A numerical method to predict the bursting strength of filament wound composite rocket motor case is proposed here.This method can evaluate the longitudinal stress evolution of each composite layer as impregnated fila...A numerical method to predict the bursting strength of filament wound composite rocket motor case is proposed here.This method can evaluate the longitudinal stress evolution of each composite layer as impregnated filaments with fiber tension are wound layer by layer,and consider the effects of accumulated stress and deformation during filament winding on the bursting strength of composite case.Taking∅520 mm composite cases as a case study,the filament-winding-process-induced stress and deformation as well as progressive damage behavior are numerically predicted,followed by a comparison with experimental results.The numerical results show that the predicted bursting pressures for composite cases manufactured on the mandrels with and without a flexible component are 14.20 MPa and 21.40 MPa,respectively.These values exhibit slight deviation from the measured pressures of 13.50 MPa and 21.57 MPa.Moreover,the predicted damage locations,situated respectively in the dome and cylinder,agree well with the experimental observation.These observations indicate that use of flexible component reduces the load-bearing capacity of the domes.Furthermore,it validates the reliability and accuracy of the proposed numerical method in predicting the bursting strength of composite cases.展开更多
The constant winding tension can make the filament arranged in order. The stress distribution between the filament balance fully gives play to the enhancement of filament, and increases the intensive workload of the c...The constant winding tension can make the filament arranged in order. The stress distribution between the filament balance fully gives play to the enhancement of filament, and increases the intensive workload of the composite winding material. This paper conducts the mechanical analysis for the unwinding roller and tension measuring roller of the cylindrical winding machine so that gets the mechanical model, gives error compensation formula caused by the radius change of the yarn group in the unwinding side, designs the closed-loop control system and utilizes the dynamical- integral PID control strategy to achieve the tension control during the process of the cylindrical winding.展开更多
Unmanned combat aerial vehicles require lightweight,stealth-capable exhaust systems.However,traditional metallic nozzles increase radar detectability and reduce range,while advanced composites offer high performance b...Unmanned combat aerial vehicles require lightweight,stealth-capable exhaust systems.However,traditional metallic nozzles increase radar detectability and reduce range,while advanced composites offer high performance but are expensive.Therefore,to improve the operational range and survivability of unmanned combat aerial vehicles,a lightweight,high-temperature-resistant,oxidation-resistant,and low-observable composite exhaust nozzle is developed to replace conventional metallic straight-type nozzles.The nozzle features a double serpentine shape to reduce radar and infrared signatures and is manufactured as a monolithic structure using the filament winding process,accommodating the complex geometry and large size(length:1.8 m,width:0.8 m).The exhaust nozzle consists of a ceramic matrix composite made of silicon carbide fibers and a silicon oxycarbide matrix,which absorbs and scatters radio frequency signals while withstanding prolonged exposure to high-temperature(700℃)oxidizing environments typical of engine exhaust gases.The polysiloxane resin used to produce the silicon oxycarbide matrix poses significant challenges owing to its low tackiness and high viscosity variations depending on the presence of nanoparticles,making filament winding difficult.These challenges are addressed by optimizing resin viscosity and winding pattern design.As a result,the tensile strength of the composite specimens fabricated with the optimized viscosity increases by 228.03% before pyrolysis and 97.68%after pyrolysis,compared with that of the non-optimized specimens.In addition,the density and tensile strength of the composite processed via three cycles of polymer infiltration and pyrolysis increased by 13.08% and 80.37%,respectively,compared to those of the non-densified composite.High-temperature oxidation and flame tests demonstrate exceptional thermal and oxidative stability.Furthermore,when compared with carbon fiber-reinforced ceramic matrix composites,the developed composite exhibits a permittivity at least two levels lower and a reflection loss below7 dB within the frequency range of 9.3-10.9 GHz,underscoring its superior electromagnetic stealth performance.展开更多
Filament winding has emerged as the main process for carbon fiber reinforced plastic(CFRP) fabrication, and tension control plays a key role in enhancing the quality of the winding products. With the continuous improv...Filament winding has emerged as the main process for carbon fiber reinforced plastic(CFRP) fabrication, and tension control plays a key role in enhancing the quality of the winding products. With the continuous improvement of prod?uct quality and e ciency, the precision of the tension control system is constantly improving. In this paper, a novel tension control method is proposed, which can regulate the fiber tension and transport speed of the winding process by governing the outputs of three di erent driven rollers(the torque of the unwind roll, the torque of the magnetic powder brake roller, and the speed of the master speed roller) in three levels. The