Negative pressure plays a very important role in compact spinning system.To know airflow field and its distribution is helpful to look into the condensing principle of fiber bundle.Therefore,computational fluid dynami...Negative pressure plays a very important role in compact spinning system.To know airflow field and its distribution is helpful to look into the condensing principle of fiber bundle.Therefore,computational fluid dynamics(CFD)software was used to simulate airflow field in this paper.Airflow velocity distributions both in different fiber layers and under different negative pressures were discussed.The results indicate that airflow velocity in upper layer of the fiber bundle is greater than that in lower layer.Airflow velocities in both X and Y axis directions have a positive correlation with negative pressure.It can provide a theoretical base to make high quality compact yarns in productive practice.展开更多
On the basis of analyzing the typical kinds of balloon controllers used now, this article provides a new type one named Fixed Bell Shaped Balloon Controller. Experiments have been made to verify the function of it. Re...On the basis of analyzing the typical kinds of balloon controllers used now, this article provides a new type one named Fixed Bell Shaped Balloon Controller. Experiments have been made to verify the function of it. Results indicated that the facility has quite good effect on the improvement of yarn quality and properties in addition to controlling yarn tension.展开更多
Jute fibre properties,viz. linear density,mechanical properties,and fibre staple length were analyzed in this paper. Morphology,lignin content,and composition analysis for jute fibres were investigated in order to giv...Jute fibre properties,viz. linear density,mechanical properties,and fibre staple length were analyzed in this paper. Morphology,lignin content,and composition analysis for jute fibres were investigated in order to give further understanding of the fibre properties changing during the chemical treatment and yarn producing processes. The results show that jute properties are greatly changed during the processes of chemical treatment,breaking carding,and finisher carding,whereas slight changes can be found in the processes of drawing,roving,and spinning.展开更多
By nature, pineapple fiber (PALF) obtained from pineapple leaf is a smooth, shiny and white natural cellulosic fiber. In current investigation of spinning technique for pineapple leaf fiber based on cotton spinning me...By nature, pineapple fiber (PALF) obtained from pineapple leaf is a smooth, shiny and white natural cellulosic fiber. In current investigation of spinning technique for pineapple leaf fiber based on cotton spinning method comparison of produced yarn properties has been reported. For one of the investigations of this study, the fibers were cut into staple length and various properties of fibers were analyzed. Data and results acquired from this illustrated that there is excellent spinnability on the fiber. Two separate researches were conducted with consideration to produce resultant yarn by spinning of PALF. Yarn derived by solo spinning technique of 100% PALF and PALF blending with polyester and cotton fibers through binary blending technique in equal proportion has been spun, then yarn count, tensile properties, yarn evenness, hairiness have been evaluated and analyzed. The results from numerical simulations analysis indicated that yarn obtained from the Pineapple leaf fiber (PALF) had great potential to be used in apparels.展开更多
Radiative cooling textiles with spectrally selective surfaces offer a promising energy-efficient approach for sub-ambient cooling of outdoor objects and individuals.However,the spectrally selective mid-infrared emissi...Radiative cooling textiles with spectrally selective surfaces offer a promising energy-efficient approach for sub-ambient cooling of outdoor objects and individuals.However,the spectrally selective mid-infrared emission of these textiles significantly hinders their efficient radiative heat exchange with self-heated objects,thereby posing a significant challenge to their versatile cooling applicability.Herein,we present a bicomponent blow spinning strategy for the production of scalable,ultra-flexible,and healable textiles featuring a tailored dual gradient in both chemical composition and fiber diameter.The gradient in the fiber diameter of this textile introduces a hierarchically porous structure across the sunlight incident area,thereby achieving a competitive solar reflectivity of 98.7%on its outer surface.Additionally,the gradient in the chemical composition of this textile contributes to the formation of Janus infrared-absorbing surfaces:The outer surface demonstrates a high mid-infrared emission,whereas the inner surface shows a broad infrared absorptivity,facilitating radiative heat exchange with underlying self-heated objects.Consequently,this textile demonstrates multi-scenario radiative cooling capabilities,enabling versatile outdoor cooling for unheated objects by 7.8℃ and self-heated objects by 13.6℃,compared to commercial sunshade fabrics.展开更多
