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CN 61-1069/T
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2026年第60卷第10期
Special Topic Fusion Perception and Decision-Making Planning for Intelligent Driving
摘要：Based on intelligent connected vehicles and vehicle-road-cloud cooperative networks, the perception blind spots of single-vehicle intelligence in long-tail scenarios, such as occlusion and long-range detection, are effectively compensated by cooperative perception technology through information interaction among multiple agents. However, the large-scale deployment of such systems is critically bottlenecked by limited wireless communication bandwidth and multi-source heterogeneous data. To address this issue, communication-efficient transmission methods for cooperative perception in autonomous driving are systematically reviewed. First, feature filtering mechanisms for suppressing redundant background transmission are summarized at both the spatial region and instance task levels. Second, representative methods for addressing node heterogeneity, temporal asynchrony, and spatial misalignment are summarized, focusing on key issues in multimodal information fusion, including interaction topology construction, spatiotemporal pose alignment, and cross-modal semantic alignment. Then, implementation approaches that balance communication efficiency and perception accuracy under bandwidth constraints are reviewed along three pathways: sparse representation for feature compression, generative completion, and semantic collaboration with large models. Finally, large-scale open-source datasets in this field are systematically compiled, and current bottlenecks and future development trends in scene cognition, dynamic network security, and the credibility of generative reconstruction are deeply analyzed. Through this paper, relevant research progress is systematically reviewed, and a theoretical reference is provided for the construction of more robust and secure intelligent connected vehicle-road cooperative networks.关键词：Autonomous Driving;Cooperative Perception;Intelligent Connected Vehicles;Multimodal Information Fusion;communication efficiency163|184|0更新时间：2026-09-29- 摘要：To address the issues of false positives and false negatives caused by insufficient confidence calibration and single post-processing decision mechanisms in real-time object detection models, a confidence-stratified collaborative decision-making framework is proposed. Using the YOLOv5model as the base detection network, the framework constructs a confidence stratification mechanism during the inference stage. Based on the predicted confidence distribution, candidate bounding boxes are divided into a high-confidence passthrough path and a low-confidence refined discrimination path. Meanwhile, an extreme gradient boosting (XGBoost) model is introduced to perform secondary classification and confidence recalibration on low-confidence samples, achieving differentiated processing of detection results and optimized allocation of computational resources. In the fusion stage, a unified decision integration module is designed to perform structured fusion and filtering on the outputs from different paths. This improves overall detection performance and predictive reliability without altering the backbone network structure or significantly increasing computational complexity. Experimental results show that, validated on the COCO dataset in a 2080Ti testing environment, the mean average precisionmAP, 50-95 of the improved YOLOv5s and YOLOv5m models increased by 1.98% and 1.99%, respectively. When generalized to YOLOv8m, the model achieved anmAP, 50-95 of 55.07% with an inference speed of 165.4frame/s. This method establishes a novel fusion paradigm for collaborative decision-making between deep neural networks and traditional machine learning models, providing a technical pathway that balances accuracy, efficiency, and credibility for object recognition systems in high-reliability domains.关键词：object detection;Extreme Gradient Boosting;YOLOv5model;confidence stratification;machine learning56|53|0更新时间：2026-09-29
- 摘要：An adaptive multi-scale three-dimensional point cloud registration network for autonomous driving is proposed to address the issues of sparse light detection and ranging point clouds, ambiguous features, and keypoint mismatches caused by low overlap in autonomous driving scenarios. First, multi-level features of sampled points are extracted via an adaptive multi-scale feature extraction module, and precise keypoint localization is achieved by incorporating an adaptive neighborhood stabilizer, thereby resolving the matching difficulties caused by feature ambiguity. Second, the inlier confidence of the point pairs to be registered is enhanced by integrating multi-scale feature matching consistency with geometric consistency verification. Finally, based on this confidence, a coarse-to-fine iterative optimization strategy is adopted to accomplish accurate three-dimensional point cloud registration. Test results on the KITTI dataset indicate that a relative translation error as low as 0.0618mand a relative rotation error as low as 0.21° are achieved by the network, with a registration recall of up to 99.8%. Furthermore, test results on the nuScenes dataset show that registration recalls of 90.1%, 83.3%, and 78.8% are achieved at inter-frame distances of 10, 20, and 30m, respectively. It is validated by the aforementioned results that mismatches in complex road scenarios are effectively suppressed by the proposed network, and high-precision, highly robust large-scale three-dimensional point cloud registration is realized. The practical application requirements under dynamic and complex traffic conditions are met by this research, and reliable technical support is provided for precise localization and environmental perception in autonomous driving scenarios.关键词：intelligent driving;three-dimensional point cloud registration;adaptive;multi-scale features94|143|0更新时间：2026-09-29