mechanical structures and dynamic models of the driven rollers and idle rollers are established by considering the time?varying features of the roller radius and inertia. Moreover, the influence of parameters and speed variation on fiber tension is investigated using the increment model. Subsequently, the control method is proposed by applying fiber tension in three levels accord?ing to the features of the three driven rollers. An adaptive fuzzy controller is designed for tuning the PID parameters online to control the speed of the master speed roller. Simulation is conducted for verifying the performance and sta?bility of the proposed tension control method by comparing with those of the conventional PID control method. The result reveals that the proposed method outperforms the conventional method. Finally, an experimental platform is constructed, and the proposed system is applied to a winding machine. The performance and stability of the tension control system are demonstrated via a series of experiments using carbon fiber under di erent reference speeds and tensions. This paper proposes a novel tension control method to regulate the fiber tension and transport speed.展开更多
A theory of composite material patch winding is proposed to determine the winding trajectory with a meshed data model. Two different conditions are considered in this study. One is Bridge condition on the concave surf...A theory of composite material patch winding is proposed to determine the winding trajectory with a meshed data model. Two different conditions are considered in this study. One is Bridge condition on the concave surface and the other is Slip line condition in the process of patch winding. This paper presents the judgment principles and corresponding solutions by applying differential geometry theory and space geometry theory. To verify the feasibility of the patch winding method, the winding control code is programmed. Furthermore, the winding experiments on an airplane inlet and a vane are performed. From the experiments, it shows that the patch winding theory has the advantages of flexibility, easy design and application.展开更多
Based on the elastic theory of cylindrical shells and the theory of composite laminates,a prediction model for the residual prestress of the simplified round composite barrel for railgun is established.Only the fibre ...Based on the elastic theory of cylindrical shells and the theory of composite laminates,a prediction model for the residual prestress of the simplified round composite barrel for railgun is established.Only the fibre pretension is considered in this model.A three dimensional numerical simulation for the residual prestress in the railgun barrel is carried out,by combining the temperature differential method with the element birth and death technology.The results obtained by the two methods are compared.It reveals that the distribution trends of residual prestress are consistent.And the difference for residual prestress in the filament wound composite housing of barrel is relatively small.The same finite element method is used to analysis the residual prestress in the non-simplified composite barrels for railgun,which are under different control modes of winding tension.The results mean that the residual prestress in barrel will increase while the taper coefficient for winding is decreasing.Therefore,the sealing performance in bore is improved,but the strength of the filament wound composite housing drops.In addition,the axial and circumferential residual prestress in the filament wound composite housing with constant torque winding are close to the ones in iso-stress design for barrel.展开更多
The FW process is a prefect method of manufacturing FRP composite air vessel resisting high pressure and aerial press vessel.In this paper FW pattern of FRP composite air vessel resisting high pressure was analyzed in...The FW process is a prefect method of manufacturing FRP composite air vessel resisting high pressure and aerial press vessel.In this paper FW pattern of FRP composite air vessel resisting high pressure was analyzed in a nutshell.The stability of FW patterns on end head is very sensitive to changing of pattern parameter.Consequently,its FW pattern was based on geodesic track.The FW angles and on equators depend on the dimension of end part and the condition of geodesic FW.Generally speaking,the polar holes of rocket engine shell are disproportional.Therefore,the FW angles of the shell column are changeable.The feasi-bility of nongeodesic FW of the shell column was discussed in this paper.Furthermore,it expounded the indispensable condition be-tween the length of shell column and the FW friction coefficient.At the same time,the general mathematic models of the movement control of nongeodesic FW were deduced.展开更多
This article presents the results of experimental studies concerning the dynamic deformation and failure of a unidirectional carbon fiber reinforced plastic(T700/LY113)under compression.The test samples were manufactu...This article presents the results of experimental studies concerning the dynamic deformation and failure of a unidirectional carbon fiber reinforced plastic(T700/LY113)under compression.The test samples were manufactured through the filament winding of flat plates.To establish the strain rate dependencies of the strength and elastic modulus of the material,dynamic tests were carried out using a drop tower,the Split Hopkinson Pressure Bar method,and standard static tests.The samples were loaded both along and perpendicular to the direction of the reinforcing fiber.The applicability of the obtained samples for static and dynamic tests was confirmed