scholarly journals Modeling, Simulation and Uncertain Optimization of the Gun Engraving System

Mathematics ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 398
Author(s):  
Tong Xin ◽  
Guolai Yang ◽  
Fengjie Xu ◽  
Quanzhao Sun ◽  
Alexandi Minak

The system designed to accomplish the engraving process of a rotating band projectile is called the gun engraving system. To obtain higher performance, the optimal design of the size parameters of the gun engraving system was carried out. First, a fluid–solid coupling computational model of the gun engraving system was built and validated by the gun launch experiment. Subsequently, three mathematic variable values, like performance evaluation indexes, were obtained. Second, a sensitivity analysis was performed, and four high-influence size parameters were selected as design variables. Finally, an optimization model based on the affine arithmetic was set up and solved, and then the optimized intervals of performance evaluation indexes were obtained. After the optimal design, the percent decrease of the maximum engraving resistance force ranged from 6.34% to 18.24%; the percent decrease of the maximum propellant gas temperature ranged from 1.91% to 7.45%; the percent increase of minimum pressure wave of the propellant gas ranged from 0.12% to 0.36%.

2013 ◽  
Vol 785-786 ◽  
pp. 1258-1261
Author(s):  
In Pyo Cha ◽  
Hee Jae Shin ◽  
Neung Gu Lee ◽  
Lee Ku Kwac ◽  
Hong Gun Kim

Topology optimization and shape optimization of structural optimization techniques are applied to transport skate the lightweight. Skate properties by varying the design variables and minimize the maximum stress and strain in the normal operation, while reducing the volume of the objective function of optimal design and Skate the static strength of the constraints that should not degrade compared to the performance of the initial model. The skates were used in this study consists of the main frame, sub frame, roll, pin main frame only structural analysis and optimal design was performed using the finite element method. Simplified initial model set design area and it compared to SM45C, AA7075, CFRP, GFRP was using the topology optimization. Strength does not degrade compared to the initial model, decreased volume while minimizing the stress and strain results, the optimum design was achieved efficient lightweight.


Author(s):  
Kazuhiko Hiramoto ◽  
Taichi Matsuoka ◽  
Akira Fukukita ◽  
Katsuaki Sunakoda

We address a simultaneous optimal design problem of a semi-active control law and design parameters in a vibration control device for civil structures. The Vibration Control Device (VCD) that is being developed by authors is used as the semi-active control device in the present paper. The VCD is composed of a mechanism of a ball screw with a flywheel for the inertial resistance force and an electric motor with an electric circuit for the damping resistance force. A new bang-bang type semi-active control law referred to as Inverse Lyapunov Approach is proposed as the semi-active control law. In the Inverse Lyapunov Approach the Lyapunov function is searched so that performance measures in structural vibration control are optimized in the premise of the bang-bang type semi-active control based on the Lyapunov function. The design parameters to determine the Lyapunov function and the design parameters of the VCD are optimized for the good performance of the semi-active control system. The Genetic Algorithm is employed for the optimal design.


2020 ◽  
Author(s):  
Alamgir Choudhury ◽  
Pavel Ikonomov ◽  
Jorge Rodriguez
Keyword(s):  
Set Up ◽  

Author(s):  
D. A. Saravanos ◽  
C. C. Chamis

Abstract A method is developed for the optimal design of composite links based on dynamic performance criteria directly related to structural modal damping and dynamic stiffness. An integrated mechanics theory correlates structural composite damping to the parameters of basic composite material systems, laminate parameters, link shape, and modal deformations. The inclusion of modal properties allows the selective minimization of vibrations associated with specific modes. Ply angles and fiber volumes are tailored to obtain optimal combinations of damping and stiffness. Applications to simple composite links indicate wide margins for trade-offs and illustrate the importance of various design variables to the optimal design.


2009 ◽  
Vol 610-613 ◽  
pp. 85-96 ◽  
Author(s):  
Jing Dong Zhao ◽  
Shi Jun Su ◽  
Nan Shan Ai ◽  
Xiao Fan Zhu

A mathematical model for flue gas desulfurization using pyrolusite pulp in jet bubbling reactor (JBR) was described. Firstly, based on the concept of two stages mass balance with chemical reaction, two models were set up, for jet bubbling zone and rising bubble zone, respectively, according to the construction of JBR. The models consist of two coupling differential equations and were solved simultaneously by integral and separation of the variables. Then the SO2 absorption efficiency expression was developed, considering the great discrepancy existing between the gas-side mass transfer coefficients of the jet bubbling zone and gas bubble rising zone. The final expression associates SO2 absorption efficiency with process conditions and JBR structure parameters, which can give some instruction and guidance for the study of reactor operation process. Predicted results from the theoretical model, including effect of pH value of the pulp, flue gas temperature and inlet SO2 concentration of flue gas on SO2 absorption efficiency, were found to be in good agreement with experimental data obtained in a jet bubbling reactor. The model provides a basis for the process scale up and operating guide.


