# The Development of a Forage Harvester Ensuring Two-Level Moving of Tall Stalk Forage
## 3 Materials and Methods of Research
### Determination of the Required Power of the Feeding Screw and the Orienting Drum
\begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline \begin{tabular}{c} **Velocity v,** \\ **m/s** \\ \end{tabular} & \begin{tabular}{c} **Output, Q,** \\ **t/h** \\ \end{tabular} & \begin{tabular}{c} **Power, N,** \\ **kW** \\ \end{tabular} & \begin{tabular}{c} **Power Variation Range** \\ **Under Repeated** \\ **Measurements, kW** \\ \end{tabular} & \begin{tabular}{c} **Energy** \\ **Capacity,** \\ **E, kWh/t** \\ \end{tabular} & \begin{tabular}{c} **Losses, \%** \\ **\end{tabular} & \
\begin{tabular}{c} **Fraction, F** \\ **\% up to 100 mm** \\ \end{tabular} &
\begin{tabular}{c} **Average** \\ **Length, \(L_{ave}\)** \\ \end{tabular} \\ \hline
0.67 & 13.5 & 12.1 & 11.92–12.25 & 0.9 & - & 85.24 & 55.95 \\ \hline
0.8 & 16.3 & 13.5 & 13.37–13.62 & 0.84 & - & 85.24 & 55.95 \\ \hline
0.91 & 18.35 & 23.3 & 23.17–23.47 & 1.27 & 3.0 & 85.24 & 55.95 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Harvester performance results during moving and shredding of corn stalks. Figure 11: Harvester performance during moving and shredding of corn stalks. The results of the experimental studies also confirm the reliability of the proposed graphical model for single-rotor mowing and for theoretical investigations related to the two-level mowing of tall-stemmed crops. In this case, experiments on mowing tall maize stalks were conducted at various forward speeds of the machine, ranging from 0.67 to 0.91 m/s. At the beginning of the field trials, different travel speeds were selected to assess the harvester's operational feasibility. For instance, in [16], a speed of 1.0 m/s was identified as the optimal forward speed for a trailed forage harvester. In reality, the speed of the machine is selected depending on the type of plants to be mown and their yield. There are recommendations in the literature for selecting machine speeds for trailed combines:  
* When working with high-yielding and wet forage (e.g., maize for silage)--0.42-0.83 m/s (1.5-3.0 km/h);
* When harvesting hay or less dense mass--0.83-1.39 m/s (3.0-5.0 km/h);
* When working in light conditions (dry mass, flat terrain, low grass)--up to 1.67 m/s (up to 6.0 km/h) [24; 25]. Hence, it can be seen that the selected speeds of the machine correspond to the recommendations for moving high-yielding maize stalks. For the field experiments, the circumferential speeds of the mowing and chopping rotors were selected in accordance with the circumferential speeds of the cutting drums, as well as the mowing and chopping rotors of existing forage harvesters. For example, the following forage harvesters have cutting drums with circumferential speed as detailed: Jaguar-830 Claas--39.56 m/s; FX 307 New Holland--39.23 m/s; BiGXV12, Krone--37.99 m/s. Hence, it can be seen that in existing forage harvesters, the circumferential speeds of cutting drums are within 37.99-39.56 [13]. In addition, the circumferential speeds of mowing and chopping rotors of trailed forage harvesters are within 35-40 m/s [15]. Thus, the above-mentioned circumferential speeds of chopping and mowing working bodies provide mowing and chopping of all types of grasses and plants, including high-growing and wet crops, at permissible energy consumption and minimum losses. Therefore, the same tractor engine speed was set in all field trials, regardless of the speed of the machine. In this case, the tractor PTO speed and the rotational speed of the blade chopping rotor were equal to 850 rpm (linear speed of radial knives--35.6 m/s), and the rotational speed of the mowing rotors was 1250 rpm (linear speed of knives--36.9 m/s). Therefore, in the field experiments, the cutting speeds of the mowing and chopping rotors were set at the same level and were equal to the circumferential speeds of the chopping drums and rotors of existing machines. The speed of mass feeding by the orienting drum into the chamber of the shredding rotor also had a constant value. At the speed of rotation of the orienting drum of 170 rpm, with a diameter at the ends of the feeding fingers of 0.32 m, the speed of mass feeding was equal to 2.85 m/s.