## 3 Workflow Description
### Output Generated  
The ultimate goal of T-WorkFlow is to provide the designer with a tool that can streamline and speed up the process of selection of the best configuration among those available. In this regard, the designer needs specific outputs that help evaluate both qualitatively and quantitatively the flow distribution within the radiant channels and the overall pressure drop across the radiator. During the software development, we chose to monitor the evolution of these two parameters throughout the simulation, as they are considered fundamental and representative of the radiator performance, especially in the initial design phase, for which the use of T-WorkFlow is intended. Distributing the fluid uniformly within the radiator channels ensures a more effective heat exchange, while minimizing pressure losses allows for more power to the engine, which can be converted into \"thrust\". In a design loop where performance must be maximized, improvements related to these two parameters enable the minimization of the heat exchange surface, allowing for the installation of a smaller and lighter radiator. This, in turn, ensures a less bulky sidepod, leading to reduced aerodynamic drag and, thus, more available power. Additionally, T-WorkFlow produces the text file Area_ratio, which is intended to assist the designer in assessing the ability of the computational grid, automatically generated, to accurately reproduce the actual area of the radiant channels. Within this file, the following parameter is given as a percentage:  
\[A_{rt}=\frac{\sum_{i=1}^{N}A_{m,i}}{A_{eff}}, \tag{10}\]  
where \(N\) indicates the number of channels, \(A_{m}\) is the area of the computational grid relative to the control surface defined for the \(i\)-th channel, and \(A_{eff}\) is the area of the cross-section of all the radiant channels obtained from the CAD model via the FreeCAD macro. T-WorkFlow also provides as output the following set of files to monitor during the simulation of the evolution of pressure losses and fluid distribution in the radiator channels:  
1. deltaP_inlet_outlet;
2. flowRate_Standard_Deviation;
3. charts update within flowRateVisualization. These are updated during the simulation whenever the solver reaches an iteration count that is a multiple of a user-defined value specified through the graphical interface \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline
**Boundary** & & \(\frac{P}{\rho}\left[\mathbf{m^{2}/s^{2}}\right]\) & \(\boldsymbol{U}\left[\mathbf{m/s}\right]\) & \(\boldsymbol{k}\left[\mathbf{m^{2}/s^{2}}\right]\) & \(\boldsymbol{c}\left[\mathbf{m^{2}/s^{2}}\right]\) & \(\boldsymbol{\omega}\left[\mathbf{1/s}\right]\) \\ \hline \multirow{2}{*}{Inlet} & Type: Value: & zeroGradient & fixedValue & fixedValue & fixedValue & inletOutlet \\  & Value: & / & \(U_{x};U_{y};U_{z}\) & \(k_{ifd}\) & \(\epsilon_{ifd}\) & \(\omega_{ifd}\) \\ \hline \multirow{2}{*}{Outlet} & Type: Value: & fixedValue & zeroGradient & inletOutlet & inletOutlet & inletOutlet \\  & Value: & uniform 0 & / & \(k_{ifd}\) & \(\epsilon_{ifd}\) & \(\omega_{ifd}\) \\ \hline \multirow{2}{*}{Walls} & Type: & zeroGradient & noSlip & kqRWF & epsilonWF & omegaWF \\  & Value: & / & / & \(k_{ifd}\) & \(\epsilon_{ifd}\) & \(\omega_{ifd}\) \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Boundary conditions imposition. (see Section 3.1). The first file contains the pressure drop \(\Delta\hat{p}_{in-out}=2(\bar{p}_{in}-\bar{p}_{out})/\left\|\mathbf{U}_{in}\right\|^ {2}\), evaluated across the inlet and outlet surface and normalized by a dynamic pressure computed with the magnitude of the velocity at the radiator inlet. \(\bar{p}_{in}\) and \(\bar{p}_{out}\) are, here, the integral averages of the pressures evaluated on the inlet and outlet surfaces. Notice that the incompressible solver _simpleFoam_ solves for the \(\bar{p}=p/\rho\) variable, where \(\rho\) is the fluid density.