# Analytical Calculation Model of the TV3-117 Turboshaft Working Regimes Based on Experimental Data
## 5 Calculated Results and Charts  
Following the application of the analytical calculation model based on similarity parameters, several main engine parameters and some performances at each engine regime of the TV3-117 MT turboshaft were determined. In Table 16 are presented the calculated actual values of the engine parameters and performance. The foundation of the analytical calculation model is the percentage variation in similarity parameters. In Table 17 are shown the percentage variation values (\(\Delta\mathit{prm}_{c}\)) of the calculated parameters and performances from Table 16. The values were calculated by reporting all values from each regime to the values of the takeoff regime, and also by applying the Equation (1). \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline
**Engine Regimes** & **NG [\%]** & \(\boldsymbol{M_{af}}\) **[kg/s]** & \(\boldsymbol{\pi_{Ct}}\) **[-]** & \(\boldsymbol{F_{f}}\) **[kg/s]** & \(\boldsymbol{T_{3t}}\) **[\({}^{\circ}\)K]** & \(\boldsymbol{P}\) **[HP]** & \(\boldsymbol{\eta_{te}}\) **[-]** \\ \hline Takeoff & 97.6 & 7.652 & 9.6 & 0.142 & 1248 & 2225 & 0.2687 \\ Takeoff (L) & 96.1 & 7.391 & 9.121 & 0.130 & 1210 & 1972 & 0.260 \\ Nominal & 94.7 & 7.043 & 8.557 & 0.118 & 1175 & 1722 & 0.250 \\ Cruise 1 & 93.5 & 6.854 & 8.217 & 0.110 & 1145 & 1539 & 0.240 \\ Cruise 2 & 91.5 & 6.453 & 7.562 & 0.096 & 1097 & 1219 & 0.217 \\ Idle & 73.0 & 2.733 & 3.337 & 0.038 & 862 & 252 & 0.1145 \\ \hline \hline \end{tabular}
\end{table} 
Table 16: The calculated values of the TV3-117 MT parameters at each regime. \begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline
**Engine Regimes** & **NG [\%]** & \(\boldsymbol{\Delta M_{af}}\) **[\%]** & \(\boldsymbol{\Delta\pi_{Ct}}\) **[\%]** & \(\boldsymbol{\Delta F_{f}}\) **[\%]** & \(\boldsymbol{\Delta T_{3t}}\) **[\({}^{\circ}\)\%]** & \(\boldsymbol{\Delta P}\) **[\%]** & \(\boldsymbol{\Delta\eta_{te}}\) **[\%]** \\ \hline Takeoff & 97.6 & 100 & 100 & 100 & 100 & 100 & 100 \\ Takeoff (L) & 96.1 & 96.59 & 95.01 & 91.55 & 96.96 & 88.63 & 96.76 \\ Nominal & 94.7 & 92.04 & 89.14 & 83.10 & 94.15 & 77.39 & 93.04 \\ Cruise 1 & 93.5 & 89.57 & 85.59 & 77.46 & 91.75 & 69.17 & 89.32 \\ Cruise 2 & 91.5 & 84.33 & 78.77 & 67.61 & 87.90 & 54.79 & 80.76 \\ Idle & 73.0 & 35.72 & 34.76 & 26.76 & 69.07 & 11.33 & 42.61 \\ \hline \hline \end{tabular}
\end{table} 
Table 17: Percentage values (\(\Delta\mathit{prm}_{c}\)) of TV3-117 MT calculated main data. To have a graphical view about parameter variation, in the next figures from the displays in Figures 4-7, under the charts, except the takeoff point, the percentage variations of the main engine parameters performances, such as mass air flow (\(M_{\text{{\it{q}}}d}\)), fuel flow (\(F_{\text{{\it{f}}}}\)), overall total pressure ratio (\(\pi_{CI}\)), and turbine inlet total temperature (\(T_{3t}\)), gas generator turbine total-specific actual work (\(l_{TG}\)), free turbine total-specific actual work (\(l_{TP}\)), engine shaft power (\(P\)), and thermal efficiency (\(\eta_{te}\)) with the engine speed are shown. Figure 4: (**a**) Percentage variation in mass air flow (\(\text{M}_{\text{{\it{af}}}}\)) and fuel flow (\(\text{F}_{\text{{\it{f}}}}\)) with engine speed. (**b**) Percentage variation in overall total pressure ratio (\(\pi_{CI}\)) and turbine inlet total temperature (\(T_{3t}\)), with engine speed. Figure 5: (**a**) Percentage variation in gas generator turbine total-specific actual work (\(l_{TG}\)) and free turbine total-specific actual work (\(l_{TP}\)) with engine speed. (**b**) Percentage variation in engine shaft power (\(P\)) and thermal efficiency (\(\eta_{te}\)) with engine speed. In Figure 4a, it is observed that the curve variation in the air mass flow is similar with the fuel flow but with higher percentage values than the fuel flow. At the idle regime, the air mass flow starts to vary from 36% compared to 27% of the fuel flow. In Figure 4b, it is noticed that the overall total pressure ratio of the curve variation is different than the turbine inlet total temperature.