## 3 Problem Configuration  
As stated in the Introduction, the methodology followed in this work involves the comparison between the reference model and its theoretical equivalent. Two AUVs are deemed to be equivalent if they have the same characteristics insofar as sensors, cruising speed, maximum navigation depth, and size. This principle includes restrictions in the configuration of DMFC-AUV\QpDM which are described below.  
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Parameter** & **Description** & **Value** & **Reference** \\ \hline \hline \multirow{3}{*}{_depth_ (m) & Maximum operating depth & Model 1000: 1000 & \\  & & Model 3000: 3000 & \\  & & Model 4500: 4500 & \\ \(\mu\)_thMat_ & PH building material & Titanium ASTM B265 Gr. 5 & [25] \\ \(\rho_{\mathrm{ph}}\) (kg/m\({}^{3}\)) & PH building material density & 4420 & [25] \\ \(E_{\mathrm{ph}}\) (GPa) & PH building material modulus of elasticity & 105 & [25] \\ \(\sigma_{\mathrm{ph}}\) & PH building material Poisson’s module & 0.31 & [25] \\ \(hMat\) & External hull material & Carbon fiber & \\ \(\rho_{\mathrm{h}}\) (kg/m\({}^{3}\)) & External hull material density & 1330 & [48] \\ \(n\) & Myring index & 2.5 & \\ \(\alpha\) (\({}^{\circ}\)) & Exit angle at the stern cone & 8 & \\ \(thk_{\mathrm{full}}\) (mm) & Thickness of the external hull & 10 & \\ \(k_{\mathrm{s}}\) (\(\mu\)m) & Surface roughness & 150 & [22] \\ \(C_{\mathrm{d}Mrg}\) & Drag coefficient margin & 0.6 & [20] \\ \(\
u_{\mathrm{p}np}\) & Propulsion efficiency & 0.50 & [49] \\  & & Model 1000: 420 & \\ \(\rho_{\mathrm{g}atum}\) (kg/m\({}^{3}\)) & Syntactic foam density & Model 3000: 435 & [50] \\  & & Model 4500: 505 & \\ \(MrgVol_{0}\) & Volume margin in central PH & 0.20 & \\ \(MrgMass_{0}\) & Weight margin & 0.05 & \\ \(maxNStacks\) & Maximum number of stacks & 2 & \\ \(maxNStref\) & Efficiency of the methanol storage system & 0.95 & \\ \(\rho 2 StorSpecW\) (kg\({}_{\mathrm{O}}\)/kg\({}_{\mathrm{system}}\)) & O\({}_{2}\) storage system, specific weight & 0.520 & [51] \\ \(\omega 2 StorSpecV\) (kg\({}_{\mathrm{O}}\)/m\({}^{3}\) system) & O\({}_{2}\) storage system, specific volume & 336 & [51] \\ \(\rho_{\mathrm{O}_{2}}\) (kg/m\({}^{3}\)) & Density of stored O\({}_{2}\) at 288.15 K and 35 MPa & 463.67 & [52] \\ \(\rho\) (kg/m\({}^{3}\)) & Sea water density at 288 K and 100 kPa & 1026.021 & [53] \\ \(\mu\) (\(\mu\)Pa-s) & Sea water dynamic viscosity 288 K and 100 kPa & 1220 & [53] \\ \(c_{\mathrm{d}COH}\) (M) & Methanol concentration in anode solution & 3\%wt & \\ \(\rho_{\mathrm{d}COH}\) (kg/m\({}^{3}\)) & Methanol density at 288 K and 100 kPa & 795.69 & [52] \\ \(M_{\mathrm{d}MCH}\) (kg/kmol) & Methanol molar mass & 32.042 & [52] \\ \(M_{\mathrm{CO}_{2}}\) (kg/kmol) & CO\({}_{2}\) molar mass & 44.04 & [52] \\ \(\rho_{H_{2}O}\) (kg/m\({}^{3}\)) & Pure water density at 288 K and 100 kPa & 999.10 & [52] \\ \(M_{H_{2}O}\) (kg/kmol) & Pure water molar mass & 18.015 & [52] \\ \(\rho_{\mathrm{ads}}\) (kg/m\({}^{3}\)) & Adsorbent density & Zeolite 13X: 689 & [44,45] \\  & & Mg-MOF-74: 909 & \\ \(adsCapRt\) (moles\({}_{\mathrm{CO}_{2}}\)/g\({}_{\mathrm{adsorbent}}\)) & Ad sorbent capture capacity & Zeolite 13X: 3.25 & \\  & at \(T_{\mathrm{ads}}\) = 318 K and \(p_{\mathrm{ads}}\) = 100 kPa & Mg-MOF-74: 8 & [44,45] \\ \(buttSpecPw\) (W/kg) & Li-Ion Battery specific power & 150.0 & [54] \\ \(buttSpecE\) (kJ/kg) & Li-Ion Battery specific energy & 540.0 & [55] \\ \(buttERhto\) (MJ/m\({}^{3}\)) & Li-Ion Battery energy density & 1274.0 & [55] \\ \hline \hline \end{tabular}
\end{table}
Table 4: Input parameters of the genetic algorithm (GA). PH, pressure hull.