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In this study, the dynamical stability of spinning axially graded micro and nanotubes transporting fluid rested on the Kerr foundation is analyzed. A detailed parametric study is performed to clari...

In view of the problems of large overshoot and large oscillation frequency in cur?rent furnace temperature control, based on the development of intelligent control theory, expert control, fuzzy control, and neural network control in intelligent control theory are combined with proportional integral derivative (PID) control. The intelligent PID control algorithm is used to carry out numerical simulation and experimental research on these several control algorithms. The results show that the adjustment effect of the intelligent PID control algorithm is significantly better than the traditional PID control algorithm. Among them, the fuzzy self-tuning PID control algorithm and the fuzzy immune PID control algorithm are feasible in the application of furnace temperature control. The neural network PID control algorithm It also has good development and application potential.

For the ring surface of a hydraulic cylinder, grid and striped textures have been demonstrated in many previous works to easily provide a conductive oil path, which increases the difficulty of generating converging wedges and are harmful to the formation of dynamic pressure lubrication, especially for full lubrication. Moreover, these studies used an orthogonal design method to study the hydrodynamic lubrication effect and friction performance of the surface without considering the comprehensive effect of multiple parameters with simultaneous changes, which may introduce errors into the simulation analysis. In this work, a diamond-like, non-conductive texture, which mimics shark skin, is developed and optimised to determine the optimal texture morphology while simultaneously considering the influence of multiple parameters, including the diamond angle, axial length ratio, and area occupancy, to optimise the surface of the friction pair. The results show that under the same working conditions, the lift of the diamond texture is nine times greater than that of the striped texture, while its friction coefficient is only one-quarter of that of the striped texture, which will greatly improve the friction and responsiveness of the hydraulic cylinder.

Screw press is a kind of dehydration machines of simple structure, low cost and reliable operation and is widely used in the food processing industry. Screw assembly is the core component of screw press, the force applies on its blade is very complex and prone to failure. This study analyzed the working principle of a type continuous screw press and established mathematical model of its screw mechanism. With the help of large-scale finite element software Patran/Nastran, the screw was analyzed and stress and deformation contour were obtained. It's found that the largest stress appears on the blade root near the discharging end. This study can provides a certain theoretical basis and basic methods to design the more stable screw press.

Automatic filling system is the main equipment in the food machinery industry. With the development of beverage industry and increasing demand of the filling system. The relay control method in traditional Filling machine has low automation and integration level and cannot satisfy the rapid development of automatic production. PLC control method has advantages of simple programming, strong anti-interference and high working reliability, has gradually replace the relay control method. In this study, hardware and software for the automatic filling system based on PLC control is designed, especially the injection section servo control system which adopts the servo motor driver metering pump is carefully analyzed and the filling precision is highly improved.

The Auto Anti-Deviation Drilling System (AADDS) is a high-performance, highly automated vertical drilling hydraulic guide control system. This article takes its power extraction device - driving bearing for the study object, analyzed the single-plunger pump's principle, established the mathematical model of hydraulic guide system, applied Matlab/Simulink to simulate the pump outlet flow under different contour curve of the driving bearing. The results show the oval-shaped bearing is of high efficiency under lower drilling speed, and its performance is better than that of original eccentric-shaped and clover-shaped.

Nowadays, the electro-hydraulic valves are widely used in industrial manufacture for their low-cost and accuracy. Aiming at electro-hydraulic proportional position system, a model of the system is established in Simulink. The system is simulated respectively as the situation of without PID controller, with the PID controller turned by critical ratio method and SRO optimize module. The results show that: the position control system with electro-hydraulic proportional valve is of good static and dynamic characteristics, and meets the requirements of industrial production fairly, and it also indicates the usage of computer automation optimization technology can design the control system with good performance in a short time and can improve the design efficiency.

