摘要：
The inadequate wear durability of CoCrFeNiMo high-entropy alloy coatings poses great challenges to achieving reliable surface protection for engineering components. This study strategically addresses this limitation by incorporating ceramic carbide particles. The pure CoCrFeNiMo (P0), CoCrFeNiMo-10wt%Cr 3 C 2 (CrC10), and CoCrFeNiMo-10wt%B 4 C (BC10) composite coatings were deposited onto Q235 substrate utilizing laser cladding. Those coatings' structural characteristics, mechanical properties, tribological behavior, and wear mechanisms were analyzed and compared. The P0 coating was composed of FCC and σ phases with a herringbone-like hierarchical eutectic structure, showing good fracture toughness (10.7–24.61 MPa·m 1/2 ). The Cr 3 C 2 -added coating had a typical dendrite structure, and the primary phase from FCC gradually transformed upward into the σ phase. Adding B 4 C particles induced plenty of carbides and borides precipitation such as MoC, M 7 C 3 , and Fe 3 (B, C) in BC10 coating. Adding carbide particles promoted the solid solution strengthening of C and B atoms and in-situ precipitation of reinforcement phases, significantly enhancing the hardness. The hardnesses of P0, CrC10, and BC10 coatings were 652.8, 744.3, and 1162.1 HV 0.2 , respectively. Benefiting from the synergistic effect of the Mo-rich hardening phase and lubricating oxide layer, the BC10 coating achieved the lowest wear rate (9.8 × 10 −6 mm 3 ·N −1 ·m −1 ), showing an order-of-magnitude improvement over the P0 and CrC10 coatings. The P0 and CrC10 coatings predominantly exhibited abrasive wear modes. Surprisingly, the worn surface of the BC10 coating was very slight without detectable scratches or delamination, which was dominated by oxidative wear.
The inadequate wear durability of CoCrFeNiMo high-entropy alloy coatings poses great challenges to achieving reliable surface protection for engineering components. This study strategically addresses this limitation by incorporating ceramic carbide particles. The pure CoCrFeNiMo (P0), CoCrFeNiMo-10wt%Cr 3 C 2 (CrC10), and CoCrFeNiMo-10wt%B 4 C (BC10) composite coatings were deposited onto Q235 substrate utilizing laser cladding. Those coatings' structural characteristics, mechanical properties, tribological behavior, and wear mechanisms were analyzed and compared. The P0 coating was composed of FCC and σ phases with a herringbone-like hierarchical eutectic structure, showing good fracture toughness (10.7–24.61 MPa·m 1/2 ). The Cr 3 C 2 -added coating had a typical dendrite structure, and the primary phase from FCC gradually transformed upward into the σ phase. Adding B 4 C particles induced plenty of carbides and borides precipitation such as MoC, M 7 C 3 , and Fe 3 (B, C) in BC10 coating. Adding carbide particles promoted the solid solution strengthening of C and B atoms and in-situ precipitation of reinforcement phases, significantly enhancing the hardness. The hardnesses of P0, CrC10, and BC10 coatings were 652.8, 744.3, and 1162.1 HV 0.2 , respectively. Benefiting from the synergistic effect of the Mo-rich hardening phase and lubricating oxide layer, the BC10 coating achieved the lowest wear rate (9.8 × 10 −6 mm 3 ·N −1 ·m −1 ), showing an order-of-magnitude improvement over the P0 and CrC10 coatings. The P0 and CrC10 coatings predominantly exhibited abrasive wear modes. Surprisingly, the worn surface of the BC10 coating was very slight without detectable scratches or delamination, which was dominated by oxidative wear.
作者机构：
[Li, Lixiong; Zeng, Guanghao] Hunan City Univ, Coll Mech & Elect Engn, Yiyang 413000, Peoples R China.;[Wen, Bing] Hunan City Univ, Coll Informat & Elect Engn, Yiyang 413000, Peoples R China.
通讯机构：
[Li, LX ] H;Hunan City Univ, Coll Mech & Elect Engn, Yiyang 413000, Peoples R China.