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Robust Guaranteed Performance Fault-Tolerant Control of Steer-by-Wire System for Intelligent Vehicle
摘要：The steer-by-wire (SBW) system is a key technology for intelligent vehicles to achieve high-level intelligent driving. However, its tracking accuracy and control performance are difficult to guarantee under multiple uncertainties and input constraints. To address this issue, a cooperative fault-tolerant control method integrating robust guaranteed performance control and feedforward regulation is proposed. First, an SBW simulation model incorporating system parameter perturbations, external disturbances, actuator faults, and input constraints is established. Then, multiple uncertainties and faults within a certain range are unified into the control design framework. By constructing a quadratic performance index and solving the guaranteed performance control law via linear matrix inequalities, the tracking performance and robustness of the system are constrained, and the closed-loop stability is proved via the Lyapunov criterion. Furthermore, a piecewise variable-curvature feedforward regulator is integrated to improve the initial response speed, forming a complete steering angle tracking controller. Simulation and real-vehicle test results show that the proposed method achieves accurate and stable tracking with fast regulation capability. Under typical conditions, the comprehensive simulation front-wheel angle tracking error is reduced by about 50% compared with the standalone guaranteed performance control, 65% compared with PID control, and 63% compared with adaptive sliding mode control. The experimental error is reduced by about 17% compared with the standalone guaranteed performance control and 4% compared with PID control. The proposed method can ensure the efficient and stable operation of SBW vehicles in varying scenarios and fault conditions.关键词：steer-by-wire;fault-tolerant control;guaranteed performance control;multiple uncertainties;input constraints;intelligent vehicle35|41|0更新时间：2026-09-29 Special Topic Embodied Intelligent Robot
摘要：To address the issues of environmental comfort degradation and positioning interference caused by electromagnetic vibration and noise in wheel direct-drive motors of mobile robots during operation, a collaborative optimization strategy based on an improved multi-objective mayfly algorithm (IMOMA) and a parameter scanning method (PSM) was proposed. Taking an outer-rotor permanent magnet synchronous wheel direct-drive motor with an outer diameter of 355.6mm as the research object, the engineering application value of this strategy was verified through the multi-objective structural optimization design of auxiliary stator slots and a step-skewed rotor. By introducing a dual-layer roulette wheel selection and dynamic dimension transformation mechanism, the global search capability and the uniformity ofPareto front coverage of the IMOMA algorithm were enhanced. The approach combined with a PSM-constructed multi-objective performance database for auxiliary slot parameters (width, depth, rotation angle) and step-skewing parameters achieved efficient collaborative optimization. The effectiveness of the optimized solution was verified through a multi-physics coupled simulation model. The results show that the optimized motor exhibits the following: the average housing end-cap vibration acceleration was reduced by 39.35mm/s2 at 600r/min and 41.78mm/s2 at 1200r/min; the equivalent radiated power was reduced by 9.2dB at the stator-housing interface and by 9.0dB at a distance of 1min the air domain; and noise propagation uniformity was significantly improved, with a 3.913dB reduction in A-weighted sound pressure level at 1200r/min. This effectively lowered the noise level from the 70dB range to the 60dB range, mitigating noise harshness and enhancing motor comfort. This study provides a theoretical basis for the low-noise design of direct-drive motors.关键词：mobile robots;wheel direct-drive motor;electromagnetic vibration;improved multiobjective mayfly algorithm;noise level43|31|0更新时间：2026-09-29- 摘要：To meet the demands of humanoid robot joints for actuators with high load capacity, high precision, and compact integration, and to address the difficulty in predicting the meshing position and axial clearance of a novel inverted recirculating planetary roller screw mechanism (IRPRSM) under machining errors, this study establishes unified three-body helical surface equations and a spatial meshing model for the IRPRSM. Consequently, the influence mechanism of machining errors on key positional accuracy parameters—such as the actual meshing position, meshing radius, deflection angle, and axial clearance—is revealed. Results show that eccentricity error causes periodic fluctuations in the meshing radius and axial clearance during mechanism operation, with the fluctuation frequency increasing with the number of screw starts. Within an error