Appreciable friction and serious wear are common challenges in the operation of advanced manufacturing equipment, and friction pairs may be susceptible to damage even with oil lubrication when point contact exists. In this study, a type of particle-reinforced composite material is introduced for one of the components of a heavy-load contact pair, and the performance improvement of elastohydrodynamic lubrication (EHL) is analyzed considering the rheological properties of non-Newtonian fluids. The Ree–Eyring EHL model is used considering the surface of the particle-reinforced composite, in which the film thickness includes the particle-induced elastic deformation. The problem of inclusions with different eigenstrains is solved by using Galerkin vectors. The influences of particle properties, size, burial depth, and interparticle distance on point-contact EHL are investigated. Furthermore, using several cases, the structural parameters of the particles in the composites are optimized, and an appropriate parameter range is obtained with the goal of reducing friction. Finally, the results for the EHL traction coefficient demonstrate that appropriate particle properties, size, burial depth, and interparticle distance can effectively reduce the traction coefficient in heavy-load contact.

Hydraulic servo cylinder is an important component of the hydraulic system. It directly affects the static and dynamic characteristics of the hydraulic system. The first generation of hydraulic cylinder with rubber seals has poor dynamic performance. It is not adapted to the hydraulic system with high frequency. This restricts the development of hydraulic cylinder. So a kind of hydraulic cylinder with variable clearance is proposed on the basis of the research about the second generation of hydraulic cylinder with constant clearance seal. The sealing of this hydraulic cylinder is realized by variable clearance. Theoretical analysis, mathematical modeling, simulation research, experimental verification and applications proved that the third generation of hydraulic cylinders has perfect static and dynamic performance and longer working life. It can be applied to the hydraulic transmission and hydraulic servo system with high frequency response and high-speed. The proposed technology can be extended to hydraulic components with small deformation requirements, and promote the innovation of hydraulic technology.

The dynamic response test to the subgrade plays a very important role in railway construction and a new in-situ test system is proposed. This paper presents the application of non-dominated sorting genetic algorithm-II (NSGA-II) to analyze the stability of the supporting equipment for track subgrade dynamic response in-situ test device. Its stability is related with the extension length of the hydraulic cylinders and the backward condition of the supporting equipment - the hydraulic excavator. The problem is formulated as a multi-objective optimization problem with the objective of maximizing the supporting force for the test device. An 85 tons excavator is picked as the case to study. The first optimal results show the excavator may not support the test system successfully. After redesigning the boom and adding its weight and length as new parameters, the second optimize results indicate the test device can work normally. DOI: http://dx.doi.org/10.11591/telkomnika.v11i12.3986 Full Text: PDF

In this paper, we take the railway subgrade dynamic response test system as the study object, the laboratory test reaction frameâ??s model factors were analyzed through the finite element analysis software MSC.Patran/Nastran. The former six-order original frequencies and vibration modes of the frame were caculated and evaluated in detail. Then we studied its transient response under two working conditions: when itâ??s fully loaded and suddenly unloaded, and the deformation displacement curves of the key points of the frame were obtained. These results provide a basis for the detailed study to the mechanical behavior of the frame and setting the proper working frequencies of the hydraulic servo excitation cylinder to avoid the resonance.

Subgrade bears both the weight of superstructures and the impacts of running trains. Its stability affects the line smoothness directly, but in situ testing method on it is inadequate. This paper presents a railway roadbed in situ testing device, the key component of which is an excitation hydraulic servo cylinder that can output the static pressure and dynamic pressure simultaneously to simulate the force of the trains to the subgrade. The principle of the excitation system is briefly introduced, and the transfer function of the closed-loop force control system is derived and simulated; that, it shows without control algorithm, the dynamic response is very low and the following performance is quite poor. So, the improvedadaptive model following control (AMFC) algorithm based on direct state method is adopted. Then, control block diagram is built and simulated with the input of different waveforms and frequencies. The simulation results show that the system has been greatly improved; the output waveform can follow the input signal much better except for a little distortion when the signal varies severely. And the following performance becomes even better as the load stiffness increases.