关键词：
Index Terms-Photovoltaic;maximum power point tracking;newton interpolation calculation;bacterial foraging optimization;partial shading conditions
摘要：
solar power generating system's I-V curve exhibits nonlinear properties. Under the condition environmental change, the P-V characteristic curve of the photovoltaic array has multiple power peaks, which increases the complexity of power tracking. To address the challenge power point tracking under sudden environmental changes, this paper introduces an enhanced maximum power point tracking strategy utilizing an improved bacterial foraging optimization algorithm. The Newton interpolation method is used to initialize the bacterial position near the global maximum power point, and the bacterial foraging algorithm has the advantage random direction selection. When solving the optimization problem, the proposed algorithm can greatly reduce the number of iterations and improve the solution accuracy. This paper introduces a new representation approach for initialized bacterial position. The area near the maximal power point identified using the Newton interpolation approach. The proposed method is verified through computer simulation.
摘要：
Fatigue failure of joints is a critical factor affecting structural safety design. This study investigates the failure mechanism of aluminum (Al)-steel tubular joints fabricated via magnetic pulse crimping (MPC) using multiscale characterization techniques. Shear effects caused the thinning of the Al tube, which induced the formation of a notch on the inner surface. The mechanical interlocking of the material and the notch effect led to stress concentration, thereby promoting fatigue crack initiation (FCI) at the notch. Fracture morphology indicated that FCI was a mixture of intergranular and transgranular fracture. Interestingly, under higher stress conditions (58.5 MPa), the fatigue crack propagation (FCP) rate was extremely fast. The crack propagation process lacked a steady-state stage, with no distinct fatigue striations forming before fracture occurred. The features of the dimples were the main characteristic of final fracture (FF). Electron backscattered diffraction (EBSD) results showed that the differences in plastic deformation degree, dislocation density, and grain Schmid factor (SF) value were the main causes of intergranular and transgranular fracture in FCI.
Fatigue failure of joints is a critical factor affecting structural safety design. This study investigates the failure mechanism of aluminum (Al)-steel tubular joints fabricated via magnetic pulse crimping (MPC) using multiscale characterization techniques. Shear effects caused the thinning of the Al tube, which induced the formation of a notch on the inner surface. The mechanical interlocking of the material and the notch effect led to stress concentration, thereby promoting fatigue crack initiation (FCI) at the notch. Fracture morphology indicated that FCI was a mixture of intergranular and transgranular fracture. Interestingly, under higher stress conditions (58.5 MPa), the fatigue crack propagation (FCP) rate was extremely fast. The crack propagation process lacked a steady-state stage, with no distinct fatigue striations forming before fracture occurred. The features of the dimples were the main characteristic of final fracture (FF). Electron backscattered diffraction (EBSD) results showed that the differences in plastic deformation degree, dislocation density, and grain Schmid factor (SF) value were the main causes of intergranular and transgranular fracture in FCI.
期刊：
Journal of Materials Research and Technology,2025年38:490-496 ISSN：2238-7854
通讯作者：
Xu, J;Jiang, B;Wang, QH
作者机构：
[Zhao, Jun; Yuan, Yueyang; Liu, Jinkang] Hunan City Univ, Sch Mech & Elect Engn, Yiyang 413002, Peoples R China.;[Xu, Jun] Guangdong Acad Sci, Inst New Mat, Guangdong Prov Key Lab Met Toughening & Applicat, Guangzhou 510650, Peoples R China.;[Jiang, Bin] Chongqing Univ, Coll Mat Sci & Engn, Natl Engn Res Ctr Magnesium Alloys, Chongqing 400044, Peoples R China.;[Lei, Bin] Guangxi Univ, Sch Resources Environm & Mat, Nanning 530004, Peoples R China.;[Shi, Xuejiao] Zhongchuang Haitong Intelligent Technol Co Ltd, Changsha 410021, Peoples R China.
