Aug 2026· INMATEH Agricultural Engineering· 0 citations· 2 references
Abstract
To address the problems of low bale-forming rate and loose compaction during the mechanized recovery of
residual plastic film in farmland, a three-stage residual film baling device was developed. Based on the discrete
element method (DEM), a flexible thin-shell model of the residual film was established, and dynamic simulation
and parameter optimization of the baling process were carried out using Rocky DEM software. Combined with
single-factor experiments and response surface methodology, the effects of baling chamber inclination angle,
belt type, belt linear speed, and upper belt inclination angle on bale integrity and compaction were analyzed.
The results showed that the bale-forming rate of the three-stage device reached 99.13%, and the bale density
reached 83.75 kg/m³ under the optimal conditions: baling chamber inclination angle of 30°, upper belt
inclination angle of 30°, belt linear speed of 2.3 m/s, and the use of a rough-surface belt. Field validation tests
showed that the average density of the residual film bales was 91.4 kg/m³, with a prediction error of only 2.23
kg/m³ compared with the simulation results. The device operated stably and reliably. This study presents a
high-efficiency residual film baling device with improved bale-forming rate and compaction performance
through structural optimization and parameter tuning, providing technical support for efficient recovery and
pollution control of residual plastic film in farmland.
This study investigates the influence of technological parameters on the strength of polypropylene (PP) film seals used in industrial packaging applications. The effects of sealing temperature, sealing time, and jaw clamping pressure on seal strength were analyzed using a five-level response surface experimental design supported by finite element simulations and regression-based optimization. A polynomial regression model with a coefficient of determination of R² = 0.9203 was developed to predict seal strength. The results demonstrated that sealing temperature and sealing time were the dominant process parameters affecting joint strength, while jaw pressure had a comparatively minor influence within the investigated range. No effective seal formation was observed below approximately 100 °C. The optimal process parameters were identified as T = 141.14 °C, t = 2.14 s, and p = 4.65 bar, resulting in an experimentally verified maximum joint strength of Fmax = 33.7 ± 0.4 N. The proposed experimental-numerical methodology can support the optimization of industrial PP film sealing processes and facilitate the selection of process parameters for similar packaging applications.
R. Patyk, Ł. Bohdal, P. Kałduński et al.· Scientific Reports· 0 citations
This paper presents the results of an experimental study on high-speed milling of the VT1–0 titanium alloy. A solid carbide end mill, MC089, with a diameter of 16 mm, was used as the cutting tool. The results indicated that the influence of the cutting parameters on the machined surface roughness is complex. An increase in spindle speed has a positive effect on surface roughness, whereas an increase in feed rate and depth of cut has a negative effect. The optimal cutting parameters were determined as follows: spindle speed nsp=4200 rot/min, depth of cut t=1 mm, and feed rate S=4500 mm/min. A numerical modeling methodology was developed to determine the optimal cutting parameters for the same process. A three-dimensional model of the "tool–workpiece" system was developed using KOMPAS-3D and ANSYS Workbench, and the Johnson–Cook material failure model was selected. The contact interaction was defined, and a finite element model was developed. A numerical design of experiments was carried out using a rational planning method with variation of the main machining parameters, including depth of cut, feed rate, and spindle speed. As a result, temperature fields, contact forces, and plastic strain distributions were obtained. In addition, a mathematical model was developed to predict the workpiece temperature as a function of machining parameters. The minimization of the objective function enabled identifying the optimal cutting parameters that ensure minimal thermal impact: depth of cut t = 1 mm, feed rate S = 4500 mm/min, and spindle speed nsp = 4162 rot/min. Comparison with the experimental results showed a slight discrepancy in the optimal cutting values. The proposed methodology can be used to reduce the cost of conducting physical experiments and improve machining efficiency.
K. Sherov, Zhanara Mussina, Assylbek Kassenov et al.· Engineering, Technology &...· 0 citations
To address the challenges of procedural complexity, the lack of an integrated heating–forming capability, and poor formability in the hot forming of titanium alloy skin components, an electrically assisted forming (EAF) process is proposed. A Johnson–Cook constitutive model was established to characterize the flow behavior of Ti–6Al–4V alloy under electric-assisted conditions, achieving a correlation coefficient of 0.968 and an average relative error of 7.67%. Forming parameters were investigated through a combined approach of numerical simulation and experimentation. At a current density of 7.59 A/mm2, a forming speed of 1 mm/min, and a friction coefficient of 0.1, the maximum springback of the component was 1.04 mm. Compared with isothermal forming, the EAF process reduced the springback by 7.14% and enhanced the ultimate tensile strength by 5.34%. Microstructural characterization revealed that, under pulsed current, the α-phase grains of the material were refined, whereas the β-phase fraction and the average grain size increased, accompanied by a 15.3% reduction in the geometrically necessary dislocation (GND) density. This study validates the process feasibility of electrically assisted forming for thin-walled titanium alloy skin components.