range of ±0.03mm, the difference in axial clearance induced by the pitch diameter errors of the screw and roller does not exceed 2μm. When a flank angle error is present solely in the screw or the roller, the axial clearance peaks at 24.58μm at 0° and drops to approximately 10-12μm as the error increases to ±3°. When the flank angle errors of the screw and roller change equally in the same direction, the axial clearance increases only from 22.87μm to 26.11μm, indicating that synchronous error variation has a relatively minor effect on the clearance. Although the thread indexing error does not alter the axial contact position, it causes a redistribution of the clearance between the upper and lower helical surfaces. This study provides a theoretical basis for the manufacturing and high-precision assembly of IRPRSMs in linear actuators for humanoid robot joints.关键词：humanoid robot;joint;planetary roller screw mechanism;meshing characteristics;machining error115|276|0更新时间：2026-09-29
- 摘要：To address the degradation of current control performance caused by time delay and parameter mismatch in digitally controlled permanent magnet synchronous motor (PMSM) systems, a novel adaptive predictive current control method is proposed based on the conventional deadbeat predictive current control. By incorporating a forgetting-factor recursive least squares algorithm and an improved model adaptive compensation structure, the coupled effects of system delay and severe parameter mismatch on current control are effectively eliminated. The research results indicate that the proposed method exhibits faster dynamic response and higher steady-state accuracy under various parameter mismatch conditions. With theq-axis as an example, the average dynamic current adjustment time is only 12.0ms, and the maximum root mean square error of current tracking is below 15.4mA. Compared with the conventional proportional-integral control, the dynamic current adjustment time is significantly reduced by approximately 12.4ms, and the maximum root mean square error of current tracking is substantially decreased by 58.6%. Furthermore, the execution time of the proposed method is approximately 19.93-21.20μs. The required computational load is well within the capacity of existing digital signal processors, thereby fully guaranteeing real-time computation. The impacts of time delay and parameter control effectively mitigated by study, and the tracking performance of the current loop is significantly improved, providing a practical and effective solution for further implementing high-performance PMSM drive control.关键词：delay compensation;parameter mismatch;adaptive predictive current control;forgettingfactor least-squares algorithm39|154|0更新时间：2026-09-29
Special Topic Intelligent Perception and Autonomous Decision-Making
摘要：To address the issues of low roadway cutting and profiling efficiency and high reliance on manual operation in traditional roadheader control methods, an event-state-driven virtual-real interactive predictive control method for intelligent tunneling equipment is proposed. First, an event-state model of the roadheader is constructed to discretize the cutting trajectory into key state nodes. The cutting state is monitored in real time to identify abnormal body offsets caused by hard rock. An event-driven virtual-real state evolution logic is designed to achieve state transition and synchronization between the physical entity and its digital twin. Second, a digital twin model of the roadheader is constructed to achieve virtual mapping of the cutting process. Based on model predictive control (MPC), the actual trajectory is predicted to provide virtual decision-making for virtual-real state alignment and abnormal trajectory correction. Through virtual-real interaction between the digital twin and the physical entity, a closed loop from state perception to decision execution is realized. Finally, a virtual-real interaction experimental platform for the roadheader is built for experimental verification. Algorithms are utilized to identify abnormal body offsets, and trajectory correction is achieved based on MPC coupling control decisions. The results show that the MPC-based coupling control reduces the maximum trajectory tracking error from 18.5mm to 7.2mm, corresponding to a reduction of 61.1% in the maximum deviation. This research method can provide effective technical support for the intelligent control of coal mine roadway tunneling equipment.关键词：intelligent tunneling;digital twin;virtual-real state alignment;virtual-real interaction;model predictive control37|39|0更新时间：2026-09-29- 摘要：To address the challenges posed by aviation operational data in the context of the low-altitude economy—characterized by numerous discrete attributes and high heterogeneity—as well as the inherent limitations of theK-modes clustering algorithm, including sensitivity to initial cluster centers, susceptibility to local optima, and insufficient adaptability to complex data, this paper proposes aK-modes clustering algorithm optimized by the quantum collaborative artificial lemming algorithm (QCALA). The QCALA-K-modes algorithm is constructed by introducing quantum tunneling initialization into the cluster center generation process and designing four strategies: adaptive step-size perturbation, multi-burrow collaborative excavation, quantum chaotic spiral foraging, and tri-mode switching escape. These strategies achieve synergistic optimization of global exploration and local