通讯机构：
[Wang, QH ] Y;[Xu, J ] G;[Jiang, B ] C;Guangdong Acad Sci, Inst New Mat, Guangdong Prov Key Lab Met Toughening & Applicat, Guangzhou 510650, Peoples R China.;Chongqing Univ, Coll Mat Sci & Engn, Natl Engn Res Ctr Magnesium Alloys, Chongqing 400044, Peoples R China.
关键词：
Mg-Gd alloy;Zn and Li alloying;Microstructure evolution;Mechanical property
摘要：
Effects of Zn and Li alloying on microstructural evolution and mechanical properties of extruded Mg-1Gd alloys were investigated. The addition of single Zn leaded to significant grain refinement in Mg-1Gd alloy, whereas Li alloying induced remarkable grain coarsening. The average grain sizes of the extruded Mg-1Gd, Mg-1Gd-1.5Zn, Mg-1Gd-1.5Li and Mg-1Gd-1.5Zn-1.5Li alloys were ∼21.9, ∼15.5, ∼35.8 and ∼31.2 μm, respectively. Single Zn alloying significantly improved the yield strength and ductility of the extruded Mg-1Gd alloy. The improvement of yield strength in the extruded Mg-1Gd-1.5Zn alloy were mainly associated with the fine grain size, dispersed fine Mg 3 Zn 3 Gd 2 particles and Zn solute atoms. In addition, the ductility enhancement with single Zn addition was mainly linked to grain refining. However, single Zn alloying resulted in a slightly increase of the yield strength, which was associated with the competitive interplay of texture strengthening and grain coarsening. Further, a striking yield strength enhancement was observed with the synergistic addition of Zn and Li, which was primarily benefited from a strong basal texture, despite grain coarsening. In addition, the reduced ductility of the extruded Mg-1Gd-1.5Li and Mg-1Gd-1.5Zn-1.5Li alloys was ascribed to a combined effect of the enhanced basal texture development and grain coarsening.
Effects of Zn and Li alloying on microstructural evolution and mechanical properties of extruded Mg-1Gd alloys were investigated. The addition of single Zn leaded to significant grain refinement in Mg-1Gd alloy, whereas Li alloying induced remarkable grain coarsening. The average grain sizes of the extruded Mg-1Gd, Mg-1Gd-1.5Zn, Mg-1Gd-1.5Li and Mg-1Gd-1.5Zn-1.5Li alloys were ∼21.9, ∼15.5, ∼35.8 and ∼31.2 μm, respectively. Single Zn alloying significantly improved the yield strength and ductility of the extruded Mg-1Gd alloy. The improvement of yield strength in the extruded Mg-1Gd-1.5Zn alloy were mainly associated with the fine grain size, dispersed fine Mg 3 Zn 3 Gd 2 particles and Zn solute atoms. In addition, the ductility enhancement with single Zn addition was mainly linked to grain refining. However, single Zn alloying resulted in a slightly increase of the yield strength, which was associated with the competitive interplay of texture strengthening and grain coarsening. Further, a striking yield strength enhancement was observed with the synergistic addition of Zn and Li, which was primarily benefited from a strong basal texture, despite grain coarsening. In addition, the reduced ductility of the extruded Mg-1Gd-1.5Li and Mg-1Gd-1.5Zn-1.5Li alloys was ascribed to a combined effect of the enhanced basal texture development and grain coarsening.
摘要：
In this study, an ideal inorganic phosphate (IP) matrix composite coating was successfully designed by component optimization strategy. The tribological behavior and wear mechanism of the coating were investigated from 100 to 500 degrees C. Proper amounts of solid lubricants greatly enhanced the hardness, adhesion, wear resistance, and roughness. Mullite fibers (MFs) increased the toughness and load-carrying capacity, which effectively stabilized the wear process. IP270MF is the optimal coating and has excellent friction-reduction properties. The friction coefficient of the coating was 0.20, which was 56.5% lower than that of the substrate. The formation of phosphate macromolecular film improved the lubrication performance and reduced the curing temperature, preventing foil damage. Nevertheless, considerable water loss at high temperatures resulted in the binder becoming embrittled, which reduced adhesion. The range of the average friction coefficient was 0.31 to 0.48 between 100 and 500 degrees C. The IP270MF coating had the maximum wear resistance (1.6 x 10-5mm3 N-1 m-1) and hardness (151 HV) at 200 degrees C. The wear mechanism was dominated by adhesive wear at low temperatures and fatigue wear at temperatures of 300 degrees C or higher. The soft IP270MF coating is expected to provide effective lubrication in foil bearing applications.
