Zhengdian Xu

This study employs Principal Component Analysis (PCA) for comprehensive performance evaluation and establishes computational models for each indicator by addressing the correlation among multiple self-propelled hard-hose traveler indicators. The parameter configuration included the sprinkler model, nozzle diameter, rotation angle, and adjacent path spacing. The comprehensive evaluation system encompassed the average application depth, uniformity of water distribution ( CU value), total energy consumption, and irrigation capacity. The average application depth was positively correlated with total energy consumption and negatively correlated with the CU value and irrigation capacity. The strongest correlation was observed between the average water application rate and the irrigation capacity. Two principal components with eigenvalues of 2.046 and 1.023 were selected, accounting for a cumulative contribution rate of 76.735%. The first principal component was primarily determined by the average application depth and irrigation capacity. In contrast, the second principal component was mainly influenced by the CU value and total energy consumption. The optimal parameter configuration scheme is determined based on the comprehensive scores, ranking, and test validation as a dual-sprinkler arrangement (30PY ₂ impact sprinkler) with a nozzle diameter of 10.5 × 5.0 mm, a sprinkler rotation angle of α = 0°, β = 90°, γ = 90°, and an adjacent path spacing of 1.5 R. The study provides guidance for the operation and management of self-propelled hard hose traveler in the field.

Splitter-blade impellers are increasingly being adopted in centrifugal pumps due to their superior performance. However, their service life is significantly reduced when handling fluids containing even small amounts of sediment. To investigate the wear characteristics of splitter-blade centrifugal pumps under solid-liquid two-phase flow conditions, a combined approach of numerical simulation and experimental study was employed to analyze wall wear under low solid-phase particle concentrations. The results demonstrate that the numerical simulations meet the required accuracy for analysis, with maximum relative errors of 4.8% for head and 3.4% for efficiency. The head curve of the centrifugal pump equipped with splitter blades is generally higher than that of the pump without splitter blades under both single-phase and solid-liquid two-phase flow conditions. Notably, under low-flow-rate conditions in the solid-liquid two-phase flow, the impeller with splitter blades demonstrates better head stability. Although the introduction of splitter blades alters the flow field structure at the impeller inlet to some extent, it also enhances the uniformity of pressure and velocity distribution in the circumferential direction at the impeller outlet. The presence of splitter blades primarily affects the wear characteristics on the pressure side of the blades and the middle and rear regions of the impeller rear shroud, resulting in reduced wear. However, as the solid particle concentration increases, impeller wear becomes more severe, suggesting that this type of centrifugal pump should be avoided in high-concentration conditions. Therefore, impellers with splitter blades exhibit certain advantages in transporting fluids with low solid-phase concentrations. This study provides important theoretical insights and data support for the hydraulic optimization of centrifugal pump structures.

This paper investigates research on the dynamic mechanical and energy consumption models during the polyethylene tube retrieval for a self-propelled hard hose traveler. Moreover, the drive parameter design methodology of a traveler is refined to address the irrigation challenges faced by existing sprinklers in sloping fields and fragmented farmland. First, the sprinkler’s electric-drive carrier parameters are designed based on established mechanical theory models of the polyethylene tube deployment. The carrier employs two planetary reduction gearboxes with a transmission ratio of 40 and six batteries with a voltage of 12 V and a capacity of 200 A h. Secondly, the dynamic changes in tensile force and energy consumption are studied by establishing mechanical and energy consumption models for retrieving polyethylene tubes. Then, the drive parameters for the reel truck are designed. The tensile force required for its rotation increases because the polyethylene tube winds longer onto the reel. Moreover, the tensile force and total energy consumption required for retrieving the polyethylene tube decrease. The force required for reel no-load rotation is 49.98 N. When the friction coefficient between the polyethylene tube and soil is 1.0, the tensile force and energy consumption required for sliding are maximized, to 2356.70 N and 52.06 × 10 ⁻³ kW h, respectively. The reel truck selects a reduction gearbox with a transmission ratio of 25 and an efficiency of 85%, along with a three-phase asynchronous motor with a power of 750 W, a speed of 1400 r min ⁻¹ , and a voltage of 220 V. This research will enable in-depth analysis of mechanical and energy consumption characteristics across different operational stages of the polyethylene tube, facilitate structural optimization, and provide technical support for irrigation in sloped and fragmented farmlands.