exploitation under the regulation of an energy factor. The proposed method is validated using 8standard benchmark functions, 6public datasets, and 539383flight records from the Heywhale community. On the public datasets, QCALA-K-modes achieves a normalized mutual information (NMI) of 0.9062on the Aggregation dataset, outperformingK-means (0.8395) and hierarchical clustering (0.9010); on the Bupa dataset, its NMI reaches 0.1384, surpassingK-means (0.0009) and hierarchical clustering (0.0001); and on the Records dataset, the NMI is 0.5319. For the flight data, the inter-cluster range of delay rates among the four flight patterns reaches 35.44%, effectively distinguishing between high-and low-risk operational modes and validating the clustering discriminability and business interpretability of the proposed algorithm. The proposed algorithm provides methodological support for the refined identification of aviation operational statuses and the tiered management of delay risks in low-altitude economy scenarios.关键词：Quantum collaborative artificial lemming algorithm;K-modes clustering;aviation data;low-altitude economy37|15|0更新时间：2026-09-29
- 摘要：To ensure the safety of train operations under complex weather conditions, and to address the issues of existing object detection algorithms for foreign object intrusion on railway tracks, such as a large number of parameters, poor image clarity, high rates of false and missed detections, and slow inference speed, a foreign object intrusion detection algorithm for railway tracks under complex weather conditions (RCW-YOLO) based on the improved YOLOv11n is proposed. First, based on the YOLOv11n algorithm, a rain-fog perception dynamic fusion gating mechanism is introduced, and a rain-fog density estimator module is designed. Second, a rain-fog attention branch is added to the object detection head framework DynamicHead, and a rain-fog density coefficient is integrated into the convolutional offset to reduce the false and missed detection rates. Third, in the backbone and neck networks, an attention-enhanced multi-subband fusion wavelet pooling module is utilized to replace the existing convolutional modules of YOLOv11n, which reduces the number of parameters and improves inference speed while maintaining detection performance. Finally, a newly designed loss function, EW-MPDIoU, is introduced to replace the original CIoU loss function, thereby improving detection accuracy. Experimental results show that the proposed RCW-YOLO algorithm achieves an average detection accuracy of 84.6%, which is 9.2% higher than that of the YOLOv11n algorithm, while the number of parameters is reduced by 18.15%. Compared with the mainstream object detection algorithms YOLOv9t and YOLOv10n, the average detection accuracy of the RCW-YOLO algorithm is improved by 11.3% and 11.3%, respectively, and the number of parameters is reduced by 21.63% and 25.34%, respectively. Furthermore, compared with the latest YOLOv12and YOLOv13algorithms, the average detection accuracy is improved by 7.8% and 7.0%, respectively, and the number of parameters is reduced by 22.18% and 19.93%, respectively.关键词：Railway tracks;Foreign object intrusion;Complex weather;object detection59|152|0更新时间：2026-09-29
Special Topic Thermal Management of Electric Vehicles
摘要：To address the issues of large fluctuations in the thermal load of power batteries, stringent requirements for temperature control response, and the inability of existing evaluation methods to simultaneously reflect system energy efficiency and irreversible losses under high-rate fast-charging and dynamic driving conditions for electric vehicles, this study proposes a comprehensive evaluation method for the operating performance and exergy efficiency of integrated thermal management systems. On this basis, a thermodynamic analysis model is developed that considers temperature control response, system energy efficiency, and component irreversible exergy destruction. Furthermore, a multi-mode integrated thermal management test bench compatible with both battery direct cooling and liquid cooling architectures is constructed, enabling the switching and comparison of the two architectures and different modes under unified boundary conditions. Based on the established comprehensive evaluation method, the temperature control characteristics, energy efficiency performance, and thermodynamic loss patterns of the two architectures are comparatively studied under the dynamic driving condition of the China light-duty vehicle test cycle for passenger cars (CLTC-P) and fast-charging conditions ranging from 0.5C to 3C. The results indicate that under dynamic driving conditions, the liquid cooling architecture provides better cabin comfort and system stability due to its large heat capacity. Meanwhile, the direct cooling architecture maintains a coefficient of performance (COP) above 2.5in the mid-to-late stages, achieving higher steady-state energy efficiency. Under high-rate fast-charging conditions at 1C and above, the direct cooling architecture eliminates the secondary heat transfer resistance, resulting in a significantly faster cooling response than that of the liquid cooling architecture. However, influenced by the phase-change flow regime of the refrigerant, the maximum steady-state temperature difference within its battery module reaches 7.8℃, indicating poorer local temperature uniformity compared to the 4.7℃ observed in the liquid cooling architecture. The direct cooling architecture effectively