through finite elementmodeling and the high-speed imaging of the deformation and failure of samples during testing.As a result of the conducted experimental studies,static and dynamic stress-strain curves,time dependencies of deformation and the stress and strain rates of the samples during compression were obtained.Based on these results,the strain rate dependencies of the strength and elasticity modulus in the strain rate range of 0.001-6001/s are constructed.It is shown that the strain rate significantly affects the strength and deformation characteristics of the unidirectional carbon fiber composites under compression.An increase in the strain rate by 5 orders of magnitude increased the strength and elastic modulus along the fiber direction by 42%and 50%,respectively.Perpendicular loading resulted in a strength and elastic modulus increase by 58%and 50%,respectively.The average strength along the fibers at the largest studied strain rate was about 1000MPa.The obtained results can be used to design structural elements made of polymer composite materials operating under dynamic shock loads,as well as to build models of mechanical behavior and failure criteria of such materials,taking into account the strain rate effects.展开更多
The pattern for filament wound toroidal vessels derived from differential geometry is presented. The pattern design and optimization procedure was put forward according to imposed design requirements. The mathematical...The pattern for filament wound toroidal vessels derived from differential geometry is presented. The pattern design and optimization procedure was put forward according to imposed design requirements. The mathematical model and movement equations of winding torns are obtained by analytic geometry. A computer simulation system of filament winding process based on optimal pattern design was developed to verify the correctness and practicability of the winding pattern. The optimum pattern and winding simulation were performed by this system. The simulation results show that the pattern satisfies both winding principles and structural optimization. The recommended design-oriented method can be applied to the preliminary design of filament wound toroidal vessels.展开更多
A multi-objective optimization method was proposed for different dome reinforcement methods of a filament-wound solid rocket motor composite case based on a Radial Basis Function(RBF)model.Progressive damage of the co...A multi-objective optimization method was proposed for different dome reinforcement methods of a filament-wound solid rocket motor composite case based on a Radial Basis Function(RBF)model.Progressive damage of the composite case was considered in a simulation based on Hashin failure criteria,and simulation results were validated by hydraulic burst tests to precisely predict the failure mode,failure position,and burst pressure.An RBF surrogate model was estab-lished and evaluated by Relative Average Absolute Error(RAAE),Relative Maximum Absolute Error(RMAE),Root Mean Squared Error(RMSE),and R^(2)methods to improve the optimization efficient of dome reinforcement.In addition,the Non-dominated Sorting Genetic Algorithm(NSGA-II)was employed to establish multi-objective optimization models of variable-angle and variable-polar-radius dome reinforcements to investigate the coupling effect of the reinforcement angle,reinforcement layers,and reinforcement range on the case performance.Optimal reinforce-ment parameters were obtained and used to establish a progressive damage model of the composite case with dome reinforcement.In accordance with progressive damage analysis,the burst pressure and performance factor were obtained.Results illustrated that variable-angle dome reinforcement was the optimal reinforcement method compared with variable-polar-radius dome reinforcement as it could not only ensure the reinforcement angle’s continuous changing but also decrease the mass of composite materials.Compared with the unreinforced case,the reinforced case exhibited an increase in the burst pressure and performance factor of 36.1%and 23.5%,respectively.展开更多
The control of the stability of the filament tension is one of the crucial techniques ensuring the component quality of the composite materials. The open-loop tension control system, with industrial control computer a...The control of the stability of the filament tension is one of the crucial techniques ensuring the component quality of the composite materials. The open-loop tension control system, with industrial control computer as the core, magnetic particle clutch as the actuator, equipped with compensation technique is researched and manufactured. It can assure the tension control stability of the yarn in filament winding process and increase the control precision of the whole system.展开更多
A new filament winding method developed in this study named MFW （multiple-supply FW） method. It performed a high productivity. In the MFW method, a large number of bobbins are used. Carbon fibers are arranged equian...A new filament winding method developed in this study named MFW （multiple-supply FW） method. It performed a high productivity. In the MFW method, a large number of bobbins are used. Carbon fibers are arranged equiangularly above a mandrel, and they are wound and stacked on the mandrel simultaneously. Furthermore, CFRP pipes with non-crimp structure were made by MFW, and the torsional tests were performed in order to investigate mechanical properties comparing with braided CFRP pipes. These results made clear that the non-crimp structure by MFW was capable to improve torsional properties. The MFW machine produce non-crimp tubular preform with carbon fiber automatically. It is expected to produce non-crimp preforms for automotive parts which required high productivity.展开更多
