scholarly journals Research on Simulation Method of Missile Adapter’s Separation Based on Combined Calculation

2019 ◽  
Vol 2019 ◽  
pp. 1-9 ◽  
Author(s):  
Miao Chen ◽  
Yi Jiang ◽  
Shaoyan Shi ◽  
Wei Zeng
Keyword(s):  
Grid Method ◽  
Simulation Method ◽  
Separation Process ◽  
Force Analysis ◽  
Wind Speeds ◽  
Force And Motion ◽  
Aerodynamic Parameters ◽  
Simulation Results ◽  
Container Type ◽  
Good Agreement

In the background of a container-type vertical launch missile, the simulation method of adapter separation in different wind speeds is researched. Based on force analysis of the adapters during their separation from the missile, the dynamic and kinematics equations of the adapter separation are established. The adapter’s aerodynamic parameters at different attitudes getting from the numerical wind tunnel are chosen to be the input. Through the dynamic simulation of the separation process of the adapters, the simulation results are in good agreement with the experimental data. The trajectory and placement distribution of adapters are obtained during the analysis of force and motion stance at different wind speeds. Then the relative distances between the adapter and missile or launch facility are determined. At the same time, it can be estimated that the combined calculation will save about two-thirds of time compared with dynamic grid method computing, which provides a significant guidance for the simulation method of adapter separation.

Load Rejection Tests and Their Dynamic Simulations With a 150 kW Class Microsteam Turbine

2013 ◽  
Vol 135 (5) ◽  
Author(s):  
Susumu Nakano ◽  
Kuniyoshi Tsubouchi ◽  
Hiroyuki Shiraiwa ◽  
Kazutaka Hayashi ◽  
Hiroyuki Yamada
Keyword(s):  
Dynamic Simulation ◽  
Rotational Speed ◽  
Delay Time ◽  
Simulation Method ◽  
Dynamic Simulations ◽  
Machine Reliability ◽  
Delay Times ◽  
Simulation Results ◽  
Generator Output ◽  
Good Agreement

A simulation method for load rejection with a 150 kW class radial inflow steam turbine system was proposed to determine over rotational speed at load rejection. Simulations were carried out for several parameters of valves which are operated in an emergency. In addition, load rejection tests were carried out to confirm the machine reliability and to obtain results for comparison with the simulation results. Simulation results show that operation delay times of the steam release and vacuum break valves greatly affect over rotational speed at load rejection. Load rejection tests were done for generator outputs from 69 kW to 113 kW. Maximum over rotational speed of 54,160 rpm was measured at the generator output of 113 kW. Over rotational speed calculated by the dynamic simulation has relatively good agreement with the result for the operation delay time of 0.21 s. If the operation delay time of the steam release valves are kept as 0.21 s at the load rejection for the rated load of 150 kW, the over rotational speed is suppressed within 55,200 rpm which is less than the allowed rotational speed of 56,100 rpm.

Optimization of geometrical design of clinching tools in clinching process with extensible dies

2016 ◽  
Vol 231 (21) ◽  
pp. 3889-3897 ◽  
Author(s):  
Xiaolan Han ◽  
Shengdun Zhao ◽  
Chen Liu ◽  
Chao Chen ◽  
Fan Xu
Keyword(s):  
Experimental Design ◽  
Simulation Model ◽  
Simulation Method ◽  
Orthogonal Experimental Design ◽  
Optimal Parameters ◽  
Geometrical Design ◽  
Reasonable Range ◽  
Simulation Results ◽  
Sliding Distance ◽  
Good Agreement

Due to the importance of geometrical design of clinching tools, the clinching process with extensible dies was investigated numerically and experimentally to seek for optimal parameters of clinching tools in this study. The joining parameters, including punch corner radius, sliding distance, die depth and bottom thickness, were optimized using the orthogonal experimental design simulation method based on the evaluation of tensile strength. The simulation results were validated through an experimental setup testing on material aluminum alloy Al5052. The orthogonal experimental design simulation results showed reasonably good agreement with the experimental results. To further investigate the validation of the simulation model, the different bottom thicknesses within a reasonable range of value were studied. The results also indicated that the simulation model could be employed to predict the joint forming by the clinching process with extensible dies.

A Brownian Dynamics Model of Worm-Like-Biomolecule Separation Using Periodic Nanofilter Arrays

2009 ◽  
Author(s):  
Ghassan N. Fayad ◽  
Nicolas G. Hadjiconstantinou
Keyword(s):  
Theoretical Model ◽  
Theoretical Prediction ◽  
Brownian Dynamics ◽  
Separation Process ◽  
Dynamics Model ◽  
Dsdna Molecule ◽  
Biomolecule Separation ◽  
Simulation Results ◽  
Asymmetric Device ◽  
Good Agreement

We present a Brownian Dynamics model of dsDNA-molecule separation using periodic nanofilter arrays. Particular attention is paid to the model’s ability to capture relevant experimental results. The effect of various device parameters on molecule selectivity is investigated. Moreover, our model is used for validating the theoretical prediction of Li et al. [Anal. Bioanal. Chem., 394, 427–435, 2009] who proposed a separation process featuring an asymmetric device and an electric field of alternating polarity. Good agreement is found between our simulation results and the predictions of the theoretical model of Li et al.