Based on the flow simulation in the condensing zone of compact spinning with lattice apron and a bead-elastic rod dynamic model of the flexible fiber,trajectories of fibers with different negative pressure are simulat...Based on the flow simulation in the condensing zone of compact spinning with lattice apron and a bead-elastic rod dynamic model of the flexible fiber,trajectories of fibers with different negative pressure are simulated by specially designed Matlab procedure.Then displacement components of fibers at YZ profile under different negative pressure conditions are extracted and compared.The results show that the fibers of different initial positions gradually converge,and are interlaced for position change in yarn cross-section,caused by the airflow in the condensing zone.Finally,compact-spun yarn with different negative pressure and conventional ring spun yarn are produced and their twists are tested.Both the results of simulation and experiments illustrate the existence of additional twists.Also the relationship between additional twists and negative pressure is verified.展开更多
The fundamental process of predictive maintenance is prognostics and health management,and it is the tool resulting in the development of many algorithms to predict the remaining useful life of industrial equipment.A ...The fundamental process of predictive maintenance is prognostics and health management,and it is the tool resulting in the development of many algorithms to predict the remaining useful life of industrial equipment.A new data-driven predictive maintenance and an architectural impulse,based on a regularized deep neural network using predictive analytics,are proposed successfully for ring spinning technology.The paradigm shift in computational infrastructures enormously puts pressure on large-scale linear and non-linear automated assembly systems to eliminate and cut down unscheduled downtime and unexpected stoppages.The sensor network designed for the scheduling process comprises different critical components of the same spinning machine frames containing more than thousands of spindles attached to them.We established a genetic algorithm based on multi-sensor performance assessment and prediction procedure for the spinning system.Results show that it operates with a relatively less amount of training data sets but takes advantage of larger volumes of data.This integrated system aims to prognosticate abnormalities,disturbances,and failures by providing condition-based monitoring for each component,which makes it more accurate to locate the defined component failures in the current spinning spindles by using smart agents during the operations through the neural sensing network.A case study has provided to demonstrate the feasibility of the proposed predictive model for highly dynamic,high-speed textile spinning system through real-time data sensing and signal processing via the industrial Internet of Things.展开更多
In this paper, dynamic economic dispatch model is proposed for power systems with bulk wind power integration. The wind turbine generators are assumed to partially undertake the spinning reserve for the thermal genera...In this paper, dynamic economic dispatch model is proposed for power systems with bulk wind power integration. The wind turbine generators are assumed to partially undertake the spinning reserve for the thermal generator. A double-layer optimization model is proposed. The outer layer use the differential evolution to search for the power output of thermal generators, and the inner layer use the primal-dual interior point method to solve the OPF of the established output state. Finally, the impact of spinning reserve with wind power on power system operating is validated.展开更多
In this paper the formulation of finite element analysis for frame casing problems of theharmonic type is described. Attention is paid to the OE spinning rotor bearing assembly (RBA)’ sdynamic model, whose harmonic p...In this paper the formulation of finite element analysis for frame casing problems of theharmonic type is described. Attention is paid to the OE spinning rotor bearing assembly (RBA)’ sdynamic model, whose harmonic parameters, such as natural frequencies and modal shapes, aresolved by means of structural analysis program using personal computer, i.e. SAP84 software. Ac-cording to orthogonal factorial design table (OFDT), the predominant sensitive influential factors(PSIF) of RBA are determined.展开更多
In this paper, a successfully studied and developed master - slave muld - microcomputers control system based on PC - BUS for hollow spindle fancy yarn spinning machine, mainly Its overall scheme, software and hardwar...In this paper, a successfully studied and developed master - slave muld - microcomputers control system based on PC - BUS for hollow spindle fancy yarn spinning machine, mainly Its overall scheme, software and hardware construction, is introduced. Spinning experiments show that the system achieves satisfactory result. This system can solve the diftkultles of mechatronical fusion between domestic hollow splndk fancy yarn spuming muchine and its microcomputer control technology.展开更多
This paper presents an evolutionary stochastic production simulation to solve the optimal spinning reserve configuration problem in power system with wind integrated. Equivalent load curve is generated with considerin...This paper presents an evolutionary stochastic production simulation to solve the optimal spinning reserve configuration problem in power system with wind integrated. Equivalent load curve is generated with considering the wind power forecasting deviation and generation scheduling of hydropower plant in different water periods. The equivalent load duration curve (ELDC), redrawn from equivalent load curve is the core of stochastic production simulation which focuses on random outage of generator and load fluctuation. The optimal spinning reserve model is established around the reliability index Expected Energy Not Served (ENNS). The optimal scheduling of spinning reserve is reached while the cost of purchasing spinning reserve is equal to the outage loss. At last, results of the optimal spinning reserve model tested in Hainan power grid help reduce the costs of spinning reserve configuration.展开更多