GFRP poles have been widely used as lighting poles but their use as traffic signs and signal poles is still under development. This paper highlights the literature review and case study of using GFRP poles for traffic...GFRP poles have been widely used as lighting poles but their use as traffic signs and signal poles is still under development. This paper highlights the literature review and case study of using GFRP poles for traffic signs and signal poles in the Eastern Province of Saudi Arabia. The case study details the design of poles, construction, maintenance and their performance. Traffic sign poles were manufactured using filament winding and signal poles using pultrusion process. AASHTO Standard “Specifications for Structural Supports for Highway Signs, Luminaires and Traffic Signals” and ANSI 136.2. were used as materials specification and design for the pole. There is a need to develop dedicated design and construction guidelines to standardize the construction process. Further study about the crash resistance of GFRP poles at different speeds needs to be explored. In addition, the paper presents a high level comparison between the different materials like weight, safety, environmental degradation, strength, service life, durability in an aggressive environment, carbon footprint and economics.展开更多
Toroidal composite vessel winded with fiber is a new kind of structural pressure vessels,which not only has high structure efficiency of compound materials pressure vessel,good security and so on,but also has special ...Toroidal composite vessel winded with fiber is a new kind of structural pressure vessels,which not only has high structure efficiency of compound materials pressure vessel,good security and so on,but also has special shape and the property of u-tilizing toroidal space,and the prospect of the application of toroidal composite vessel winded with fiber is extremely broad.By in-troducing parameters establishment of toroidal vessel and elaborating the principle of filament winding for toroidal vessel,the de-sign model of filament winding machine for toroidal vessel has been introduced,and the design model has been dynamically simu-lated by the software of ADAMS,which will give more referrence for the design of real toroidal vessel twister.展开更多
An optimization procedure is developed for obtaining optimal structural design of filament wound composite pipes with minimum cost utilized in pressurized water and waste-water pipelines.First,the short-term and long-...An optimization procedure is developed for obtaining optimal structural design of filament wound composite pipes with minimum cost utilized in pressurized water and waste-water pipelines.First,the short-term and long-term design constraints dictated by international standards are identified.Then,proper computational tools are developed for predicting the structural properties of the composite pipes based on the design architecture of layers.The developed computational tools are validated by relying on experimental analysis.Then,an integrated design-optimization process is developed to minimize the price as the main objective,taking into account design requirements and manufacturing limitations as the constraints and treating lay-up sequence,fiber volume fraction,winding angle,and the number of total layers as design variables.The developed method is implemented in various case studies,and the results are presented and discussed.展开更多
基金supported by the National Natural Science Foundation of China(No.11902231)the Major Program(JD)of Hubei Province,China(No.2023BAA004).
文摘A numerical method to predict the bursting strength of filament wound composite rocket motor case is proposed here.This method can evaluate the longitudinal stress evolution of each composite layer as impregnated filaments with fiber tension are wound layer by layer,and consider the effects of accumulated stress and deformation during filament winding on the bursting strength of composite case.Taking∅520 mm composite cases as a case study,the filament-winding-process-induced stress and deformation as well as progressive damage behavior are numerically predicted,followed by a comparison with experimental results.The numerical results show that the predicted bursting pressures for composite cases manufactured on the mandrels with and without a flexible component are 14.20 MPa and 21.40 MPa,respectively.These values exhibit slight deviation from the measured pressures of 13.50 MPa and 21.57 MPa.Moreover,the predicted damage locations,situated respectively in the dome and cylinder,agree well with the experimental observation.These observations indicate that use of flexible component reduces the load-bearing capacity of the domes.Furthermore,it validates the reliability and accuracy of the proposed numerical method in predicting the bursting strength of composite cases.
文摘The constant winding tension can make the filament arranged in order. The stress distribution between the filament balance fully gives play to the enhancement of filament, and increases the intensive workload of the composite winding material. This paper conducts the mechanical analysis for the unwinding roller and tension measuring roller of the cylindrical winding machine so that gets the mechanical model, gives error compensation formula caused by the radius change of the yarn group in the unwinding side, designs the closed-loop control system and utilizes the dynamical- integral PID control strategy to achieve the tension control during the process of the cylindrical winding.
