## 5 Experimental Results and Calculated Data
The mass air flow relation is:  
\[M_{af}=\rho_{s}.V.A \tag{7}\]  
The overall pressure ratio and turbine total pressure ratio relations are:  
\[\pi_{Cl}=P_{2t}/P_{1t} \tag{8}\]  
\[\pi_{Tt}=P_{3t}/P_{45t} \tag{9}\]  
The compressor and turbine total adiabatic efficiency relations are:  
\[\eta_{Ct}=l_{Cl.id}/l_{Cl}=\frac{h_{2t,id}(T)-h_{1t}(T)}{h_{2t}(T)-h_{1t}(T)} \tag{10}\]  
Figure 10:0  
The gases flow relation is:  
Figure 10:1  
The thermal efficiency, depends on the fuel lower heating value (\(L_{HVf}\)), with the next form:  
Figure 10:2  
Because the engine was tested with Jet A-1 fuel the value of \(L_{HV}\) is 42, 900 [kJ/kg]. In Tables 4 and 5, are presented the calculated values of engine parameters in the main stations and some performances of engine components. In order to achieve a better view of the engine parameter variation the percentage variation was calculated by reporting all the parameters values of each engine regime (R) at parameter value from the maximum regime (d), in this case from the 99.11% engine speed regime, as is shown in the equation (14). So, in that mode it is obtained an easier method of perception about the parameters (\(prm\)) and performances variation. Figure 10:3  
In the first case the percentage variation of the engine regimes from engine manual was studied as, presented in Figure 10:4  
Table 7, the calculated percentage values of engine main engine parameters and certain performances of engine components are presented. \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline
**Regime** & **P [\%]** & **S\({}_{\text{FC}}\) [\%]** & **N\({}_{\text{GG}}\) [\%]** & **N\({}_{\text{TP}}\) [\%]** & **T\({}_{\text{3t,max}}\) [\%]** & **F\({}_{\text{C}}\) [\%]** \\ \hline Idle (a) & 6.67 & 363.64 & 63 + 2/\(-\)1 & 47.2 + 10 & 62.86 & 24.24 \\ Cruise (b) & 66.67 & 112.73 & 94.5 & 99.7 + 2 & 92.57 & 75.15 \\ Max. Cont. (c) & 80.00 & 107.27 & 96 & 99.7 + 2 & 98.29 & 85.82 \\ Takeoff (d) & 100.0 & 100.0 & 98.5 & 97.6 + 1 & 100.0 & 100.0 \\ \hline \hline \end{tabular}
\end{table} 
Table 6: The percentage variation of the main engine parameters. \begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline
**Reg. nr.** & **N\({}_{\text{GG}}\) [\%]** & **F\({}_{\text{f}}\) [kg/s]** & **M\({}_{\text{df}}\) [kg/s]** & **T\({}_{\text{1t}}\) [K]** & **T\({}_{\text{2t}}\) [K]** & **\(\pi_{\text{CI}}\) [\(-\)]** & **\(\eta_{\text{CI}}\) [\(-\)]** & **G\({}_{\text{f}}\) [kg/s]** \\ \hline Idle (a) & 64.80 & 0.027 & 2.260 & 294.5 & 378.5 & 2.049 & 0.796 & 2.287 \\
1 & 83.40 & 0.045 & 4.023 & 294.7 & 442.3 & 3.240 & 0.793 & 4.068 \\
2 & 86.50 & 0.049 & 4.464 & 295.0 & 455.6 & 3.525 & 0.791 & 4.513 \\
3 & 89.40 & 0.060 & 5.151 & 295.3 & 474.2 & 4.041 & 0.804 & 5.211 \\
4 & 91.70 & 0.075 & 5.685 & 295.6 & 489.7 & 4.525 & 0.815 & 5.760 \\
5 & 93.80 & 0.078 & 6.182 & 296.0 & 506.3 & 5.024 & 0.817 & 6.620 \\
6 (b) & 95.50 & 0.088 & 6.586 & 296.3 & 515.9 & 5.383 & 0.825 & 6.674 \\
7 (c) & 97.00 & 0.097 & 6.967 & 296.7 & 526.9 & 5.747 & 0.826 & 7.064 \\
8 & 98.40 & 0.108 & 7.307 & 297.0 & 537.7 & 6.087 & 0.824 & 7.415 \\
9 (d) & 99.11 & 0.109 & 7.436 & 297.5 & 540.6 & 6.225 & 0.830 & 7.545 \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Calculated data at each engine working regime, part one. \begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline
**Reg. nr. ** & **N\({}_{\text{GG}}\) [\%]** & **P\({}_{\text{3t}}\) [bar a]** & **T\({}_{\text{3t}}\) [K]** & **T\({}_{\text{4t}}\) [K]** & **T\({}_{\text{45t}}\) [K]** & **\(\pi_{\text{TI}}\) [\(-\)]** & **\(\eta_{\text{TI}}\) [\(-\)]** &  
From the chart it can be observed that the fuel flow and mass air flow increase with engine speed and have almost the same curves variation but with different values until 95% speed regime. Figure 12 presents the overall pressure ratio (\(\pi_{Ct}\)) and inlet turbine total temperature (\(T_{3t}\)) percentage variation with engine speed.