An internal state variable(ISV)model was established according to the experimental results of hot plane strain compression(PSC)to predict the microstructure evolution during hot spinning of ZK61 alloy.The effects of t...An internal state variable(ISV)model was established according to the experimental results of hot plane strain compression(PSC)to predict the microstructure evolution during hot spinning of ZK61 alloy.The effects of the internal variables were considered in this ISV model,and the parameters were optimized by genetic algorithm.After validation,the ISV model was used to simulate the evolution of grain size(GS)and dynamic recrystallization(DRX)fraction during hot spinning via Abaqus and its subroutine Vumat.By comparing the simulated results with the experimental results,the application of the ISV model was proven to be reliable.Meanwhile,the strength of the thin-walled spun ZK61 tube increased from 303 to 334 MPa due to grain refinement by DRX and texture strengthening.Besides,some ultrafine grains(0.5μm)that played an important role in mechanical properties were formed due to the proliferation,movement,and entanglement of dislocations during the spinning process.展开更多
Fiber fabrics have been wildly utilized for solar interracial evaporators to address freshwater scarcity.However,the complex and expensive manufacturing processes remain limited to their scalable development.Herein,a ...Fiber fabrics have been wildly utilized for solar interracial evaporators to address freshwater scarcity.However,the complex and expensive manufacturing processes remain limited to their scalable development.Herein,a fabric-based Janus interracial evaporator is efficiently fabricated on a large scale by integrating an extremely innovative self-designed melt-centrifugal spinning technology with spray coating technology.The prepared fabric-based Janus interfacial evaporator has differential hydrophilicity,uneven surfaces,and channels that allow moisture escape.Benefiting from the excellent photothermai conversion of graphene oxide and the charge transfer actions of titanium dioxide,such a multifunction evaporator can reach a high evaporation rate of 1.72 kg m^(-2)h^(-1)under 1 sun irradiation,a superior antibacterial rate of 99%,excellent photocatalytic degradation,and effective thermoelectric ability simultaneously.Moreover,it also shows fantastic performance in salt resistance,recyclable evaporation,and real desalination,This work demonstrates a high-efficiency,cost-effective,multifunctional,and scalable strategy for high-performance fiber fabrics solar interfacial evaporation.展开更多
The fiber optic sensing technology provides data support in structural health monitoring of the macro facilities,including design,construction,and maintenance of bridges,tunnels,ports and other infrastructures.In this...The fiber optic sensing technology provides data support in structural health monitoring of the macro facilities,including design,construction,and maintenance of bridges,tunnels,ports and other infrastructures.In this paper,a distributed vibration sensing system is proved to be responsive to a single touch over a 1.8-m-long equivalent fiber segment,covering a vibration frequency from 5 Hz to 25 kHz.The sensing fiber was arranged as an S type layout on the bridge to recognize the standing state,windblown disturbance,and walking vibration.Moreover,the knocking and climbing events are recognized fiber laying spinning lines and hanging on the fences,respectively.The demonstration shows an accurate positioning and sensitive vibration monitoring applied on the automated three-dimensional(3D) printed bridge,which is applicable to all kinds of 3D printed facilities as intelligent sensory neuro-networks.展开更多
Mesophase pitch carbon fibers have an ultra-high modulus and thermal conductivity that are unmatched by other carbon fibers,making it irreplaceable in many fields.However,due to the high temperature dependence of the ...Mesophase pitch carbon fibers have an ultra-high modulus and thermal conductivity that are unmatched by other carbon fibers,making it irreplaceable in many fields.However,due to the high temperature dependence of the viscosity of the melted pitch and the poor mechanical properties of pitch fibers,it is difficult to reduce the fiber diameter when using continuous spinning.We used the Mathworks Matlab software to optimize the mesophase pitch melt spinning model and to simulate the effects of spinning temperature,mass flow rate,winder speed,and quenching air temperature near the spinneret on the maximum shear rate during drawing.Simulation results demonstrate that applying gradient cooling to the melt upon exiting the spinneret significantly reduces the maximum shear rate and extends the drawing zone,thereby promoting the spinning stability and helping reduce the fiber diameter.In the experiment,instead of quenching in air,we applied gradient cooling to the melt,whose temperature decreased according to the equation Ta=298+278exp(−11.4z),where Ta is the final air temperature in Kelvin,and z is the distance from the spinneret in meters.It was found the gradient cooling greatly improved the draw-down ratio,reducing the average diameter of the pitch fibers from 20.8 to 13.1μm,along with improved process stability.The experimental results are in excellent agreement with the predictions.At the same time,the tensile strength of the 1150℃ carbonized fibers increased from 0.6 to 1.1 GPa.Although the degree of orientation of the fibers decreased slightly,the tight bonding between microcrystals,the suppression of splitting,and the smaller diameter improved the mechanical properties of carbon fibers.This study provides an effective method for reducing the fiber diameter while improving continuity.展开更多