基金supported by the Agency for Defense Development Grant Funded by the Korean Government(Grant No.912822501).
文摘Unmanned combat aerial vehicles require lightweight,stealth-capable exhaust systems.However,traditional metallic nozzles increase radar detectability and reduce range,while advanced composites offer high performance but are expensive.Therefore,to improve the operational range and survivability of unmanned combat aerial vehicles,a lightweight,high-temperature-resistant,oxidation-resistant,and low-observable composite exhaust nozzle is developed to replace conventional metallic straight-type nozzles.The nozzle features a double serpentine shape to reduce radar and infrared signatures and is manufactured as a monolithic structure using the filament winding process,accommodating the complex geometry and large size(length:1.8 m,width:0.8 m).The exhaust nozzle consists of a ceramic matrix composite made of silicon carbide fibers and a silicon oxycarbide matrix,which absorbs and scatters radio frequency signals while withstanding prolonged exposure to high-temperature(700℃)oxidizing environments typical of engine exhaust gases.The polysiloxane resin used to produce the silicon oxycarbide matrix poses significant challenges owing to its low tackiness and high viscosity variations depending on the presence of nanoparticles,making filament winding difficult.These challenges are addressed by optimizing resin viscosity and winding pattern design.As a result,the tensile strength of the composite specimens fabricated with the optimized viscosity increases by 228.03% before pyrolysis and 97.68%after pyrolysis,compared with that of the non-optimized specimens.In addition,the density and tensile strength of the composite processed via three cycles of polymer infiltration and pyrolysis increased by 13.08% and 80.37%,respectively,compared to those of the non-densified composite.High-temperature oxidation and flame tests demonstrate exceptional thermal and oxidative stability.Furthermore,when compared with carbon fiber-reinforced ceramic matrix composites,the developed composite exhibits a permittivity at least two levels lower and a reflection loss below7 dB within the frequency range of 9.3-10.9 GHz,underscoring its superior electromagnetic stealth performance.
基金Supported by National Natural Science Foundation of China(Grant No.51575018)
文摘Filament winding has emerged as the main process for carbon fiber reinforced plastic(CFRP) fabrication, and tension control plays a key role in enhancing the quality of the winding products. With the continuous improvement of prod?uct quality and e ciency, the precision of the tension control system is constantly improving. In this paper, a novel tension control method is proposed, which can regulate the fiber tension and transport speed of the winding process by governing the outputs of three di erent driven rollers(the torque of the unwind roll, the torque of the magnetic powder brake roller, and the speed of the master speed roller) in three levels. The mechanical structures and dynamic models of the driven rollers and idle rollers are established by considering the time?varying features of the roller radius and inertia. Moreover, the influence of parameters and speed variation on fiber tension is investigated using the increment model. Subsequently, the control method is proposed by applying fiber tension in three levels accord?ing to the features of the three driven rollers. An adaptive fuzzy controller is designed for tuning the PID parameters online to control the speed of the master speed roller. Simulation is conducted for verifying the performance and sta?bility of the proposed tension control method by comparing with those of the conventional PID control method. The result reveals that the proposed method outperforms the conventional method. Finally, an experimental platform is constructed, and the proposed system is applied to a winding machine. The performance and stability of the tension control system are demonstrated via a series of experiments using carbon fiber under di erent reference speeds and tensions. This paper proposes a novel tension control method to regulate the fiber tension and transport speed.
基金Foundation item： Aeronautical Science Foundation of China （50175020）
文摘A theory of composite material patch winding is proposed to determine the winding trajectory with a meshed data model. Two different conditions are considered in this study. One is Bridge condition on the concave surface and the other is Slip line condition in the process of patch winding. This paper presents the judgment principles and corresponding solutions by applying differential geometry theory and space geometry theory. To verify the feasibility of the patch winding method, the winding control code is programmed. Furthermore, the winding experiments on an airplane inlet and a vane are performed. From the experiments, it shows that the patch winding theory has the advantages of flexibility, easy design and application.