关键词：
Mg-Sn-Zn alloy;Ce and Gd addition;Strength-ductility synergy;VPSC simulation;Deformation mechanisms
摘要：
The effects of incorporating dilute Gd and Ce on the microstructure and mechanical properties of Mg-0.5Sn-0.3Zn (TZ00, wt%) alloys are systematically revealed. The results indicate that the co-addition of 0.3 wt% Gd and 0.3 wt% Ce can significantly reduce the grain size from 40.8 μm to 12.0 μm, enhance dynamic recrystallization, and attenuate the intensity of basal texture. Furthermore, plenty of micron- and nano-scale (Gd, Ce)MgSn phases are precipitated. In comparison with the TZ00 alloy, the Mg-0.5Sn-0.3Zn-0.3Gd-0.3Ce alloy (TZGE0000, wt%) displays synergistic improvements in strength and ductility. The corresponding tensile yield strength (TYS), ultimate tensile strength (UTS), and elongation (EL) are 214.1 MPa, 297.4 MPa, and 23.5 %, respectively. The primary reason for this strength improvement is the combined effects of grain refinement and (Gd, Ce)MgSn nano-phase strengthening, while the ductility enhancement is mainly due to the refined grain size, weakened basal texture, increased activation of prismatic slip and {10−12} tensile twinning. Additionally, relative Visco-Plastic Self-Consistent (VPSC) simulations confirm that the combined addition of Gd and Ce can promote the activation of non-basal slip and {10−12} tensile twinning during the deformation process. In more detail, basal and prismatic slips are the primary deformation mechanisms during tensile loading, together with a minor occurrence of {10−12} tensile twinning and pyramidal slip coordination deformations. Conversely, {10−12} tensile twinning predominates during the compression deformation.
The effects of incorporating dilute Gd and Ce on the microstructure and mechanical properties of Mg-0.5Sn-0.3Zn (TZ00, wt%) alloys are systematically revealed. The results indicate that the co-addition of 0.3 wt% Gd and 0.3 wt% Ce can significantly reduce the grain size from 40.8 μm to 12.0 μm, enhance dynamic recrystallization, and attenuate the intensity of basal texture. Furthermore, plenty of micron- and nano-scale (Gd, Ce)MgSn phases are precipitated. In comparison with the TZ00 alloy, the Mg-0.5Sn-0.3Zn-0.3Gd-0.3Ce alloy (TZGE0000, wt%) displays synergistic improvements in strength and ductility. The corresponding tensile yield strength (TYS), ultimate tensile strength (UTS), and elongation (EL) are 214.1 MPa, 297.4 MPa, and 23.5 %, respectively. The primary reason for this strength improvement is the combined effects of grain refinement and (Gd, Ce)MgSn nano-phase strengthening, while the ductility enhancement is mainly due to the refined grain size, weakened basal texture, increased activation of prismatic slip and {10−12} tensile twinning. Additionally, relative Visco-Plastic Self-Consistent (VPSC) simulations confirm that the combined addition of Gd and Ce can promote the activation of non-basal slip and {10−12} tensile twinning during the deformation process. In more detail, basal and prismatic slips are the primary deformation mechanisms during tensile loading, together with a minor occurrence of {10−12} tensile twinning and pyramidal slip coordination deformations. Conversely, {10−12} tensile twinning predominates during the compression deformation.