Precision,speed and cost efficiency are all indispensable,especially in challenging times.Rieter has put together a powerful portfolio for ITMA ASIA+CITME 2025 that gives spinning mills the chance to actively shape th...Precision,speed and cost efficiency are all indispensable,especially in challenging times.Rieter has put together a powerful portfolio for ITMA ASIA+CITME 2025 that gives spinning mills the chance to actively shape the future through intelligent automation.This is a key milestone on the way to achieving Rieter’s vision 2027-the fully automated spinning mill.展开更多
Sheet metal spinning is an incremental forming process for producing axisymmetric thinwalled parts through continuous local deformation under the action of rollers.While studying the spinning process by finite element...Sheet metal spinning is an incremental forming process for producing axisymmetric thinwalled parts through continuous local deformation under the action of rollers.While studying the spinning process by finite element(FE)method,a critical bottleneck is the enormous simulation time.For beating off this challenge,a novel multi-mesh method is developed.The method can dynamically track the movement of rollers and adaptively refine the mesh.Thus,a locally refined quadrilateral computation mesh can be generated in the locally-deforming zone and reduce the unnecessary fine elements outside the locally-deforming zone.In the multi-mesh system,the fine elements and coarse elements are extracted from a storage mesh and a background mesh,respectively.Meanwhile,the hanging nodes in the locally refined mesh are removed by designing 4-refinement templates.Between computation mesh and storage mesh,a bi-cubic parametric surface fitting algorithm and accurate remapping methods are conducted to transmit geometric information and physical fields.The proposed method has been verified by two spinning processes.The results suggest that the method can save time by up to about 67%with satisfactory accuracy,especially for distributions of thickness and strain compared with the fully refined mesh.展开更多
Based on the Timoshenko beam theory,this paper proposes a nonlocal bi-gyroscopic model for spinning functionally graded(FG)nanotubes conveying fluid,and the thermal–mechanical vibration and stability of such composit...Based on the Timoshenko beam theory,this paper proposes a nonlocal bi-gyroscopic model for spinning functionally graded(FG)nanotubes conveying fluid,and the thermal–mechanical vibration and stability of such composite nanostructures under small scale,rotor,and temperature coupling effects are investigated.The nanotube is composed of functionally graded materials(FGMs),and different volume fraction functions are utilized to control the distribution of material properties.Eringen’s nonlocal elasticity theory and Hamilton’s principle are applied for dynamical modeling,and the forward and backward precession frequencies as well as 3D mode configurations of the nanotube are obtained.By conducting dimensionless analysis,it is found that compared to the Timoshenko nano-beam model,the conventional Euler–Bernoulli(E-B)model holds the same flutter frequency in the supercritical region,while it usually overestimates the higher-order precession frequencies.The nonlocal,thermal,and flowing effects all can lead to buckling or different kinds of coupled flutter in the system.The material distribution of the P-type FGM nanotube can also induce coupled flutter,while that of the S-type FGM nanotube has no impact on the stability of the system.This paper is expected to provide a theoretical foundation for the design of motional composite nanodevices.展开更多
The dynamic recrystallization(DRX)behavior and texture formation mechanism in an AZ31 magnesium alloy wheel hub during the spinning process were investigated.Analysis using optical microscopy,electron backscatter diff...The dynamic recrystallization(DRX)behavior and texture formation mechanism in an AZ31 magnesium alloy wheel hub during the spinning process were investigated.Analysis using optical microscopy,electron backscatter diffraction,transmission electron microscopy,and finite element simulation revealed that continuous dynamic recrystallization(CDRX)and grain boundary bulging occurred simultaneously throughout the spinning process,leading to an increased proportion of DRXed grain areas.The newly formed DRXed grains largely retained the orientations of their deformed parent grains.The spinning process had two stages:initially,deformation was driven by basalslip as the roller contacted the alloy and descended to its lowest point.In the later stage,pyramidal<c+a>slips became predominant as additional force was applied along the spinning direction(SD),forming a final texture with the c-axis tilting±15°towards the SD.This texture development led to discernible anisotropy in tensile properties along the SD and the tangential direction(TD).展开更多