reduces irreversible heat transfer losses; its battery cold plate achieves an exergy efficiency of 47%, which is significantly higher than the 29% of the battery chiller in the liquid cooling loop. Furthermore, during long-term dynamic operation, the transient total exergy efficiency of the direct cooling architecture reaches up to 20%. This demonstrates that the direct cooling architecture generally exhibits greater advantages in terms of response speed, system energy efficiency, and degree of thermodynamic perfection. The established evaluation method can effectively identify the performance differences between different architectures under dynamic and high-load conditions, providing methodological support and an experimental basis for architecture selection and control optimization of integrated thermal management systems for electric vehicles.关键词：electric vehicles;integrated thermal management;direct and liquid cooling;thermodynamic characteristics83|413|0更新时间：2026-09-29- 摘要：To address the issues of uneven heat dissipation and high flow channel resistance in traditional liquid cooling plates, as well as the stringent requirements for coolants and the risk of battery short circuits in full-immersion cooling, this study proposes a novel staggered semiimmersed liquid cooling plate structure. Using numerical simulations combined with the NTGK electrochemical model and the governing equations for fluid flow and heat transfer, the effects of inlet velocity, channel angle, and channel spacing ratio (the ratio of channel spacing to channel width) on the heat dissipation performance were systematically analyzed. The reliability of the model was verified through single-cell heat generation experiments and a grid independence analysis. The results indicate that increasing the inlet velocity significantly enhances the heat dissipation performance of the liquid cooling plate and reduces the maximum temperature of the battery module. Compared with the operating condition at an inlet velocity of 1.50m/s, an inlet velocity of 2.25m/s improves the comprehensive heat dissipation performance of the liquid cooling plate by 204.21% and reduces the maximum temperature of the battery module by 0.27K. When the channel angle is 45°, the comprehensive heat dissipation performance of the liquid cooling plate is optimal, and its comprehensive heat dissipation capacity is increased by 114.40% compared to that at a channel angle of 17°. When the channel width is 5mm, the liquid cooling plate with a channel spacing ratio of 5∶5exhibits better comprehensive heat dissipation performance. Furthermore, compared with the conventional plate structure, the proposed semi-immersed structure improves the comprehensive heat dissipation performance by 24.00% and reduces the maximum temperature of the battery module by 2.86K. This study provides a theoretical basis and technical reference for the design of battery heat dissipation structures.关键词：semi-immersed;staggered;liquid cooling plate;lithium battery;heat dissipation performance27|32|0更新时间：2026-09-29
Special Topic Thermal-Fluid Analysis and System Optimization
摘要：To reveal the mechanism by which internal axial heat transfer within the rotor affects the aerodynamic performance of rotating components in ultra-micro gas turbines, and to evaluate the restorative effect of an internal cooling structure on rotor performance, numerical simulations of flow and heat transfer in a 350Wultra-micro gas turbine rotor were conducted using a conjugate heat transfer approach. The effects of internal heat transfer and internal shaft cooling on component performance were comparatively analyzed. The results indicate that internal heat transfer reduced the pressure ratio of the centrifugal compressor by 5.71% and its efficiency by 5.17%, and decreased the output power of the radial inflow turbine by 10.96% and its efficiency by 2.48%. However, heat transfer also stabilized the internal flow structures within the compressor and turbine to a certain extent, thereby reducing flow losses. Following the implementation of the internal cooling structure, the pressure ratio and efficiency of the compressor increased by 1.13% and 0.98%, respectively, while the output power and efficiency of the turbine increased by 2.90% and 0.10%, respectively. Furthermore, the temperature of the cantilever shaft was reduced by 45.10%. Based on the flow-stabilizing effect induced by heat transfer, a design approach of appropriately adopting higher blade loading is proposed to compensate for the degradation in work output caused by heat transfer. The internal cooling structure effectively reduces the cantilever shaft temperature and improves the bearing operating environment, thereby providing an effective thermal protection scheme for the long-term stable operation of ultra-micro gas turbines under compact conditions.