In this study, a self-propelled hard hose traveler is developed as a modification of the conventional design. The traveler demonstrated enhanced field applicability and intelligence level in Europe and central–eastern China. A parametric configuration scheme was attained through the irrigator’s computational modeling and experimental validation. This study proposed a uniform water distribution calculation model for single-sprinkler linear-move irrigation. The deviation rate between calculated and experimental values was 7.3%. The average application depth decreased with increased sprinkler motion speed and path spacing. The uniformity of water distribution (CU value) exhibited an oscillating trend as the path spacing changed. As the sprinkler rotation angle increased along a specific path, the CU value first rose from 69.2% to 80.0% and then declined to 68.7%. When irrigation and sprinkler motions were combined, the CU value at 1.5 R initially decreased from 92.1% to 72.9%, then increased to 84.2% as the sprinkler rotation angle increased. The combined sprinkler and irrigation motions showed a significantly better uniformity than the specific path irrigation. The highest CU value was 95.0%, with a nozzle diameter of 16.0 × 6.0 mm, a sprinkler rotation angle of 180°, and a path spacing of 1.6 R. This study introduces a novel approach for water-saving irrigation equipment and offers practical guidance for farmers on operating the self-propelled hard hose traveler.

In this study, a self-propelled hard hose traveler is designed based on the traditional hard hose traveler. The traveler demonstrated enhanced field applicability and intelligence level in Europe and central-eastern China. A parametric configuration scheme was attained through the irrigator’s computational modeling and experimental validation. This study proposed a uniform water distribution calculation model for single-sprinkler linear-move irrigation. The deviation rate between calculated and experimental values was 7.3%. The average application depth decreased with increased sprinkler motion speed and path spacing. The uniformity of water distribution (CU value) exhibited an oscillating trend as the path spacing varied. When moving along a specific path, the CU value increased and decreased with the increased sprinkler rotation angle. By combining irrigation and sprinkler motions, the CU value decreased and increased with the increased sprinkler rotation angle. The combined sprinkler and irrigation motions showed a significantly better effect than the specific path irrigation. The highest CU value was 95.0%, with a nozzle diameter of 16.0×6.0 mm2, a sprinkler rotation angle of 180°, and a path spacing of 1.6 R.

This paper introduces the development of a self-propelled hard hose traveler to accelerate the transition of the traditional JP50-180 hard hose traveler toward becoming an irrigation robot and enhancing its applicability in farmland. The uniformity model of linear motion water distribution is established by utilizing the total frequency of application during the sprinkler motion and the radial application depth once during the fixed sprinkler rotation. The average application depth deviation between the tested and calculated values is 7.4%. The effect of combined irrigation with sprinkler motion is superior to that of motion irrigation with a single sprinkler. The average application depth decreases as the motion speed increases while the water distribution uniformity ( CU value) remains constant. The average application depth decreases as the path spacing increases. In contrast, the CU value first increases and then decreases. The highest CU value is approximately 94%, with the optimal path spacing being 1.5R and the optimal combinations of sprinkler rotation angles α, β, and γ being 0°, 90°, and 90°, or 90°, 90°, and, 0°, or 0°, 180°, and 0°, respectively depending on the case. The above indicators are significant for planning the irrigation application of a self-propelled hard hose traveler.

An impact sprinkler loaded on a remote control trailer can be used for motion to improve the efficiency of a single Hard Hose Traveler in small and medium-sized irregular fields. Herein, a model for calculating the combination uniformity coefficient (CU) was established in the square test area under two-directional motion. The accuracy of the irrigation uniformity model was verified using the test data of application depth ( h_n). The results revealed that the nozzle diameter, speed of sprinkler motion ( v), and motion methods can significantly impact the average application depth ([ ]) and the CU value of sprinkler irrigation performance. The motion methods included uniform motion and a constant speed combination motion. The highest CU values were recorded when the primary and secondary nozzle diameters were 10.5 and 4.5 mm, respectively (overall value, about 81.7%). The CU value gradually decreased with the increasing v value of the sprinkler. The CU value was higher under the constant speed combination motion than the uniform motion. The [ ] value gradually decreased with increasing v value. The [ ] value was classified based on the water requirement of different crops. The optimal CU value corresponding to each grade of the [ ] value was obtained in different schemes of the combination of sprinkler speeds. This research guides the realization of variable spraying of a Hard Hose Traveler and the intelligent uniform motion of the sprinklers.