Fiber quality measurement in spinning preparation is crucial for optimizing waste and meeting yarn quality specifications.The brand-new Uster AFIS 6–the next-generation laboratory instrument from Uster Technologies–...Fiber quality measurement in spinning preparation is crucial for optimizing waste and meeting yarn quality specifications.The brand-new Uster AFIS 6–the next-generation laboratory instrument from Uster Technologies–uniquely tests man-made fiber properties in addition to cotton.It provides critical data to optimize fiber process control for cotton,man-made fibers,and blended yarns.展开更多
基金Key Project in National Science & Technology Pillar Program,China(No.2007BAE41B04)
文摘Negative pressure plays a very important role in compact spinning system.To know airflow field and its distribution is helpful to look into the condensing principle of fiber bundle.Therefore,computational fluid dynamics(CFD)software was used to simulate airflow field in this paper.Airflow velocity distributions both in different fiber layers and under different negative pressures were discussed.The results indicate that airflow velocity in upper layer of the fiber bundle is greater than that in lower layer.Airflow velocities in both X and Y axis directions have a positive correlation with negative pressure.It can provide a theoretical base to make high quality compact yarns in productive practice.
文摘On the basis of analyzing the typical kinds of balloon controllers used now, this article provides a new type one named Fixed Bell Shaped Balloon Controller. Experiments have been made to verify the function of it. Results indicated that the facility has quite good effect on the improvement of yarn quality and properties in addition to controlling yarn tension.
基金National Key Technologies R&D Program of China (No.2007BAE41B01)
文摘Jute fibre properties,viz. linear density,mechanical properties,and fibre staple length were analyzed in this paper. Morphology,lignin content,and composition analysis for jute fibres were investigated in order to give further understanding of the fibre properties changing during the chemical treatment and yarn producing processes. The results show that jute properties are greatly changed during the processes of chemical treatment,breaking carding,and finisher carding,whereas slight changes can be found in the processes of drawing,roving,and spinning.
文摘By nature, pineapple fiber (PALF) obtained from pineapple leaf is a smooth, shiny and white natural cellulosic fiber. In current investigation of spinning technique for pineapple leaf fiber based on cotton spinning method comparison of produced yarn properties has been reported. For one of the investigations of this study, the fibers were cut into staple length and various properties of fibers were analyzed. Data and results acquired from this illustrated that there is excellent spinnability on the fiber. Two separate researches were conducted with consideration to produce resultant yarn by spinning of PALF. Yarn derived by solo spinning technique of 100% PALF and PALF blending with polyester and cotton fibers through binary blending technique in equal proportion has been spun, then yarn count, tensile properties, yarn evenness, hairiness have been evaluated and analyzed. The results from numerical simulations analysis indicated that yarn obtained from the Pineapple leaf fiber (PALF) had great potential to be used in apparels.
基金financial support from the National Natural Science Foundation of China(Grant No.52273067,52233006)the Fundamental Research Funds for the Central Universities(Grant No.2232023A-03)+3 种基金the Shuguang Program of Shanghai Education Development Foundation and Shanghai Municipal Education Commission(Grant No.23SG29)the Natural Science Foundation of Shanghai(Grant No.24ZR1402400)the Shanghai Scientific and Technological Innovation Project(Grant No.24520713000)Innovation Program of Shanghai Municipal Education Commission(Grant No.2021-01-07-00-03-E00108).
文摘Radiative cooling textiles with spectrally selective surfaces offer a promising energy-efficient approach for sub-ambient cooling of outdoor objects and individuals.However,the spectrally selective mid-infrared emission of these textiles significantly hinders their efficient radiative heat exchange with self-heated objects,thereby posing a significant challenge to their versatile cooling applicability.Herein,we present a bicomponent blow spinning strategy for the production of scalable,ultra-flexible,and healable textiles featuring a tailored dual gradient in both chemical composition and fiber diameter.The gradient in the fiber diameter of this textile introduces a hierarchically porous structure across the sunlight incident area,thereby achieving a competitive solar reflectivity of 98.7%on its outer surface.Additionally,the gradient in the chemical composition of this textile contributes to the formation of Janus infrared-absorbing surfaces:The outer surface demonstrates a high mid-infrared emission,whereas the inner surface shows a broad infrared absorptivity,facilitating radiative heat exchange with underlying self-heated objects.Consequently,this textile demonstrates multi-scenario radiative cooling capabilities,enabling versatile outdoor cooling for unheated objects by 7.8℃ and self-heated objects by 13.6℃,compared to commercial sunshade fabrics.
