scholarly journals Fluid Dynamic Response of the Russia Seismically Differing Regions to the Global Geodynamics Processes

2012 ◽  
Vol 03 (04) ◽  
pp. 767-771 ◽  
Author(s):  
Valera P. Rudakov ◽  
Pavel P. Firstov ◽  
Vladislav V. Tsyplakov
Keyword(s):  
Dynamic Response ◽  
Fluid Dynamic ◽  
Global Geodynamics

The Role of Simulation in the Development of a Fast-Actuation Solenoid C.R. Injection System

2004 ◽  
Author(s):  
Gian Marco Bianchi ◽  
Piero Pelloni ◽  
Giovanni Osbat ◽  
Marco Parotto ◽  
Rita Di Gioia ◽  
...  
Keyword(s):  
Dynamic Response ◽  
Control Strategies ◽  
Fluid Dynamic ◽  
Numerical Approach ◽  
Linear Analysis ◽  
Operating Conditions ◽  
System Model ◽  
Injection System ◽  
Multiple Injection ◽  
Pressure Regulator

Upcoming Euro 4 and Euro 5 emission standards are increasing efforts on injection system developments in order to improve mixture quality and combustion efficiency. The target features of advanced injection system are related to their capability of operating multiple injection with a precise control of amount of fuel injected, low cycle-by-cycle variability and life drift, within flexible strategies. In order to accomplish this task, performance must be optimised since injection system concept development by acting on. The extensive use of numerical approach has been identified as a necessary integration to experiments in order to put on the market high quality injection system accomplishing strict engine control strategies. The modelling approach allows focusing the experimental campaign only on critical issues saving time and costs, furthermore it is possible to deeply understand inner phenomena that cannot be measured. The lump/ID model of the whole system built into the AMESim® code was presented in previous works: particular attention was devoted in the simulation of the electromagnetic circuits, actual fluid-dynamic forces acting on needle surfaces and discharge coefficients, evaluated by means 3D-CFD simulations. In order to assess new injection system dynamic response under multiple injection strategies reproducing actual engine operating conditions it is necessary to find to proper model settings. In this work the integration between the injector and the system model, which comprehends the pump, the pressure regulator, the rail and the connecting-pipes, will be presented. For reproducing the dynamic response of he whole system will be followed a step-by-step approach in order to prevent modelling inaccuracies. Firstly will be presented the linear analysis results performed in order to find injection system own natural frequencies. Secondly based on linear analysis results will be found proper injection system model settings for predicting dynamic response to external excitations, such as pump perturbations, pressure regulator dynamics and injection pulses. Thirdly experimental results in terms of instantaneous flow rate and integrated injected volume for different operating conditions will be presented in order to highlight the capability of the modelling methodology in addressing the new injection system design.

Effect of Baffle Design Parameters on Fluid Dynamic Response of a Coal Classifier

2014 ◽  
Vol 3 (0) ◽  
pp. 15
Author(s):  
Hamid Khoshdast ◽  
Hami Khoshdast ◽  
Vahideh Shojaei
Keyword(s):  
Dynamic Response ◽  
Fluid Dynamic ◽  
Design Parameters

Development of a coupled numerical model for the interaction between transient fluid slosh and tank wagon vibration

2018 ◽  
Vol 233 (3) ◽  
pp. 568-582 ◽  
Author(s):  
Ahmad Rahmati-Alaei ◽  
Majid Sharavi ◽  
Masoud Samadian Zakaria
Keyword(s):  
Dynamic Response ◽  
Stokes Equations ◽  
Fluid Dynamic ◽  
Nonlinear Differential Equations ◽  
Coupled Model ◽  
Longitudinal Direction ◽  
Rolling Contact ◽  
Cross Sectional ◽  
Response Characteristics ◽  
Dynamic Response Characteristics