摘要：
Purpose: To assess the accuracies of airway resistance (R-aw) and compliance (C-rs) calculations using the expiratory time constant (RCexp) method as well as the accuracy of P-mus estimation in obstructive lung models. Methods: A Respironics V60 ventilator was connected to an active lung simulator. The driving pressure was maintained at 5-10 cmH(2)O and positive end-expiration pressure (PEEP) was 5 cmH(2)O. Maximal P-mus, estimated based on equations of motion and respiratory mechanical properties, was calculated by the RCexp method to derive respiratory system compliance (C-rs) and inspiratory (R-insp) and expiratory (R-exp) resistance. Results: During PAV, the assist proportion was adjusted to 55% and 40% with P-mus of 5 and 10 cmH(2)O, respectively. P-mus measurement errors were <20% of the preset values in most lung conditions. In the active lung model with PAV, an overestimation of Raw was found in the normal resistance condition, and R-insp was underestimated in the severe obstructive model (P < 0.01). Crs was overestimated significantly except in the severe obstructive model at a P-mus of 10 cmH(2)O (all P < 0.01). Using the RCexp method, the target of <= 20% between the calculated and preset values in airway resistance was achieved in most obstructive models at a P-mus of 5 cmH(2)O. Conclusions: The RCexp method might provide real-time assessments of respiratory mechanics (elastance and resistance) in the PAV mode. With low inspiratory effort, the estimation error was acceptable (<20%) in most obstructive lung models.
摘要：
Previous studies have indicated an association between neutrophil extracellular traps (NETs) and acute respiratory distress syndrome (ARDS). This study aimed to investigate the potential causal effects of NETs and NETs-related biomarkers on ARDS or vice-versa. A two-sample Mendelian randomization (MR) utilizing genome-wide association studies (GWAS) data was employed to analyze the causality. The primary analysis was conducted using inverse-variance weighted (IVW) methods; weighted median, MR-Egger, and weighted model methods were used to validate the results. Horizontal pleiotropy and outlier detection were assessed via MR-Egger and MR pleiotropy residual sum and outlier (MR-PRESSO), respectively; Cochran's Q test evaluated heterogeneity, while Leave-one-out analyses were used to evaluate the presence of predominant instrumental variables (IVs). IVW method suggested causal associations between genetically predicted IL-13 and a higher risk of ARDS [OR (95%CI) = 1.52 (1.03-2.23), P = 0.047], while there was no causal effect of other factors on ARDS (all P > 0.05). Also, ARDS had no effect on NETs and NETs-related biomarkers (all P > 0.05). Cochran's Q confirmed no significant heterogeneity. MR-Egger regression ruled out horizontal pleiotropy's influence, and MR-PRESSO analysis identified no outliers, reinforcing the study's findings. This MR study established a causal relationship between IL-13 and ARDS, suggesting its potential role as a therapeutic target and biomarker of ARDS. Future work should delve into the underlying mechanisms and clinical applications.
期刊：
International Communications in Heat and Mass Transfer,2025年164:108861 ISSN：0735-1933
通讯作者：
Xiong, ZH
作者机构：
[Xiong, Zhihong] Hunan City Univ, Sch Mech & Elect Engn, Yiyang 413000, Hunan, Peoples R China.;[Chen, Nanzhong; Xiong, Zhihong] Cent South Univ, Coll Mech & Elect Engn, Changsha 410083, Hunan, Peoples R China.
通讯机构：
[Xiong, ZH ] H;Hunan City Univ, Sch Mech & Elect Engn, Yiyang 413000, Hunan, Peoples R China.
关键词：
The main bearing of TBM;CFD simulation;Oil-air two-phase flow;Slewing bearing lubrication test bench
摘要：
The main bearing of a TBM is a large-scale, low-speed, heavy-load slewing bearing, which is crucial for effective lubrication and heat dissipation. In this paper, CFD simulations were conducted to analyze the oil-air two-phase flow under different oil supply rates, inner ring speeds, and oil immersion heights. The simulations were validated with a slewing bearing lubrication test bench. The results demonstrate that the main bearing exhibits a layered oil-air two-phase flow. When the oil supply rate is increased, the oil volume fraction in the main air phase rises, and the auxiliary thrust roller chamber is more significantly affected. Moreover, increasing the rotation speed and immersion height leads to an increase in the interface height and an expansion of the main oil phase region, while having a negligible impact on the oil volume fraction of the main air phase.
