeatCapacity(J/kg/K) |

Layer.1.OD(m) | Layer.1.Conductivity.(W/m/K) | Layer.1.Density(kg/m3) | Layer.1.HeatCapacity(J/kg/K) |

… | … | … | … |

Layer.n.OD(m) | Layer.n.Conductivity.(W/m/K) | Layer.n.Density(kg/m3) | Layer.n.HeatCapacity(J/kg/K) |

Several files can be processed in one command, *e.g.* type `cooldt file-1.dat file-2.dat file-3.dat`

to process three files.

To generate png and svg plots from a Cooldt output file, use the `gnuplot-script.gp`

script file with the Gnuplot command:

`gnuplot -e "OutputFile='example.txt';" gnuplot-script.gp`

Download the source code, extract the archive and follow these instructions.

Cooldt includes XLW – A Wrapper for the Excel API

Yes. Cooldt is a free software. Read the license for details.

On Windows, Cooldt can not run on an UNC path (*i.e.* a path starting with \\). Map your UNC path, or run Cooldt from a local drive to solve this problem.

Since Windows Vista and Excel 2007, it is %APPDATA%\Microsoft\AddIns. The following command should open this folder:

`explorer.exe %APPDATA%\Microsoft\AddIns`

Replace the old .xll file with new one in the add-in folder.