## 4 Case Study: Reliability Analysis of a Diesel Engine
### Establishment of RDFTA for the Diesel Engine at the Component Level  
The electronic control system of a diesel engine is a device that monitors its operational state. During the operation of a diesel engine, the electronic control system can monitor changes in the diesel engine operation in real time, provide timely feedback on the conditions that are caused by the diesel engine, and take corresponding measures to alleviate those conditions. The working principles of the intake and exhaust and supercharger systems are as follows: the exhaust pipe is connected to the turbine shell and high-temperature exhaust gas that has a certain pressure and flow rate and is discharged from the engine impacts the turbine in a certain direction through the turbine shell, causing the turbine to rotate at a high speed. Higher pressures lead to greater temperatures and speeds of the exhaust gas, as well as a higher turbine speed. The exhaust gas is then finally discharged into the atmosphere. The compressor impeller that is coaxial with the turbine shaft also sucks the air that is passing through the air filter into the compressor at the same speed. The interactions between the pressurization and electronic control system components are shown in Figure 12.  
According to the comprehensive severity score of the FMECA-FHA model, the RDFTA (with the diesel engine supercharger and electronic control system failures as the top events) was produced. Figure 12 indicates the following faults: a system fault T; an output fault of the pressurization and intake and exhaust systems T_1; an exhaust manifold fault A; a fault in the exhaust bypass valve B; an exhaust system failure C; a turbine failure D; a compressor failure E; an air filter failure F; a pressurization system failure G; an air intake system failure H; a control system failure T_2; a power failure I; a startup fault J; a controller failure K; and an actuator failure 50. Table 10 shows the reliability parameters of the pressurization, intake and exhaust, and control systems. Figure 12: A schematic diagram of the pressurization and electronic control systems. \begin{table}
\begin{tabular}{c c c c c c c c} \hline
**RDPTA** & **Unit Name** & **Failure Rate** & **Maintenance Rate** & **RDPTA** & **Unit Name** & **Failure Rate** & **Maintenance Rate** \\
**Number** & \(10^{-3}(\mathbf{k}^{-1})\) & \((\mathbf{k}^{-1})\) & **Number** & **Number** & \(10^{-3}(\mathbf{k}^{-1})\) & \((\mathbf{k}^{-1})\) \\ \hline \(x_{1}\) & Air input & 0.32 & 0.92 & \(x_{13}\) & Air flow sensor & 0.08 & 0.4 \\ \hline \(x_{2}\) & Engine exhaust gas input & 0.75 & 1.48 & \(x_{14}\) & Air inlet heating device & 0.03 & 0.98 \\ \hline \(x_{3}\) & Air filter & 0.34 & 1.65 & \(x_{15}\) & Start signal & 0.082 & 1.3 \\ \hline \(x_{4}\) & E exhaust manifold & 0.28 & 0.9 & \(x_{16}\) & Control signal & 0.07 & 1.5 \\ \hline \(x_{5}\) & Bypass valve control device & 0.25 & 0.74 & \(x_{17}\) & Pedal signal & 0.05 & 0.8 \\ \hline \(x_{6}\) & E exhaust bypass valve & 0.75 & 1.4 & \(x_{18}\) & Dialogue device & 0.064 & 0.5 \\ \hline \(x_{7}\) & Turbine & 7.8 & 1.5 & \(x_{19}\) & Power supply & 0.04 & 0.6 \\ \hline \(x_{8}\) & Rotor shaft & 0.2 & 0.8 & \(x_{20}\) & Emergency power supply & 0.04 & 0.6 \\ \hline \(x_{9}\) & Compressor & 0.42 & 0.85 & \(x_{21}\) & Controller & 0.05 & 1.5 \\ \hline \(x_{10}\) & Intercooler & 0.3 & 0.5 & \(x_{22}\) & Sensor system & 0.01 & 0.85 \\ \hline \(x_{11}\) & Intake manifold & 0.31 & 0.73 & \(x_{23}\) & Actuator & 0.022 & 0.96 \\ \hline \(x_{12}\) & Intake bypass valve & 0.53 & 0.97 & & & & \\ \hline \end{tabular}
\end{table} 
Table 10: The RDFTA reliability parameters of the pressurization and control system components. The quantitative reliability analysis of the supercharger, intake and exhaust, and control systems was carried out using the Monte Carlo simulation method [51].