文摘Based on the flow simulation in the condensing zone of compact spinning with lattice apron and a bead-elastic rod dynamic model of the flexible fiber,trajectories of fibers with different negative pressure are simulated by specially designed Matlab procedure.Then displacement components of fibers at YZ profile under different negative pressure conditions are extracted and compared.The results show that the fibers of different initial positions gradually converge,and are interlaced for position change in yarn cross-section,caused by the airflow in the condensing zone.Finally,compact-spun yarn with different negative pressure and conventional ring spun yarn are produced and their twists are tested.Both the results of simulation and experiments illustrate the existence of additional twists.Also the relationship between additional twists and negative pressure is verified.
基金the National Natural Science Founda-tion of China(No.51475301)the Fundamental Hesearch Funds for the Central Universities of China(No.2232017A-03)。
文摘The fundamental process of predictive maintenance is prognostics and health management,and it is the tool resulting in the development of many algorithms to predict the remaining useful life of industrial equipment.A new data-driven predictive maintenance and an architectural impulse,based on a regularized deep neural network using predictive analytics,are proposed successfully for ring spinning technology.The paradigm shift in computational infrastructures enormously puts pressure on large-scale linear and non-linear automated assembly systems to eliminate and cut down unscheduled downtime and unexpected stoppages.The sensor network designed for the scheduling process comprises different critical components of the same spinning machine frames containing more than thousands of spindles attached to them.We established a genetic algorithm based on multi-sensor performance assessment and prediction procedure for the spinning system.Results show that it operates with a relatively less amount of training data sets but takes advantage of larger volumes of data.This integrated system aims to prognosticate abnormalities,disturbances,and failures by providing condition-based monitoring for each component,which makes it more accurate to locate the defined component failures in the current spinning spindles by using smart agents during the operations through the neural sensing network.A case study has provided to demonstrate the feasibility of the proposed predictive model for highly dynamic,high-speed textile spinning system through real-time data sensing and signal processing via the industrial Internet of Things.
文摘In this paper, dynamic economic dispatch model is proposed for power systems with bulk wind power integration. The wind turbine generators are assumed to partially undertake the spinning reserve for the thermal generator. A double-layer optimization model is proposed. The outer layer use the differential evolution to search for the power output of thermal generators, and the inner layer use the primal-dual interior point method to solve the OPF of the established output state. Finally, the impact of spinning reserve with wind power on power system operating is validated.
文摘In this paper the formulation of finite element analysis for frame casing problems of theharmonic type is described. Attention is paid to the OE spinning rotor bearing assembly (RBA)’ sdynamic model, whose harmonic parameters, such as natural frequencies and modal shapes, aresolved by means of structural analysis program using personal computer, i.e. SAP84 software. Ac-cording to orthogonal factorial design table (OFDT), the predominant sensitive influential factors(PSIF) of RBA are determined.
文摘In this paper, a successfully studied and developed master - slave muld - microcomputers control system based on PC - BUS for hollow spindle fancy yarn spinning machine, mainly Its overall scheme, software and hardware construction, is introduced. Spinning experiments show that the system achieves satisfactory result. This system can solve the diftkultles of mechatronical fusion between domestic hollow splndk fancy yarn spuming muchine and its microcomputer control technology.
文摘This paper presents an evolutionary stochastic production simulation to solve the optimal spinning reserve configuration problem in power system with wind integrated. Equivalent load curve is generated with considering the wind power forecasting deviation and generation scheduling of hydropower plant in different water periods. The equivalent load duration curve (ELDC), redrawn from equivalent load curve is the core of stochastic production simulation which focuses on random outage of generator and load fluctuation. The optimal spinning reserve model is established around the reliability index Expected Energy Not Served (ENNS). The optimal scheduling of spinning reserve is reached while the cost of purchasing spinning reserve is equal to the outage loss. At last, results of the optimal spinning reserve model tested in Hainan power grid help reduce the costs of spinning reserve configuration.