Author(s):  
B. Traipattanakul ◽  
C. Y. Tso ◽  
Christopher Y. H. Chao

Condensation of water vapor is an important process utilized in energy/thermal/fluid systems. When droplets coalesce on the non-wetting surface, excess surface energy converts to kinetic energy leading to self-propelled jumping of merged droplets. This coalescing-jumping-droplet condensation can better enhance heat transfer compared to classical dropwise condensation and filmwise condensation. However, the resistance force can cause droplets to return to the surface. These returning droplets can either coalesce with neighboring droplets and jump again, or adhere to the surface. As time passes, these adhering droplets can become larger leading to progressive flooding on the surface, limiting heat transfer performance. However, an electric field is known to be one of the effective methods to prevent droplet return and to address the progressive flooding issue. Therefore, in this study, an experiment is set up to investigate the effects of applied electrical voltages between two parallel copper plates on the jumping height with respect to the droplet radius and to determine the average charge of coalescing-jumping-droplets. Moreover, the gravitational force, the drag force, the inertia force and the electrostatic force as a function of the droplet radius are also discussed. The gap width of 7.5 mm and the electrical voltages of 50 V, 100 V and 150 V are experimentally investigated. Droplet motions are captured with a high-speed camera and analyzed in sequential frames. The results of the study show that the applied electrical voltage between the two plates can reduce the resistance force due to the droplet’s inertia and can increase the effects of the electrostatic force. This results in greater jumping heights and the jumping phenomenon of some bigger-sized droplets. With the same droplet radius, the greater the applied electrical voltage, the higher the coalescing droplet can jump. This work can be utilized in several applications such as self-cleaning, thermal diodes, anti-icing and condensation heat transfer enhancement.


Author(s):  
Ken Ueno ◽  
Michiaki Tatsubori

An enterprise service-oriented architecture is typically done with a messaging infrastructure called an Enterprise Service Bus (ESB). An ESB is a bus which delivers messages from service requesters to service providers. Since it sits between the service requesters and providers, it is not appropriate to use any of the existing capacity planning methodologies for servers, such as modeling, to estimate the capacity of an ESB. There are programs that run on an ESB called mediation modules. Their functionalities vary and depend on how people use the ESB. This creates difficulties for capacity planning and performance evaluation. This article proposes a capacity planning methodology and performance evaluation techniques for ESBs, to be used in the early stages of the system development life cycle. The authors actually run the ESB on a real machine while providing a pseudo-environment around it. In order to simplify setting up the environment we provide ultra-light service requestors and service providers for the ESB under test. They show that the proposed mock environment can be set up with practical hardware resources available at the time of hardware resource assessment. Our experimental results showed that the testing results with our mock environment correspond well with the results in the real environment.


Sensors ◽  
2019 ◽  
Vol 19 (2) ◽  
pp. 360 ◽  
Author(s):  
Guillaume Kock ◽  
Philippe Combette ◽  
Marwan Tedjini ◽  
Markus Schneider ◽  
Caroline Gauthier-Blum ◽  
...  

A new single-axis gas thermal gyroscope without proof mass is presented in this paper. The device was designed, manufactured and experimentally characterized. The obtained results were compared to numerical simulation. The working principle of the gyroscope is based on the deflection of a laminar gas flow caused by the Coriolis effect. A bidirectional hot air flow is generated by alternating activation of two suspended resistive micro-heaters. The heated gas is encapsulated in a semi-open cavity and the gas expands primarily inside the cavity. The thermal expansion gyroscope has a simple structure. Indeed, the device is composed of a micromachined cavity on which three bridges are suspended. The central bridge is electrically separated into two segments enabling to set up two heaters which may be supplied independently from each other. The two other bridges, placed symmetrically on each side of the central bridge, are equipped with temperature detectors which measure variations in gas temperature. The differential temperature depends on the rotational velocity applied to the system. Various parameters such as the heating duty cycle, the type of the gas and the power injected into the heaters have been studied to define the optimal working conditions required to obtain the highest level of sensitivity over a measurement range of around 1000°/s. The robustness of the device has also been tested and validated for a shock resistance of 10,000 g for a duration of 400 µs.


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