关键词：ultra-micro gas turbine;centrifugal compressor;radial inflow turbine;conjugate heat transfer;numerical simulation45|134|0更新时间：2026-09-29- 摘要：To investigate the combustor-turbine interactions and to deepen understanding of the formation mechanism as well as the influencing factors of non-uniform aerothermal characteristics at a turbine inlet, a non-reacting sector combustor simulator was constructed. This facility was capable of reproducing and regulating coupled non-uniform characteristics at turbine inlets, including hot streaks, swirling flow, total pressure gradients, and high turbulence intensity. The combustor flow split was decoupled into two key parameters: the mainstream swirling flow rate and the inner-to-outer liner coolant flow ratio. A traverse system was employed to scan the thermal-flow field at the turbine inlet plane using a seven-hole probe equipped with a thermocouple under five operating conditions, revealing the influence mechanisms of combustor flow splits on non-uniform characteristics. The results indicate that the non-uniform characteristics at the turbine inlet are mainly due to the thermal-fluid coupling between the combustor's swirling flow and the effusion cooling flow. An increase in the mainstream swirl flow rate enhances the dynamic effect of the swirl and expands its influence area. Specifically, a 20% increase in the mainstream swirl flow rate causes the variation ranges of the circumferentially averaged swirl and pitch angles to be expanded by 28.3% and to be reduced by 33.5%, respectively. Altering the inner-to-outer coolant flow ratio causes a radial shift of the swirling core by approximately 10% of the passage height and significantly changes the pressure and temperature gradients on the coolant side. These findings provide critical aerothermal boundary conditions for aerodynamic and cooling design of high-pressure turbines in next-generation aero-engines, and offer valuable insights for integrated combustor-turbine design.关键词：non-uniform aerothermal characteristics at turbine inlet;combustor-turbine interaction;combustor flow split;hot streaks;swirling flow25|34|0更新时间：2026-09-29
- 摘要：To achieve continuous and efficient ortho-para hydrogen conversion during the hydrogen liquefaction process, the flow resistance, heat transfer performance, and ortho-para hydrogen catalytic conversion characteristics of a catalyst-filled plate-fin heat exchanger (CFPFHE) were systematically investigated using a combined experimental and numerical approach. Based on the established cryogenic experimental test platform for the CFPFHE, experiments on flow, heat transfer, and ortho-para hydrogen conversion were conducted under well-insulated conditions at various Reynolds numbers. Furthermore, the para-hydrogen volume fraction at the outlet of the packed channel (hot side) was calculated using the heat balance method. Additionally, a three-dimensional numerical model of the CFPFHE was established to simulate the flow, heat transfer, and ortho-para hydrogen conversion processes, and the model was validated by the experimental results. The results indicate that with an increase in the Reynolds number, the friction factors on both the hot and cold sides decrease gradually; the heat transfer factor on the hot side increases first and then decreases, reaching a peak at a hot-side Reynolds number of approximately 213, while the heat transfer factor on the cold side decreases monotonically with the cold-side Reynolds number; and the outlet para-hydrogen volume fraction increases first and then decreases slightly with an increase in the hot-side Reynolds number. The numerical simulation results are found to be in good agreement with the experimental data, and the average relative deviations of the friction factor, heat transfer factor, and outlet para-hydrogen volume fraction are all less than 7.15%. The reliability of the established numerical model is verified by the research results, and a reference is provided for the engineering application of the CFPFHE in large-scale hydrogen liquefaction plants.关键词：ortho-para hydrogen catalytic conversion;plate-fin heat exchanger;filled channel;flow and heat transfer;numerical simulation47|143|0更新时间：2026-09-29
- 摘要：To address the issues of high superheat of regenerative extraction steam, large irreversible losses, and limited improvement in energy efficiency in double reheat units, this study selects a 660MW ultra-supercritical double reheat unit as the research object to conduct configuration optimization design and thermal performance analysis of the regenerative system. Utilizing the Ebsilon thermal simulation platform, five optimization schemes are designed from the aspects of system configuration adjustment, coupling a back pressure extraction steam turbine (BEST), regenerative stage allocation, and reheat parameter matching. A comparative analysis of the thermal performance of each scheme is conducted under rated conditions, and full-range operating condition performance research and parameter optimization are carried out for the optimal scheme. Combined with the graphical exergy analysis method, the mechanism by which BEST reduces irreversible losses and achieves efficient cascade utilization of extraction steam energy through “doing work first and then releasing heat”is elucidated. The results show that the optimized configuration with a 12-stage regenerative system and a 6-stage BEST exhibits the best comprehensive performance. Compared with the original configuration, the turbine heat rate decreases by 53.57kJ·kW-1·h-1, the standard coal consumption rate is reduced by 1.93g·kW-1·h-1, and the exergy efficiency of the turbine system increases by 0.79%, demonstrating energy-saving potential under all operating conditions. After optimizing the reheat parameters, the system heat rate is further reduced by 4.23kJ·kW-1·h-1, and the turbine thermal efficiency reaches 51.14%, which is 0.42% higher than that of the original configuration. The research results can provide theoretical support for the energy conservation of double reheat coal-fired power units and the engineering application of BEST technology.关键词：ultra-supercritical double reheat unit;superheat degree;back pressure extraction steam turbine;regenerative stage;configuration optimization31|58|0更新时间：2026-09-29
