## 3 Results and Discussion
The primary outcomes are presented in Tables 2-4. Checks were conducted for different objects under various conditions, reflecting the diverse characteristics of both the objects and the feasibility of experimental verification for fairly large full-scale objects. The results from the tables indicate that the checks yielded quite satisfactory outcomes, providing a solid basis to consider all the information presented here as reliable. The patterns identified for the simplest circuit can be extrapolated to more complex cooling system circuits if they incorporate the simplest circuit without modifications. However, there exist numerous cooling system schemes that utilize the concept of regulating the flow of ICC through heat exchangers, yet cool the coolants under conditions that do not align with those discussed above. \begin{table}
\begin{tabular}{l l c c c} \hline \hline \multirow{2}{*}{**Designation**} & \multirow{2}{*}{**Items**} & \multicolumn{2}{c}{**Values**} & \multirow{2}{*}{**Note**} \\ \cline{3-3} \cline{5-5}  & & **I** & **II** & **III** \\ \hline \(t_{2}\) & Air temperature after charge & 35.81 & 35.71 & 34.41 & Calculation \\  & air cooler (\({}^{\circ}\)C) & 35.70 & 35.52 & 34.12 & Experiment \\ \(\Delta t_{2}\) & Difference air temperature & 0.11 & 0.19 & 0.29 & \\  & after charge air cooler (\({}^{\circ}\)C) & 0.0157 & 0.0107 & 0.0095 & Calculation \\ \(\Delta p\) & Air resistance (bar) & 0.0150 & 0.0101 & 0.0090 & Experiment \\ \(\delta\) & Difference air resistance & 0.045 & 0.058 & 0.049 & \\ \(\eta_{c}\) & Charge air cooler efficiency & 0.94 & 0.95 & 0.97 & \\ \(G_{c}\) & Charge air flow (kg s\({}^{-1}\)) & 0.9 & 0.7 & 0.6 & Experiment \\ \(p_{1}\) & Boost pressure (bar) & 2.0 & 1.7 & 1.5 & Experiment \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Estimation of errors for charge air cooler. \begin{table}
\begin{tabular}{l l c c} \hline \hline \multirow{2}{*}{**Designation**} & \multirow{2}{*}{**Items**} & \multirow{2}{*}{**Calculation**} & \multirow{2}{*}{**Experiment**} \\ \hline \(G_{w}\) & ICC flow rate by fresh water pump (kg s\({}^{-1}\)) & 0.32 & \\ \(G_{ww}\) & ECC flow rate by sea water pump (kg s\({}^{-1}\)) & 5.50 & \\ \(t_{w1}\) & Inlet ICC water temperature (\({}^{\circ}\)C) & 91.46 & 91.40 \\ \(t_{w2}\) & Outlet ICC water temperature (\({}^{\circ}\)C) & 30.02 & 30.30 \\ \(t_{wv1}\) & Temperature of ECC in front of the cooler (\({}^{\circ}\)C) & 30.00 & 30.00 \\ \(\Delta p_{w}\) & Resistance by ICC (bar) & 0.00268 & 0.00305 \\ \(\Delta p_{uw}\) & Resistance by ECC (bar) & 0.00137 & 0.00123 \\ \(\delta_{w}\) & Error \(\Delta p_{w}\) & 0.139 & \\ \(\delta_{ww}\) & Error \(\Delta p_{uw}\) & 0.105 & \\ \(\eta_{w}\) & Central cooler efficiency & 0.999 & 0.995 \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Estimation of errors for central cooler. Below, we explore more complex systems in which the charge air cooler is integrated into the overall circuit, and another where it operates in a separate circuit. These systems are designed for an engine with parameters outlined in Table 5. Both circuits and their heat exchangers are state-of-the-art. The selected schemes are evaluated at \(\eta_{0}\) = 0.9. Since the definition of \(M_{\Sigma}\) is linked to specific designs of heat exchangers and types of heat exchange surfaces, the numerical values of the masses of the heat exchanger cores cannot be considered absolute, even for engines with similar parameters. However, the obtained mass values are convenient for comparing different options. The first of the cooling systems with a complex circuit is the type A cooling system (Figure 1). For this system, the highest value of the minimum \(M_{\Sigma}\) was obtained. The circuit is designed with a charge air cooling circuit integrated into the overall system circuit.