The main bearing of a TBM is a large-scale, low-speed, heavy-load slewing bearing, which is crucial for effective lubrication and heat dissipation. In this paper, CFD simulations were conducted to analyze the oil-air two-phase flow under different oil supply rates, inner ring speeds, and oil immersion heights. The simulations were validated with a slewing bearing lubrication test bench. The results demonstrate that the main bearing exhibits a layered oil-air two-phase flow. When the oil supply rate is increased, the oil volume fraction in the main air phase rises, and the auxiliary thrust roller chamber is more significantly affected. Moreover, increasing the rotation speed and immersion height leads to an increase in the interface height and an expansion of the main oil phase region, while having a negligible impact on the oil volume fraction of the main air phase.
摘要：
Laser-based glass frit bonding presents considerable advantages, including fast bonding speed and minimal thermal impact, showing significant application prospects in the packaging of temperature-sensitive optoelectronic devices. In this study, the individual effects of critical process parameters on bonding performance have been investigated through single-factor experiments. Response surface methodology is employed to design experiments systematically for the laser-based glass frit bonding process, focusing on exploring the interactive effects among these process parameters. The Box-Behnken design method is implemented for experimental setup, and a regression model has been developed to analyze the resulting data. Analysis of variance, 3D response surface plots, and contour plots are conducted to comprehensively evaluate the interaction effects of parameters on the bonding seam width and strength. The mathematical model is validated and an optimal combination of process parameters is identified, which significantly enhances the bonding quality. The optimized process parameters are also applied for the laser bonding of square-shaped seam to validate the feasibility of the optimized results and to promote the engineering application of glass laser-based glass frit bonding technology in microelectronic component packaging. Inspection of the bonded specimens shows excellent formation quality of the square-shaped bonding seams, confirming the methodology’s effectiveness in advancing optoelectronic packaging technology.
Laser-based glass frit bonding presents considerable advantages, including fast bonding speed and minimal thermal impact, showing significant application prospects in the packaging of temperature-sensitive optoelectronic devices. In this study, the individual effects of critical process parameters on bonding performance have been investigated through single-factor experiments. Response surface methodology is employed to design experiments systematically for the laser-based glass frit bonding process, focusing on exploring the interactive effects among these process parameters. The Box-Behnken design method is implemented for experimental setup, and a regression model has been developed to analyze the resulting data. Analysis of variance, 3D response surface plots, and contour plots are conducted to comprehensively evaluate the interaction effects of parameters on the bonding seam width and strength. The mathematical model is validated and an optimal combination of process parameters is identified, which significantly enhances the bonding quality. The optimized process parameters are also applied for the laser bonding of square-shaped seam to validate the feasibility of the optimized results and to promote the engineering application of glass laser-based glass frit bonding technology in microelectronic component packaging. Inspection of the bonded specimens shows excellent formation quality of the square-shaped bonding seams, confirming the methodology’s effectiveness in advancing optoelectronic packaging technology.
作者机构：
[Zhou, Li; Zhou, L] Hunan City Univ, Sch Mech & Elect Engn, Yiyang 413001, Peoples R China.;[Liu, Yan] Hunan City Univ, Coll Informat & Elect Engn, Yiyang 413001, Peoples R China.
通讯机构：
[Zhou, L ] H;Hunan City Univ, Sch Mech & Elect Engn, Yiyang 413001, Peoples R China.