Development of Ink-Particle Flight Simulation for Continuous Inkjet Printer

2013 ◽  
Author(s):  
Masato Ikegawa ◽  
Eiji Ishii ◽  
Nobuhiro Harada ◽  
Tsuneaki Takagishi
Keyword(s):  
High Speed ◽  
Fluid Dynamic ◽  
Electrostatic Force ◽  
Simulation Method ◽  
Flight Simulation ◽  
Analysis Software ◽  
Continuous Type ◽  
Inkjet Printers ◽  
Simulation Results ◽  
Good Agreement

An ink-particle flight simulation method for industrial, continuous-type inkjet printers was developed to clarify the factors that influence the print distortion. Print distortion is produced by aerodynamic and electric interference between the ink-particles flying from the nozzle onto the print-target. The necessary functions to do this, such as the calculation of electrostatic force in the electric field between the electrodes, the Coulomb’s force from other charged ink-particles, and the drag force in the inkjet stream for many flying ink-particles were added to a Lagrangian method in the fluid dynamic analysis software that was used for the simulation. The trajectories of the ink-particles flying from this nozzle onto the print target and the air-flow caused by them were calculated simultaneously in the simulation. The simulation results for the velocities and trajectories of the flying ink-particles were compared with the experimental ones using a high-speed camera. These simulation results were in good agreement with the experimental ones, and this helps to clarify the factors that influence the print distortion.

Simulation of sliver blending and evaluation of blending irregularity

2021 ◽  
pp. 004051752110288
Author(s):  
Qiaoli Cao ◽  
Lili Qian ◽  
Hao Li ◽  
Chongwen Yu
Keyword(s):  
Simulation Method ◽  
Research Results ◽  
Blended Yarn ◽  
Blending Process ◽  
Fiber Components ◽  
Simulation Results ◽  
Experiment And Simulation ◽  
Good Agreement

The quality of blended yarn depends on the uniformity of the blending of the multi-component fibers in the yarn, and sliver blending is a process necessary for mixing fibers. The movement of fibers directly affects the distribution and mixing of fibers in the sliver. In this paper, the sliver blending process was simulated, and a method for the evaluation of sliver blending irregularity was proposed. The effects of passages of drawing and blending ratio on the sliver mixing uniformity were studied and verified both by experiment and simulation. The results show that the blending irregularity decreases gradually and tends to be stable with the increase of the passages of blending drawing. The more similar the blending ratio of the two components with approximately equal linear densities, the easier it is for the component fibers to mix evenly in the sliver. The simulation results are in good agreement with the measured values and previous research results. In addition, the blending irregularity of fiber components in the blended sliver can be predicted by the simulation method.

Study on Mechanics Properties of Shifting Impact of Overrunning AMT

2012 ◽  
Vol 252 ◽  
pp. 134-139
Author(s):  
Jian Jun Hao ◽  
Shuai Shuai Ge ◽  
Xi Hong Zou ◽  
Xiao Hui Ding
Keyword(s):  
Mathematical Model ◽  
Computer Simulation ◽  
Dynamic Model ◽  
Structural Characteristics ◽  
Transmission System ◽  
Separation Process ◽  
Force Analysis ◽  
Long Time ◽  
Simulation Results ◽  
The Mathematical Model

Aiming at the problem of long time power interruption and clutch master-slave friction plates wore seriously which greatly shorten the life of clutch during shifting process of AMT, a overrunning AMT without separation process of clutch when shifting is designed. This paper has analyzed structural characteristics and shift principle of overrunning AMT. Through force analysis on the jointing process of roller overrunning clutch, the mathematical model and dynamic model of transmission system are established. Finally, the shifting impact of shifting process is analyzed based on computer simulation. The simulation results indicate that vehicle longitudinal degree of jerk meets the requirement of vehicle comfort.