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摘要：To improve the aerodynamic performance of a U-shaped impulse turbine, a collaborative multi-objective optimization study on the flow passage and blades was conducted. First, the rotor blades of the impulse turbine were parametrically modeled, and the rotor blade profile and flow passage width were selected as design variables. Second, optimal Latin hypercube sampling was employed to generate a sample set in the high-dimensional decision space and obtain the sample response values, based on which a Kriging surrogate model was constructed. Third, with turbine efficiency and output power as the optimization objectives, the non-dominated sorting genetic algorithm Ⅱ (NSGA-Ⅱ) was utilized for global optimization to obtain the Pareto solution set. Then, the technique for order preference by similarity to an ideal solution (TOPSIS) method was adopted to select the geometric parameter combination with the best comprehensive performance from the solution set, yielding the optimized turbine model. Finally, numerical investigations were conducted on the internal flow characteristics of the optimized and original designs. Combined with global sensitivity analysis, the influence mechanisms of key geometric parameters on performance were clarified. The results indicate that the geometric angle of the rotor blade camber line is the key parameter affecting efficiency, while the heights of the guide vanes and rotor blades are the main factors influencing output power. The efficiency and output power of the optimized impulse turbine are increased by 3.35% and 3.13%, respectively. Moreover, the optimized design effectively suppresses flow separation on the rotor suction surface and reduces overshot losses in the downstream guide vane region, thereby improving internal flow stability and enhancing energy conversion efficiency. These results provide a theoretical reference for the collaborative design of flow passages and blades in impulse turbines.关键词：impulse turbine;U-shaped flow passage;multi-objective optimization;aerodynamic performance;global sensitivity analysis27|31|0更新时间：2026-09-29- 摘要：To address the issue that structural discontinuities within the micro-clearance of spiral-grooved liquid self-lubricating bearings readily induce cavitation and consequently affect the flow characteristics of the self-lubricating fluid, a visualized experimental system for the cavitating flow of a cryogenic thermosensitive medium in a sudden expansion micro-clearance was established to reveal the influence mechanism of the sudden expansion structure on cryogenic cavitating flow. Through experimental investigations, the effects of back pressure, inlet pressure, and clearance height on the morphological evolution and temperature and pressure characteristics of liquid nitrogen cavitation in the sudden expansion micro-clearance were analyzed. The results indicate that the cavitation effect is enhanced by a decrease in dimensionless back pressure, an increase in dimensionless inlet pressure, and a reduction in dimensionless clearance height. Specifically, when the dimensionless back pressure is reduced from 0.758to 0.694, the cavitation area, pressure drop, and temperature drop in the cavitation area are increased by 39%, 14%, and 17%, respectively. When the dimensionless inlet pressure is increased from 1.048to 1.371, the cavitation area, pressure drop, and temperature drop are increased by 135%, 77%, and 61%, respectively. Furthermore, when the dimensionless clearance height is decreased from 3.0to 1.8, the pressure drop and temperature drop in the cavitation area are increased by 96% and 22%, respectively. Additionally, the pressure drop, temperature drop, and cavitation length are decreased with an increase in the inlet cavitation number. A theoretical basis for the optimal design of cryogenic fluid self-lubricating hydrodynamic bearings is provided by the cavitating flow laws in the sudden expansion micro-clearance obtained in this study.关键词：liquid nitrogen;cavitating flow;hydrodynamic bearing;sudden expansion micro-clearance27|43|0更新时间：2026-09-29
- 摘要：To address the challenges of low thermal conductivity and liquid leakage in organic solid-liquid phase change materials, combined with the high-value utilization of waste biomass resources, a dual optimization strategy involving the framework structure modification of biochar and interfacial chemical regulation was proposed. Using waste white pine wood as the carbon source, a magnetic and highly thermally conductive biochar support (KFeC) with a hierarchical pore structure was prepared through a stepwise treatment of KOH chemical activation and Fe loading. Using this as the matrix, the biosurfactant rhamnolipid was introduced as an interfacial modifier, and a form-stable KFeC/paraffin/rhamnolipid composite phase change material (KFeC/PWR) was prepared. The effects of the pore structure of the support and interfacial modification on the phase change behavior, thermal conductivity, and thermal cycling stability of the composite materials were systematically investigated. The results demonstrate that through the synergistic effect of KOH activation and Fe-induced local ordering of the carbon skeleton, the pore structure of the biochar was significantly optimized, and the specific surface area