This paper proposes a labyrinth-finger seal designed for high-pressure differential and high-speed operating machinery, with an emphasis on its thermal-fluid behavior and multi-objective optimization. A two-dimensional axisymmetric numerical model is established. In this model, the upstream labyrinth teeth are simulated using conventional flow modeling, and the downstream finger section is modeled as a porous medium and solved with the RNG k-ε turbulence model. Frictional heat generation at the contact interface between the finger boot and rotor is incorporated. Leakage rate and peak temperature are adopted as evaluation metrics. Single-factor sensitivity analysis is first conducted to identify the dominant geometric parameters, specifically, tooth radial clearance, rear shield protection height, and number of finger plates. Subsequently, an L25 orthogonal array based on the Taguchi method is constructed to perform multi-objective optimization of six key factors. Results indicate that within the pressure differential range of 0.10–0.50 MPa and rotational speeds of 9,000–21,000 r/min, the optimized configuration achieves a leakage reduction of approximately 50% and a peak temperature decrease of 6–10 K. Flow field analysis revealed that leakage suppression arises from a synergistic mechanism: throttling energy dissipation at the labyrinth teeth combined with compliant flow restriction at the fingertip. Validation against published experimental data yields deviations within 10%, confirming the effectiveness of the combined CFD-Taguchi optimization approach. This methodology offers practical guidance for the engineering design of high‑performance composite seals.
H. W. Ma, M. Liu, J. Wang et al.· Journal of Applied Fluid Mec...· 0 citations
To identify the key factors affecting the sealing performance of a polished-rod sealing device under typical operating conditions, a beam pumping unit polished-rod sealing device was investigated in this study. Uniaxial tensile tests were performed on nitrile butadiene rubber, and the material constants of the two-parameter Mooney–Rivlin model were determined as C10=2.05411 and C01=0.10236. A two-dimensional axisymmetric finite element model was then established to analyze the effects of axial pressure, temperature, and friction coefficient on the contact pressure, stress, strain, and deformation of the sealing packing. The results show that axial pressure is the dominant factor affecting sealing performance. Within the axial pressure range of 2–12 MPa, the contact pressure increased significantly with increasing axial pressure. When the axial pressure reached 4 MPa, the average contact pressure at the sealing interface was 1.63 MPa, exceeding the wellhead pressure of 0.5 MPa and satisfying the sealing requirement. The recommended axial pressure range is 4–10 MPa. Within the temperature range of 20 °C–100°C, temperature had little effect on the contact pressure, stress, and strain distributions. In the friction coefficient range of 0.02–0.2, the contact pressure changed only slightly, while the friction force increased with increasing friction coefficient; when the friction coefficient reached 0.2, the maximum friction force was 1.0821 N. These results provide a theoretical basis for the structural optimization, material selection, and operating parameter design of polished-rod sealing devices.
Yu Zhao, Jinsong Wang, Siqi Huang et al.· Engineering Research Express· 0 citations
In order to provide a theoretical basis for the monitoring and control of the formation process of round bales, the friction test platform for the rolling formation of round bales was built to study the interaction between steel roll and material in the forming process. The results showed that the torque value of the steel roller at the lowest position (No. 2 steel roll) in the bale chamber was closely related to the forming process of the round bale. According to the change of the torque value, the forming process can be divided into an initial stage, straw core formation stage, compression stage and bale-forming stage. The change of torque value can be used for monitoring the forming process of round bales. During the forming process, materials were subject to sliding friction and rolling friction. From the initial stage to the forming stage, the friction of materials gradually changed from sliding friction to rolling friction, and the surface contacted between the material and the steel roll gradually changed to line contact. The interaction model of steel roll and material was established and verified; the model showed that the maximum error between the theoretical value and the experimental value of the forming density is 13.24% and the minimum error is 0.75%. The forming density of round bales was positively correlated with the mass of material fed per second and negatively correlated with the volume of the bale-forming chamber. The forming density of round bales can be expressed by the tangential force per unit length of No. 2 steel roll under the condition that the moisture content of material, the mass of material fed per second and the volume of the baling chamber were fixed. The model provides a theoretical basis for monitoring and controlling the forming process of round bales.
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