基金supported by the National Natural Science Foundation of China(No.51905123)Major Scientific and Technological Innovation Program of Shandong Province,China(Nos.2020CXGC010303,2022ZLGX04)Key R&D Programme of Shandong Province,China(No.2022JMRH0308).
文摘An internal state variable(ISV)model was established according to the experimental results of hot plane strain compression(PSC)to predict the microstructure evolution during hot spinning of ZK61 alloy.The effects of the internal variables were considered in this ISV model,and the parameters were optimized by genetic algorithm.After validation,the ISV model was used to simulate the evolution of grain size(GS)and dynamic recrystallization(DRX)fraction during hot spinning via Abaqus and its subroutine Vumat.By comparing the simulated results with the experimental results,the application of the ISV model was proven to be reliable.Meanwhile,the strength of the thin-walled spun ZK61 tube increased from 303 to 334 MPa due to grain refinement by DRX and texture strengthening.Besides,some ultrafine grains(0.5μm)that played an important role in mechanical properties were formed due to the proliferation,movement,and entanglement of dislocations during the spinning process.
基金the National Key Research and Development Program of China(Grant No.2022YFC3901902)the National Natural Science Foundation of China(Grant Nos.52203037,52103031,and 52073107)。
文摘Fiber fabrics have been wildly utilized for solar interracial evaporators to address freshwater scarcity.However,the complex and expensive manufacturing processes remain limited to their scalable development.Herein,a fabric-based Janus interracial evaporator is efficiently fabricated on a large scale by integrating an extremely innovative self-designed melt-centrifugal spinning technology with spray coating technology.The prepared fabric-based Janus interfacial evaporator has differential hydrophilicity,uneven surfaces,and channels that allow moisture escape.Benefiting from the excellent photothermai conversion of graphene oxide and the charge transfer actions of titanium dioxide,such a multifunction evaporator can reach a high evaporation rate of 1.72 kg m^(-2)h^(-1)under 1 sun irradiation,a superior antibacterial rate of 99%,excellent photocatalytic degradation,and effective thermoelectric ability simultaneously.Moreover,it also shows fantastic performance in salt resistance,recyclable evaporation,and real desalination,This work demonstrates a high-efficiency,cost-effective,multifunctional,and scalable strategy for high-performance fiber fabrics solar interfacial evaporation.
基金supported by the National Natural Science Foundation of China (No.6210031560)the Natural Science Foundation of Hebei Province (No.A2020202013)the Natural Science Foundation of Tianjin City (No.21JCQNJC00780)。
文摘The fiber optic sensing technology provides data support in structural health monitoring of the macro facilities,including design,construction,and maintenance of bridges,tunnels,ports and other infrastructures.In this paper,a distributed vibration sensing system is proved to be responsive to a single touch over a 1.8-m-long equivalent fiber segment,covering a vibration frequency from 5 Hz to 25 kHz.The sensing fiber was arranged as an S type layout on the bridge to recognize the standing state,windblown disturbance,and walking vibration.Moreover,the knocking and climbing events are recognized fiber laying spinning lines and hanging on the fences,respectively.The demonstration shows an accurate positioning and sensitive vibration monitoring applied on the automated three-dimensional(3D) printed bridge,which is applicable to all kinds of 3D printed facilities as intelligent sensory neuro-networks.
文摘Mesophase pitch carbon fibers have an ultra-high modulus and thermal conductivity that are unmatched by other carbon fibers,making it irreplaceable in many fields.However,due to the high temperature dependence of the viscosity of the melted pitch and the poor mechanical properties of pitch fibers,it is difficult to reduce the fiber diameter when using continuous spinning.We used the Mathworks Matlab software to optimize the mesophase pitch melt spinning model and to simulate the effects of spinning temperature,mass flow rate,winder speed,and quenching air temperature near the spinneret on the maximum shear rate during drawing.Simulation results demonstrate that applying gradient cooling to the melt upon exiting the spinneret significantly reduces the maximum shear rate and extends the drawing zone,thereby promoting the spinning stability and helping reduce the fiber diameter.In the experiment,instead of quenching in air,we applied gradient cooling to the melt,whose temperature decreased according to the equation Ta=298+278exp(−11.4z),where Ta is the final air temperature in Kelvin,and z is the distance from the spinneret in meters.It was found the gradient cooling greatly improved the draw-down ratio,reducing the average diameter of the pitch fibers from 20.8 to 13.1μm,along with improved process stability.The experimental results are in excellent agreement with the predictions.At the same time,the tensile strength of the 1150℃ carbonized fibers increased from 0.6 to 1.1 GPa.Although the degree of orientation of the fibers decreased slightly,the tight bonding between microcrystals,the suppression of splitting,and the smaller diameter improved the mechanical properties of carbon fibers.This study provides an effective method for reducing the fiber diameter while improving continuity.