关键词：
Object detection;generic object tracking using regression networks;tracking learning detection;intelligent robots;Laplace probability density
摘要：
The development of intelligent robot has always been an important research direction in the field of artificial intelligence, and the object detection of robot is the basis of intelligent perception and autonomous action. This study proposes an improved object detection algorithm which integrates two kinds of intelligent robot object detection techniques. In this process, the relationship between the center position of the target in the frame used for object detection and tracking is analyzed. It uses Laplace probability density as the parameter to calculate the center position relationship, and joins the correction network to correct the feature point positioning. The object re-capture function is added to solve the problem of object loss in the long-term object detection task, and the classifier is used to realize the object recognition. The results show that when the number of targets in the image reaches 20, the capture accuracy of the two data sets remains above 98.7%. In the intersection to union ratio test, when the real rectangular box contained 2M pixels, the intersection to union ratio of the method proposed in this study remains at or above 0.989. When conducting actual application memory usage tests, the proposed method maintains a memory usage of less than 2000Mb at runtime. It is shown that this method has better target detection efficiency and quality, and the requirement of hardware is lower.
摘要：
Depletion of fossil fuel resources at a high speed and increasing demand for energy supply for various purposes in today's life integrated with industry has led to collective contemplation for the optimal and maximum utilization of fossil fuels through the implementation of multigeneration systems. In the presented study, a multigeneration system for cooling, power, freshwater, and Hydrogen production is proposed and investigated from exergy, energy, and economic viewpoints through a specific scenario. A case study is performed, revealing that the system can deliver a net output power of 16,251.8 kW, a cooling load of 15,905.0 kW, produce freshwater at a rate of 3.891 kg/s, and generate hydrogen at 0.284 kg/h. The energy and exergy efficiencies of the system are 60.48 % and 32.55 %, respectively. An economic analysis shows a payback period of 0.474 years. A parametric evaluation is performed to perceive the system operation in various conditions. Subsequently, a multi-objective optimization using the MOPSO-LINMAP method is conducted to identify the optimal operating conditions for the system. The optimization results are compared with the case study findings, demonstrating further improvements in performance metrics. The optimized system achieves a slightly higher energy efficiency of 61.62 % and a lower payback period of 0.40 years, underscoring the benefits of the optimization process. This study highlights the potential of the proposed system to efficiently and economically meet the demands for power, hydrogen, cooling, and freshwater in various applications.
摘要：
Effects of Sn, Mn, and their combined additions on microstructural characteristic and tensile properties of extruded Mg-1Gd (G1) alloy are explored. Compared to the sole Sn or Mn addition, an excellent grain refining is happened with the Sn and Mn combined addition. The average grain size of G1, Mg-1Gd-0.8Sn (GS10), Mg-1Gd0.7Mn (GM10) and Mg-1Gd-0.8Sn-0.7Mn (GSM100) alloys is 21.3, 10.1, 12.8 and 6.8 mu m, respectively. The sole Mn addition enhances the strength and ductility of G1 alloy. The forming the fine alpha-Mn particles and grain refining are attributed to the improved properties of GM10 alloy. The sole Sn addition increases the yield strength of G1 alloy along extrusion direction (ED), but it decreases along transverse direction (TD), The inhomogeneous distribution of coarse GdMgSn particles and formation of TD-split texture should play an important role. The combined effects of Sn and Mn additions guarantee high strength-ductility synergy of GSM100 alloy. The GSM100 alloy exhibits the ultimate strength, yield strength and ductility of 276, 158 MPa and 24.7 % along ED, and 253, 157 MPa and 17.5 % along TD, respectively. The jointly effect of the fine grains, a lot of fine GdMgSn and alpha-Mn particles, the texture weakening and Sn solute atom contributes to the enhancement of properties of GSM100 alloy.
作者机构：
[Chen, Changqing; Chen, Chang] Hunan City Univ, Sch Mech & Elect Engn, Yiyang 413000, Peoples R China.;[Xia, Yunqing; Chen, Changqing; Chen, Chang] Xiangtan Motor Co Ltd, Xiangtan 411201, Peoples R China.;[Tang, Weihua] Hunan Elect Power Design Inst Co LTD, China Energy Engn Grp, Changsha 410007, Peoples R China.
通讯机构：
[Chen, CQ ] H;Hunan City Univ, Sch Mech & Elect Engn, Yiyang 413000, Peoples R China.;Xiangtan Motor Co Ltd, Xiangtan 411201, Peoples R China.