文摘Based on the elastic theory of cylindrical shells and the theory of composite laminates,a prediction model for the residual prestress of the simplified round composite barrel for railgun is established.Only the fibre pretension is considered in this model.A three dimensional numerical simulation for the residual prestress in the railgun barrel is carried out,by combining the temperature differential method with the element birth and death technology.The results obtained by the two methods are compared.It reveals that the distribution trends of residual prestress are consistent.And the difference for residual prestress in the filament wound composite housing of barrel is relatively small.The same finite element method is used to analysis the residual prestress in the non-simplified composite barrels for railgun,which are under different control modes of winding tension.The results mean that the residual prestress in barrel will increase while the taper coefficient for winding is decreasing.Therefore,the sealing performance in bore is improved,but the strength of the filament wound composite housing drops.In addition,the axial and circumferential residual prestress in the filament wound composite housing with constant torque winding are close to the ones in iso-stress design for barrel.
文摘The FW process is a prefect method of manufacturing FRP composite air vessel resisting high pressure and aerial press vessel.In this paper FW pattern of FRP composite air vessel resisting high pressure was analyzed in a nutshell.The stability of FW patterns on end head is very sensitive to changing of pattern parameter.Consequently,its FW pattern was based on geodesic track.The FW angles and on equators depend on the dimension of end part and the condition of geodesic FW.Generally speaking,the polar holes of rocket engine shell are disproportional.Therefore,the FW angles of the shell column are changeable.The feasi-bility of nongeodesic FW of the shell column was discussed in this paper.Furthermore,it expounded the indispensable condition be-tween the length of shell column and the FW friction coefficient.At the same time,the general mathematic models of the movement control of nongeodesic FW were deduced.
基金This research was supported by the Russian Science Foundation(Grant No.21-19-00563,https://rscf.ru/en/project/21-19-00563/)H.M.Sedighi is grateful to the Research Council of Shahid Chamran University of Ahvaz for its financial support(Grant No.SCU.EM1401.98)。
文摘This article presents the results of experimental studies concerning the dynamic deformation and failure of a unidirectional carbon fiber reinforced plastic(T700/LY113)under compression.The test samples were manufactured through the filament winding of flat plates.To establish the strain rate dependencies of the strength and elastic modulus of the material,dynamic tests were carried out using a drop tower,the Split Hopkinson Pressure Bar method,and standard static tests.The samples were loaded both along and perpendicular to the direction of the reinforcing fiber.The applicability of the obtained samples for static and dynamic tests was confirmed through finite elementmodeling and the high-speed imaging of the deformation and failure of samples during testing.As a result of the conducted experimental studies,static and dynamic stress-strain curves,time dependencies of deformation and the stress and strain rates of the samples during compression were obtained.Based on these results,the strain rate dependencies of the strength and elasticity modulus in the strain rate range of 0.001-6001/s are constructed.It is shown that the strain rate significantly affects the strength and deformation characteristics of the unidirectional carbon fiber composites under compression.An increase in the strain rate by 5 orders of magnitude increased the strength and elastic modulus along the fiber direction by 42%and 50%,respectively.Perpendicular loading resulted in a strength and elastic modulus increase by 58%and 50%,respectively.The average strength along the fibers at the largest studied strain rate was about 1000MPa.The obtained results can be used to design structural elements made of polymer composite materials operating under dynamic shock loads,as well as to build models of mechanical behavior and failure criteria of such materials,taking into account the strain rate effects.
文摘The pattern for filament wound toroidal vessels derived from differential geometry is presented. The pattern design and optimization procedure was put forward according to imposed design requirements. The mathematical model and movement equations of winding torns are obtained by analytic geometry. A computer simulation system of filament winding process based on optimal pattern design was developed to verify the correctness and practicability of the winding pattern. The optimum pattern and winding simulation were performed by this system. The simulation results show that the pattern satisfies both winding principles and structural optimization. The recommended design-oriented method can be applied to the preliminary design of filament wound toroidal vessels.
基金co-supported by the National Natural Science Foundation of China(52175311,52175133,12102115,52005446)the Fundamental Research Funds for Central Universities in China(JZ2021HGTA0178,JZ2022HGQA0150).