文摘Precision,speed and cost efficiency are all indispensable,especially in challenging times.Rieter has put together a powerful portfolio for ITMA ASIA+CITME 2025 that gives spinning mills the chance to actively shape the future through intelligent automation.This is a key milestone on the way to achieving Rieter’s vision 2027-the fully automated spinning mill.
基金co-supported by the supports of Guangdong Basic and Applied Basic Research Foundation(No.2019B1515120047)the National Natural Science Foundation of China(No.52130507)。
文摘Sheet metal spinning is an incremental forming process for producing axisymmetric thinwalled parts through continuous local deformation under the action of rollers.While studying the spinning process by finite element(FE)method,a critical bottleneck is the enormous simulation time.For beating off this challenge,a novel multi-mesh method is developed.The method can dynamically track the movement of rollers and adaptively refine the mesh.Thus,a locally refined quadrilateral computation mesh can be generated in the locally-deforming zone and reduce the unnecessary fine elements outside the locally-deforming zone.In the multi-mesh system,the fine elements and coarse elements are extracted from a storage mesh and a background mesh,respectively.Meanwhile,the hanging nodes in the locally refined mesh are removed by designing 4-refinement templates.Between computation mesh and storage mesh,a bi-cubic parametric surface fitting algorithm and accurate remapping methods are conducted to transmit geometric information and physical fields.The proposed method has been verified by two spinning processes.The results suggest that the method can save time by up to about 67%with satisfactory accuracy,especially for distributions of thickness and strain compared with the fully refined mesh.
基金National Natural Science Foundation of China,12372025,Feng Liang,12072311,Feng Liang.
文摘Based on the Timoshenko beam theory,this paper proposes a nonlocal bi-gyroscopic model for spinning functionally graded(FG)nanotubes conveying fluid,and the thermal–mechanical vibration and stability of such composite nanostructures under small scale,rotor,and temperature coupling effects are investigated.The nanotube is composed of functionally graded materials(FGMs),and different volume fraction functions are utilized to control the distribution of material properties.Eringen’s nonlocal elasticity theory and Hamilton’s principle are applied for dynamical modeling,and the forward and backward precession frequencies as well as 3D mode configurations of the nanotube are obtained.By conducting dimensionless analysis,it is found that compared to the Timoshenko nano-beam model,the conventional Euler–Bernoulli(E-B)model holds the same flutter frequency in the supercritical region,while it usually overestimates the higher-order precession frequencies.The nonlocal,thermal,and flowing effects all can lead to buckling or different kinds of coupled flutter in the system.The material distribution of the P-type FGM nanotube can also induce coupled flutter,while that of the S-type FGM nanotube has no impact on the stability of the system.This paper is expected to provide a theoretical foundation for the design of motional composite nanodevices.
基金funded by the National Natural Science Foundation of China(No.52204407)the Natural Science Foundation of Jiangsu Province,China(No.BK20220595)the China Postdoctoral Science Foundation(No.2022M723689)。
文摘The dynamic recrystallization(DRX)behavior and texture formation mechanism in an AZ31 magnesium alloy wheel hub during the spinning process were investigated.Analysis using optical microscopy,electron backscatter diffraction,transmission electron microscopy,and finite element simulation revealed that continuous dynamic recrystallization(CDRX)and grain boundary bulging occurred simultaneously throughout the spinning process,leading to an increased proportion of DRXed grain areas.The newly formed DRXed grains largely retained the orientations of their deformed parent grains.The spinning process had two stages:initially,deformation was driven by basalslip as the roller contacted the alloy and descended to its lowest point.In the later stage,pyramidal<c+a>slips became predominant as additional force was applied along the spinning direction(SD),forming a final texture with the c-axis tilting±15°towards the SD.This texture development led to discernible anisotropy in tensile properties along the SD and the tangential direction(TD).
文摘Fiber quality measurement in spinning preparation is crucial for optimizing waste and meeting yarn quality specifications.The brand-new Uster AFIS 6–the next-generation laboratory instrument from Uster Technologies–uniquely tests man-made fiber properties in addition to cotton.It provides critical data to optimize fiber process control for cotton,man-made fibers,and blended yarns.
