INVESTIGATING THE EFFECT OF SLOSHING ON THE ENERGY ABSORPTION OF TANK WAGONS CRASH

2015 ◽  
Vol 39 (2) ◽  
pp. 187-200 ◽  
Author(s):  
Reza Razaghi ◽  
Majid Sharavi ◽  
Mohammad Mahdi Feizi

One of the main fluid mechanics phenomena is fluid sloshing which is originated from the free surface of fluid and should be taken into account in design of fluid structures such as fuel tank wagons, ships and so on. The aim of this paper is to investigate the effect of tank fluid sloshing on energy absorption and reducing tank acceleration during the tank wagon impact. For this purpose, methods of software simulation and dynamics solution methods are accomplished. The assumed wagon includes a tank with the approximate volume of 95 m3 and capacity of 65 tons of fluid. Using finite element method, the tank impact is simulated based on the corresponding standards for different heights of fluid in the tank. Obtained results show fluid height increase has an inappropriate effect on energy absorption among impact however the more fluid in tank, the more time would be consumed for energy absorption in general. At the end, by using crash test results for a tank with aforementioned scale, validity of impact software simulation and dynamic solution method considering the tank fluid as mass-spring model are checked.

2021 ◽  
Vol 313 ◽  
pp. 08003
Author(s):  
Prastowo Murti ◽  
Akira Takizawa ◽  
Eita Shoji ◽  
Tetsushi Biwa

In a multi-cylinder type liquid piston Stirling engine (MCLPSE), liquid columns in U-shaped tubes play the role of solid pistons in a mechanical Stirling engine. Besides the straightforward structure, advantages of the MCLPSE are a relatively low operation temperature difference below 100 K and use of harmless working fluids of air and water. This study presents a mass spring model for the MCLPSE, from which we determine geometrical parameters of MCLPSE to achieve a target acoustic power production under a given temperature condition. The preliminary test results will be presented.


2021 ◽  
Vol 16 ◽  
pp. 155892502110125
Author(s):  
Sha Sha ◽  
Anqi Geng ◽  
Yuqin Gao ◽  
Bin Li ◽  
Xuewei Jiang ◽  
...  

There are different kinds of geometrical models and physical models used to simulate weft knitted fabrics nowadays, such as loop models based on Pierce, piecewise function, spline curve, mass-spring model, and finite element analyses (FEA). Weft knitting simulation technology, including modeling and yarn reality, has been widely adopted in fabric structure designing for the manufacturer. The technology has great potentials in both industries and dynamic virtual display. The present article is aimed to review the current development of 3-D simulation technique for weft knitted fabrics.


2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
Ying Tang ◽  
Dong-Yan Wu ◽  
Jing Fan

This paper proposes a computational approach to seasonal changes of living leaves by combining the geometric deformations and textural color changes. The geometric model of a leaf is generated by triangulating the scanned image of a leaf using an optimized mesh. The triangular mesh of the leaf is deformed by the improved mass-spring model, while the deformation is controlled by setting different mass values for the vertices on the leaf model. In order to adaptively control the deformation of different regions in the leaf, the mass values of vertices are set to be in proportion to the pixels' intensities of the corresponding user-specified grayscale mask map. The geometric deformations as well as the textural color changes of a leaf are used to simulate the seasonal changing process of leaves based on Markov chain model with different environmental parameters including temperature, humidness, and time. Experimental results show that the method successfully simulates the seasonal changes of leaves.


Author(s):  
Salina Sulaiman ◽  
Tan Sing Yee ◽  
Abdullah Bade

Physically based models assimilate organ-specific material properties, thus they are suitable in developing a surgical simulation. This study uses mass spring model (MSM) to represent the human liver because MSM is a discrete model that is potentially more realistic than the finite element model (FEM). For a high-end computer aided medical technology such as the surgical simulator, the most important issues are to fulfil the basic requirement of a surgical simulator. Novice and experienced surgeons use surgical simulator for surgery training and planning. Therefore, surgical simulation must provide a realistic and fast responding virtual environment. This study focuses on fulfilling the time complexity and realistic of the surgical simulator. In order to have a fast responding simulation, the choice of numerical integration method is crucial. This study shows that MATLAB ode45 is the fastest method compared to 2nd ordered Euler, MATLAB ode113, MATLAB ode23s and MATLAB ode23t. However, the major issue is human liver consists of soft tissues. In modelling a soft tissue model, we need to understand the mechanical response of soft tissues to surgical manipulation. Any interaction between haptic device and the liver model may causes large deformation and topology change in the soft tissue model. Thus, this study investigates and presents the effect of varying mass, damping, stiffness coefficient on the nonlinear liver mass spring model. MATLAB performs and shows simulation results for each of the experiment. Additionally, the observed optimal dataset of liver behaviour is applied in SOFA (Simulation Open Framework Architecture) to visualize the major effect.


1970 ◽  
Vol 24 (4) ◽  
pp. 295-304 ◽  
Author(s):  
Krešimir Grilec ◽  
Gojko Marić ◽  
Katica Miloš

The requirements for weight reduction and improvement of performances in the design of transport means are often in contradiction to the requirements for increased safety. One of the possible ways of meeting these requirements is the application of metal foams. Thanks to cellular structure of aluminium foam along with low weight, the capability of noise and vibration damping, they feature also excellent capabilities of absorbing impact energy. Their application in the production of impact-sensitive elements of mobile or stationary transport means has significantly contributed to the reduction of the impact or collision consequences.The focus of this paper is on improving the energy absorption characteristics of aluminium foams considering the significance of their application for the technology of traffic and transport.The paper analyzes the influence of the chemical composition and density on the compression behaviour of aluminium foam. The aluminium foam samples were produced from Alulight precursor. The capability of samples to absorb mechanical energy has been estimated according to the results of compression tests. The tests were performed on a universal test machine. The test results showed that aluminium foams feature good energy absorption and the absorption capability decreases with the foam density. The Alulight AlMgSi 0.6 TiH2 - 0.4 foam can absorb more energy than Alulight AlSi 10 TiH2 – 0.8 foam.


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