文摘A multi-objective optimization method was proposed for different dome reinforcement methods of a filament-wound solid rocket motor composite case based on a Radial Basis Function(RBF)model.Progressive damage of the composite case was considered in a simulation based on Hashin failure criteria,and simulation results were validated by hydraulic burst tests to precisely predict the failure mode,failure position,and burst pressure.An RBF surrogate model was estab-lished and evaluated by Relative Average Absolute Error(RAAE),Relative Maximum Absolute Error(RMAE),Root Mean Squared Error(RMSE),and R^(2)methods to improve the optimization efficient of dome reinforcement.In addition,the Non-dominated Sorting Genetic Algorithm(NSGA-II)was employed to establish multi-objective optimization models of variable-angle and variable-polar-radius dome reinforcements to investigate the coupling effect of the reinforcement angle,reinforcement layers,and reinforcement range on the case performance.Optimal reinforce-ment parameters were obtained and used to establish a progressive damage model of the composite case with dome reinforcement.In accordance with progressive damage analysis,the burst pressure and performance factor were obtained.Results illustrated that variable-angle dome reinforcement was the optimal reinforcement method compared with variable-polar-radius dome reinforcement as it could not only ensure the reinforcement angle’s continuous changing but also decrease the mass of composite materials.Compared with the unreinforced case,the reinforced case exhibited an increase in the burst pressure and performance factor of 36.1%and 23.5%,respectively.
文摘The control of the stability of the filament tension is one of the crucial techniques ensuring the component quality of the composite materials. The open-loop tension control system, with industrial control computer as the core, magnetic particle clutch as the actuator, equipped with compensation technique is researched and manufactured. It can assure the tension control stability of the yarn in filament winding process and increase the control precision of the whole system.
文摘A new filament winding method developed in this study named MFW （multiple-supply FW） method. It performed a high productivity. In the MFW method, a large number of bobbins are used. Carbon fibers are arranged equiangularly above a mandrel, and they are wound and stacked on the mandrel simultaneously. Furthermore, CFRP pipes with non-crimp structure were made by MFW, and the torsional tests were performed in order to investigate mechanical properties comparing with braided CFRP pipes. These results made clear that the non-crimp structure by MFW was capable to improve torsional properties. The MFW machine produce non-crimp tubular preform with carbon fiber automatically. It is expected to produce non-crimp preforms for automotive parts which required high productivity.
文摘GFRP poles have been widely used as lighting poles but their use as traffic signs and signal poles is still under development. This paper highlights the literature review and case study of using GFRP poles for traffic signs and signal poles in the Eastern Province of Saudi Arabia. The case study details the design of poles, construction, maintenance and their performance. Traffic sign poles were manufactured using filament winding and signal poles using pultrusion process. AASHTO Standard “Specifications for Structural Supports for Highway Signs, Luminaires and Traffic Signals” and ANSI 136.2. were used as materials specification and design for the pole. There is a need to develop dedicated design and construction guidelines to standardize the construction process. Further study about the crash resistance of GFRP poles at different speeds needs to be explored. In addition, the paper presents a high level comparison between the different materials like weight, safety, environmental degradation, strength, service life, durability in an aggressive environment, carbon footprint and economics.
文摘Toroidal composite vessel winded with fiber is a new kind of structural pressure vessels,which not only has high structure efficiency of compound materials pressure vessel,good security and so on,but also has special shape and the property of u-tilizing toroidal space,and the prospect of the application of toroidal composite vessel winded with fiber is extremely broad.By in-troducing parameters establishment of toroidal vessel and elaborating the principle of filament winding for toroidal vessel,the de-sign model of filament winding machine for toroidal vessel has been introduced,and the design model has been dynamically simu-lated by the software of ADAMS,which will give more referrence for the design of real toroidal vessel twister.
基金The authors acknowledge the financial support provided by the Iranian National Science Foundation(INSF)under contract 4003139.
文摘An optimization procedure is developed for obtaining optimal structural design of filament wound composite pipes with minimum cost utilized in pressurized water and waste-water pipelines.First,the short-term and long-term design constraints dictated by international standards are identified.Then,proper computational tools are developed for predicting the structural properties of the composite pipes based on the design architecture of layers.The developed computational tools are validated by relying on experimental analysis.Then,an integrated design-optimization process is developed to minimize the price as the main objective,taking into account design requirements and manufacturing limitations as the constraints and treating lay-up sequence,fiber volume fraction,winding angle,and the number of total layers as design variables.The developed method is implemented in various case studies,and the results are presented and discussed.