of KFeC was increased to 2.03times that of the original biochar. Furthermore, an efficient thermal conduction network was constructed by in-situ generated iron species (Fe0/Fe3O4) nanoparticles, and the thermal conductivity of the composite material was increased to 0.602W·m-1·K-1, which was 2.5times that of pure paraffin. In addition, the interfacial compatibility was significantly improved and the capillary adsorption force was enhanced by rhamnolipid through its anchoring effect at the inorganic-organic interface. After 50melting-freezing cycles, the latent heat loss rate of KFeC/PWR was only 1.95%, which was much lower than 12.25% in the unmodified group, and no macroscopic leakage phenomenon was observed. The effectiveness of the biosurfactant-assisted encapsulation strategy was validated by this study, and a new approach was provided for the design of long-life and highly reliable biomass-based phase change thermal energy storage materials.关键词：biochar;modification;composite phase change materials;thermal energy storage53|160|0更新时间：2026-09-29
- 摘要：To address the issues of traditional analytical methods, such as numerical divergence when handling worm gear modification boundaries, as well as the low efficiency and difficulty in obtaining underlying data in solid simulations, a digital simulation modeling method for worm gear machining with an oversize hob based on the discrete envelope principle is proposed. A kinematic mathematical model for worm gear machining with an oversize hob is constructed. Based on the grid division of the worm gear tooth flank, the tooth flank is generated through the numerical envelope of discrete cutting intersection line families across multiple sections of the worm gear. The validity of the proposed method is verified using VERICUT simulation software, and the influence patterns of the oversize coefficient and the number of worm threads on the tooth flank topography are systematically analyzed. The results show that compared with the classical spatial meshing analytical method, the maximum absolute normal approximation error of the discrete envelope algorithm over the entire tooth flank domain strictly converges to the order of 1μm; the geometric error in the effective working region of the simulation is strictly controlled within 0.001mm, with local residual errors not exceeding 0.01mm. The oversize coefficient dominates the modification magnitude: when the oversize coefficient increases from 1.05to 1.20, the maximum negative deviations at the edges of single- and triple-thread worms increase from -0.03mm and -0.04mm to -0.1184mm and -0.1537mm, respectively. The number of worm threads determines the error distribution pattern; the lead angle effect of multi-thread worms causes asymmetric distortion of the modification at the mesh-in and mesh-out ends. This study provides a three-dimensional geometric foundation for the selection of oversize process parameters, loaded tooth contact analysis of worm gear pairs, and proactive modification design for wear resistance in engineering practice.关键词：worm gear machining;oversize hob;discrete enveloping;digital simulation;tooth flank topological morphology32|42|0更新时间：2026-09-29
- 摘要：To address the inherent contradiction between lightweight design and low-frequency broadband bandgap performance in lightweight metastructures, a synergistic design theory and method for ultra-low-frequency broadband bandgaps in lightweight two-stage inertial amplification metastructures based on the motion decomposition and conversion mechanism are proposed. By coupling a linkage-based inertial amplification mechanism with a screw-type inerter mechanism as the specific physical configuration, a lightweight two-stage inertial amplification resonator with ultra-low-frequency characteristics is constructed and introduced into the metastructure, whereby a synergistic design of lightweight characteristics, ultra-low-frequency performance, and broadband bandgap is achieved. It is revealed by the research results that a large equivalent inertial mass is generated by the two-stage inertial amplification mechanism excited by the dominant mode of the resonator. This substantial mass not only endows the resonator with ultra-low-frequency characteristics but also produces a strong inertial effect and strong modal suppression forces, whereby an ultra-low-frequency broadband bandgap is established within the lightweight metastructure. It is further demonstrated that the bandgap starting frequency of this type of metastructure can be reduced to 6.32Hz, which is decreased by 77.6% compared to a single-stage inertial amplification metastructure with identical parameters, while the relative bandwidth is broadened by a factor of 26.3. The inclination angle of the inclined rod, the geometric parameters of the flywheel, and the screw lead are identified as the key parameters for regulating the inertial amplification factor. Through multi-parameter synergistic design optimization, precise regulation of the target bandgap can be achieved. By enhancing the inertial amplification factor, the inherent contradiction between structural lightweighting and ultra-low-frequency broadband bandgaps is effectively overcome by the synergistic design method for lightweight two-stage inertial amplification metastructures proposed in this paper.关键词：ultra-low-frequency broadband bandgap;metastructure;inertial amplification;lightweighting26|49|0更新时间：2026-09-29
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