In this paper, a coupled model is developed to evaluate the effect of transient fluid slosh on the railway tank wagon dynamic vice versa. This model has computational complexity in solving the Navier–Stokes equations and nonlinear differential equations of tank wagon vibration with nonlinear wheel–rail contact. The coupled model can be used as an effective and robust tool compared to simplified models for assessing the stability of tank wagon. The transient fluid slosh model is analysed using the computational fluid dynamic method combined with the volume of fluid technique. The tank wagon dynamic model is solved using the fourth-order Runge–Kutta method based on the 19 degrees of freedom model with longitudinal, vertical, roll and pitch vibrations. The wheel–rail contact is considered according to nonlinear Hertzian and Kalker linear rolling contact theories. The fluid slosh model is validated using experimental data. The dynamic response characteristics of the partially filled railway tank wagon are investigated under straight-line braking manoeuvre using the coupled model. The results obtained from a parametric study, including the cross sectional shape and the filled volume show that the modified-oval cross section improves the dynamic response characteristics, which are attributed to its lower fluid's centre of gravity coordinate in the longitudinal direction and low lateral moment transfer of the fluid.

scholarly journals Train-Induced Fluctuating Pressure and Resultant Dynamic Response of Semienclosed Sound Barriers

2020 ◽  
Vol 2020 ◽  
pp. 1-16
Author(s):  
Jing Zheng ◽  
Qingliang Li ◽  
Xiaozhen Li ◽  
Yunke Luo
Keyword(s):  
Dynamic Response ◽  
Time Pressure ◽  
Fluid Dynamic ◽  
Vibration Measurement ◽  
Fe Model ◽  
Length Effect ◽  
Fluctuating Pressure ◽  
Sound Barriers ◽  
First Time

This paper reports on train-induced fluctuating pressure and consequent dynamic response of semienclosed sound barriers (SESBs), a novel type of sound barriers. A computational fluid dynamic (CFD) model and a finite element (FE) model were established. The in situ vibration measurement of the SESB was introduced for the first time. Pressure-induced vibrations were extracted from the measured results. The analyzing process of the pressure-induced vibration below 20 Hz is verified. Influencing factors of the pressure and vibrations, including train running on the near- or far-line and the length effect of total top plates, were finally discussed with the dimensionless method. Results show that the distribution of pressure is significantly different, but the vibration laws are similar whether the train is running on the near- or far-line. The longer is the total length of the top plates, the larger are the pressure and vibration on the inner surface.

scholarly journals A Generalized Reduced Fluid Dynamic Model for Flow Fields and Electrodes in Redox Flow Batteries

2021 ◽  
Author(s):  
Ziqiang Cheng ◽  
Kevin Tenny ◽  
Alberto Pizzolato ◽  
Antoni Forner-Cuenca ◽  
Vittorio Verda ◽  
...  
Keyword(s):  
Dynamic Response ◽  
Fluid Dynamic ◽  
Fluid Motion ◽  
Maximum Velocity ◽  
Flow Fields ◽  
Three Dimensions ◽  
Modeling Framework ◽  
Plane Flow ◽  
Computational Overhead ◽  
2D Model

High dimensional models typically require a large computational overhead for multiphysics applications, which hamper their use for broad-sweeping domain interrogation. Herein, we develop a modeling framework to capture the through-plane fluid dynamic response of electrodes and flow fields in a redox flow cell, generating a computationally inexpensive two-dimensional (2D) model. We leverage a depth averaging approach that also accounts for variations in out-of-plane fluid motion and departures from Darcy’s law that arise from averaging across three-dimensions (3D). Our Resulting depth-averaged 2D model successfully predict the fluid dynamic response of arbitrary in-plane flow field geometries, with discrepancies of < 5% for both maximum velocity and pressure drop. This corresponds to reduced computational expense, as compared to 3D representations (< 1% of duration and 10% of RAM usage), providing a platform to screen and optimize a diverse set of cell geometries.

Human pilot dynamic response in flight and simulator.

1958 ◽  
Author(s):  
Edward Seckel ◽  
Ian A. M. Hall ◽  
Duane T. McRuer ◽  
David H. Weir
Keyword(s):  
Dynamic Response
Sign in / Sign up

Export Citation Format

Share Document