An Analysis on Dynamic Damage on Concrete Obstruct Subjected to Underwater Explosion Shock Waves

2006 ◽  
Vol 306-308 ◽  
pp. 1373-1378
Author(s):  
Li Hao ◽  
Jian Guo Ning
Keyword(s):  
Shock Waves ◽  
Underwater Explosion ◽  
Simulation Method ◽  
C Language ◽  
Damage Degree ◽  
Simulation Results ◽  
The Given ◽  
Dynamic Damage ◽  
Optimum Charge ◽  
Good Agreement

Based on the multi-material Eulerian algorithm, the damage effects of concrete obstruct subjected to underwater explosion shock waves are simulated by using the NM-MMIC code which is a 2D multi-material elastic-plastic hydrodynamics code with C++ language. According to the simulation results of underwater explosion, the optimum charge, the damage degree and the damage laws of obstruct are obtained. The simulation results show a good agreement with that obtained by DYNA2D. Thus the given study indicates that the model and algorithm presented in this paper are reasonable and the simulation method can be used for designing and estimating ammunitions against obstructs in water.

Three-Dimensional Numerical Simulation of the Hydraulic Characteristics of Spillway in Gushitan Reservoir

2012 ◽  
Vol 256-259 ◽  
pp. 2403-2406
Author(s):  
Shu Guang Jing ◽  
Xue Ping Gao ◽  
Lai Fei Jia ◽  
Li Ping Xu
Keyword(s):  
Numerical Simulation ◽  
Water Surface ◽  
Three Dimensional ◽  
Simulation Method ◽  
Vof Method ◽  
Hydraulic Characteristics ◽  
Bottom Pressure ◽  
Surface Profiles ◽  
Simulation Results ◽  
Good Agreement

Based on standard k-ε turbulence model and the VOF method for tracking free surface, hydraulic characteristics of the spillway in Gushitan Reservoir are simulated with a 3-D numerical model. The discharge capacity, water surface profiles, bottom pressure distribution and flow pattern are studied. Numerical simulation results have been in good agreement with experimental results, showing fine feasibility to study hydraulic characteristics of the spillway with the VOF method. The hydraulic characteristics acquired by the numerical simulation method can be used for spillway design.

Evaluations of Absorption Materials Applied in the Noise Reduction: Experiment and Simulation

2019 ◽  
Vol 947 ◽  
pp. 125-129
Author(s):  
Y.C. Liu ◽  
Y.C. Huang ◽  
Yun Jhe Tang ◽  
Tzu Hsuan Lei
Keyword(s):  
Finite Element ◽  
Simulation Method ◽  
Comsol Multiphysics ◽  
Airflow Resistance ◽  
Finite Element Software ◽  
Reduction Experiment ◽  
Multiphysics Simulations ◽  
Element Simulation ◽  
Simulation Results ◽  
Good Agreement

This article presents a finite element simulation method for airflow resistance of material to predict the influence of absorption material applied to compressor box. To obtain the real airflow resistance, a measurement system based on the standard ASTM C522-03 was systematically built up and carefully verified. Furthermore, commercial finite element software, COMSOL Multiphysics, was adopted to create the model and execute the simulation with and without absorption material. Results showed that airflow resistance increases with the thickness and the density of the material. This system is quite stable and suited to any material. With the aid of COMSOL Multiphysics simulations, the performance of noise with and without absorption material can be analyzed and compared with experimental results. There was good agreement between experimental and simulation results. Based on absorption material of 15,278 Pa.s/m3 airflow resistance, the noise level outside the compressor box obtained from experiment was around 10 dBA higher than that obtained from simulation.

scholarly journals Study on Galloping Oscillation of Iced Twin Bundle Conductors considering the Effects of Variation of Aerodynamic and Electromagnetic Forces

2020 ◽  
Vol 2020 ◽  
pp. 1-18
Author(s):  
Chuan Wu ◽  
Zhongfei Ye ◽  
Bo Zhang ◽  
Yong Pan ◽  
Qing Li ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
Relative Motion ◽  
Electromagnetic Force ◽  
Simulation Method ◽  
Aerodynamic Forces ◽  
Mode Amplitude ◽  
Two Factors ◽  
Time Histories ◽  
Aerodynamic Parameters ◽  
Simulation Results

Due to the occurrence of whole-span and subspan vibration at the same time during the galloping of the iced bundle conductors, the distance between the subconductors changes, resulting in the variation of the aerodynamic parameters for the leeward subconductors. The existing conventional studies usually only consider the whole-span galloping, ignoring the relative motion and the electromagnetic force between the subconductors. Based on considering the above two factors at the same time, a new numerical simulation method to study the galloping behaviors of the iced conductors is presented. Then, the galloping behaviors of the iced twin bundle conductors’ transmission line with different current intensity, initial wind attack angle, and spacer layout are studied. The galloping oscillation behaviors include time histories of vibration displacements, mode, amplitude, frequency, motion traces, and the distance between two subconductors. The simulation results showed that the whole-span and subspan vibration appear at the same time during galloping oscillation and two subconductors may collide with each other when affected by the varying electromagnetic and aerodynamic forces. The effects of varying electromagnetic and aerodynamic forces on galloping behavior cannot be ignored. The new method presented in this work can contribute to the galloping study of the iced bundle conductors.

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