# Analysis of Dimensional Tolerances on Hydraulic and Acoustic Properties of a New Type of Prototypal
## 3 Measuring Rig
### Application of Neural Network in Extracting Measurement Points
\begin{table}
\begin{tabular}{c c c c c c c c c} \hline \hline
**n** & **Pt** & **Qzz** & **M** & **Nh** & **Nm** & **nv** & **nhm** & **nc** \\ (**rpm**) & **(MPa)** & **(/min)** & **(Nm)** & **(kW)** & **(kW)** & **(\%)** & **(\%)** & **(\%)** \\ \hline \multirow{9}{*}{500} & 0 & 15.1 & 2.0 & 0.00 & 0.10 & 94.4 & 0.0 & 0.0 \\  & 5 & 13.1 & 25.5 & 1.08 & 1.34 & 81.7 & 99.5 & 81.2 \\  & 10 & 11.4 & 52.5 & 1.89 & 2.75 & 71.2 & 96.8 & 68.9 \\  & 15 & 10.0 & 81.0 & 2.50 & 4.24 & 62.5 & 94.2 & 58.9 \\  & 20 & 9.5 & 110.0 & 3.17 & 5.76 & 59.6 & 92.5 & 55.1 \\  & 24 & 9.4 & 139.0 & 3.89 & 7.28 & 58.4 & 91.5 & 53.5 \\  & 30 & 8.6 & 172.0 & 4.30 & 9.01 & 53.8 & 88.8 & 47.7 \\ \hline \multirow{9}{*}{1000} & 0 & 31.7 & 2.2 & 0.00 & 0.23 & 99.2 & 0.0 & 0.0 \\  & 5 & 30.4 & 25.5 & 2.53 & 2.67 & 95.1 & 99.5 & 94.6 \\  & 10 & 28.8 & 53.0 & 4.79 & 5.55 & 89.9 & 95.9 & 86.2 \\  & 15 & 27.6 & 81.5 & 6.88 & 8.53 & 86.1 & 93.6 & 80.6 \\  & 20 & 26.5 & 108.0 & 8.84 & 11.31 & 82.9 & 94.2 & 78.1 \\  & 24 & 26.3 & 140.0 & 10.93 & 14.66 & 82.1 & 90.9 & 74.6 \\  & 30 & 25.4 & 172.0 & 12.70 & 18.01 & 79.5 & 88.8 & 70.5 \\ \hline \multirow{9}{*}{1500} & 0 & 48.0 & 2.8 & 0.00 & 0.44 & 100.0 & 0.0 & 0.0 \\  & 5 & 47.5 & 26.0 & 3.95 & 4.08 & 99.0 & 97.5 & 96.6 \\  & 10 & 45.7 & 56.5 & 7.60 & 8.87 & 95.2 & 90.0 & 85.6 \\  & 15 & 44.5 & 85.0 & 11.10 & 13.35 & 92.7 & 89.8 & 83.2 \\  & 20 & 43.5 & 113.0 & 14.47 & 17.75 & 90.5 & 90.1 & 81.5 \\  & 24 & 42.8 & 144.0 & 17.82 & 22.62 & 89.2 & 88.3 & 78.8 \\  & 30 & 41.9 & 176.0 & 20.92 & 27.65 & 87.2 & 86.8 & 75.7 \\ \hline \hline \multirow{9}{*}{2000} & 0 & 64.0 & 3.2 & 0.00 & 0.67 & 100.0 & 0.0 & 0.0 \\  & 5 & 63.5 & 27.5 & 5.27 & 5.76 & 99.3 & 92.2 & 91.5 \\ \cline{1-1}  & 10 & 61.9 & 56.6 & 10.30 & 11.83 & 96.8 & 90.0 & 87.1 \\ \cline{1-1}  & 15 & 60.8 & 85.0 & 15.19 & 17.80 & 95.0 & 89.8 & 85.3 \\ \cline{1-1}  & 20 & 59.8 & 113.0 & 19.92 & 23.76 & 93.5 & 90.1 & 84.2 \\ \cline{1-1}  & 24 & 59.1 & 143.0 & 24.59 & 29.95 & 92.3 & 89.0 & 82.1 \\ \cline{1-1}  & 30 & 58.0 & 177.0 & 29.00 & 37.07 & 90.7 & 86.3 & 78.2 \\ \hline \hline \end{tabular}
\end{table} 
Table 9: Results of the hydraulic measurements for the original pump [15], where: n—rotation speed, p(t)—discharge pressure, Qzz—flow rate, M—torque, Nh—hydraulic power, Nm—mechanical power, nv—volumetric efficiency, nhm—hydraulic and mechanical efficiency, nc—total efficiency. Other selected hydraulic (and acoustic) results for selected pumps were presented, e.g., in works [15; 17]. The comparison of the hydraulic performance for the pumps before modification show that the total efficiency of the currently produced gear pumps ranges from 74% to 88%. These values are lower than the efficiency of the prototype units by 4% to 18%. The increase in energy efficiency of the prototype units is mainly due to the relatively high internal tightness. The slightly higher efficiency of a unit with a fitting angle of \(c=130\) is due to the low hydraulic-mechanical torque loss. Even greater differences in the overall performance favor prototype pumps that are observed at low rotational speeds. This is due to a high drop in the volumetric efficiency of conventional pumps at speeds below \(n=800\) rpm. The volumetric efficiency of the conventional units did not exceed 60% for the nominal pressures, and rotational speed \(n=500\) rpm. The relatively high internal tightness of the prototype pumps ensures that the volumetric efficiency is maintained at a minimum of 90% throughout the pressure range, regardless of the rotational speed.