摘要：
In order to solve the problem of frequency modulation power deviation caused by the randomness and fluctuation of wind power outputs, a method of auxiliary wind power frequency modulation capacity allocation based on the data decomposition of a "flywheel + lithium battery" hybrid-energy storage system was proposed. Firstly, the frequency modulation power deviation caused by the uncertainty of wind power is decomposed by the successive variational mode decomposition (SVMD) method, and the mode function is segmented and reconstructed by high and low frequencies. Secondly, a mathematical model is established to maximize the economic benefit of energy storage considering the frequency modulation mileage, and quantum particle swarm optimization is used to solve the target model considering the charging and discharging power of energy storage and the charging state constraints to obtain the optimal hybrid-energy storage configuration. Finally, the simulation results show that, in the step disturbance, the Delta fmax of the hybrid-energy storage mode is reduced by 37.9% and 15.3%, respectively, compared with single-energy storage. Under continuous disturbance conditions, compared with the single-energy storage mode, the Delta fp_v is reduced by 52.73%, 43.72%, 60.71%, and 47.62%, respectively. The frequency fluctuation range is obviously reduced, and the frequency stability is greatly improved.
摘要：
The role of a shock generator in the fuel distribution of a scramjet engine is highly significant. In this article, the usage of the erected 3-lobe nozzle in the existence of a shock generator for fuel injection inside a supersonic combustion chamber is fully studied. A three-dimensional model of the extruded 3-lobe nozzle with two altitudes of 4 mm and 2 mm is produced to disclose the importance of the produced vortex upstream/downstream by the usage of the extruded injector. Comprehensive computational analysis is done to investigate the mixing efficiency and fuel diffusion of the proposed jet configuration. Impacts of the coaxial inward air jet on the hydrogen dispersion of the annual extruded 3-lobe injector are also revealed in the present research. The results of the flow structure indicate that the produced vortex upstream of the erected nozzle improves the fuel dispersion behind the hydrogen jet. Our findings show that the effects of injector height are more considerable than the use of an inner air jet for advance of the fuel mixing within the combustor of a scramjet engine.
摘要：
Our aim with this paper is to model and investigate the vibration and damping of a new hybrid composite shell. The considered composite cylindrical shell includes an FGM anisogrid lattice shell perfectly filled with viscoelastic foams. The modeling of the lattice part composed of spiral and hoop ribs is accomplished according to a global continuous standard based on orthotropic deep shells. The distribution pattern of the metal and ceramic constituents along the lattice ribs is specified by a power law. The homogenizations between ceramic and metal phases within the ribs, as well as between the FGM lattice structure and foam, are governed by the rule of mixtures. Based on the transferred Kelvin–Voigt viscoelastic scheme, the dynamic moduli of the foam portion are acquired. Because viscoelastic foam is a soft material, the higher-order shear deformation shell theory is used to estimate the system's displacement components. After emanating the dynamic equations by Hamilton's principle, the Chebyshev collocation-based semi-numerical method is implemented to detect the system's frequencies and loss factors. The comprehensive results show the role of each composite characteristic in the vibration and damping behavior of the defined structure.
Our aim with this paper is to model and investigate the vibration and damping of a new hybrid composite shell. The considered composite cylindrical shell includes an FGM anisogrid lattice shell perfectly filled with viscoelastic foams. The modeling of the lattice part composed of spiral and hoop ribs is accomplished according to a global continuous standard based on orthotropic deep shells. The distribution pattern of the metal and ceramic constituents along the lattice ribs is specified by a power law. The homogenizations between ceramic and metal phases within the ribs, as well as between the FGM lattice structure and foam, are governed by the rule of mixtures. Based on the transferred Kelvin–Voigt viscoelastic scheme, the dynamic moduli of the foam portion are acquired. Because viscoelastic foam is a soft material, the higher-order shear deformation shell theory is used to estimate the system's displacement components. After emanating the dynamic equations by Hamilton's principle, the Chebyshev collocation-based semi-numerical method is implemented to detect the system's frequencies and loss factors. The comprehensive results show the role of each composite characteristic in the vibration and damping behavior of the defined structure.
