Showing 6 results for Composite
N. Tavassoli, A. Darvizeh, M. Darvizeh,
Volume 2, Issue 1 (1-2012)
Abstract
Car body lightening and crashworthiness are two important objectives of car design. Due to their excellent performance, composite materials are extensively used in the car industries. In addition, reducing the weight of vehicle is effective in decreasing the fuel consumption. Hat shape energy absorber is used in car’s doors for side impact protection.
The aim of these numerical models and experimental tests is to unveil some important fact about using composite materials in hat shape energy absorber and also show the effect of orientation angles on the amount of energy absorption. The effects of different orientation angles on crushing behavior of hat shape structure are presented.
M. Mokhtari, K. Farhadi,
Volume 4, Issue 1 (3-2014)
Abstract
Automobile light weight structural composites are subjected to the various loadings in their service lives. Honeycombs are increasingly used as core structures in automobile light weight structures as energy absorbers. In this paper the energy absorption of honeycomb panels under impact of cylindrical projectile is numerically and experimentally studied. The effect of the core materials and cross-ply or semi-isotropic lamination of face-sheets are checked numerically. Results shown that the aluminum cores vs. Nomex cores and semi-isotropic lamination of face-sheets have much better energy absorption aspects in impact loading.
A. Khalkhali, M. Afroosheh, M.r. Seyedi,
Volume 4, Issue 1 (3-2014)
Abstract
In this paper, numerical simulation of FRP composite cylinder tubes progressive crushing processes is conducted using LS-Dyna. Details on the numerical modeling strategy are given and discussed. It is found that triggers introduced in the numerical simulation can effectively model the bevel trigger at the end of the tubular specimens. It is also found that two-layer finite element model based on the TsaiWu failure criteria is effective in representing the crushing failure mode of the tubular composite specimens and energy absorption characteristics. Employing GEvoM software, two meta-models are then obtained for modeling of both the absorbed energy (E) and the peak crushing force (Fmax) with respect to geometrical design variables using input output data obtained from the finite element modeling. Comparison between obtained meta-models and numerical results in both of training and testing sets show good approximation by using obtained polynomial models.
Mustafa Mirtabaee, Mohammad Abasi,
Volume 13, Issue 4 (12-2023)
Abstract
Protection of Armor Vehicles and military truck Occupants Against Explosion Mine and IED is the most important Parameter for comprehensive performance evaluation of armored vehicle. Armored Vehicle components Specifically Hull Floor Must be Able to Disperse Blast Shock Waves and Resist Against the structural Fracture. Analysis of the War Documents proves that flat hulls with thin-walled steel cannot resist against Anti-Tank Mines. In Recent years, development of V-shape Hull configurations Consider as an efficient Approach to improve Safety of armored vehicles. In the new generation of Armor Vehicle, Monocoque chassis combined with V-shape hull, But Replacement of All of the Old Armor Vehicle in the Defense Industry is not cost effective. So, there is an urgent need to develop the efficient strategy for enhancing the protection level of old armor vehicle. Since most of the armored vehicles used in the armies of different countries were designed and built in the past years, it is very likely that the safety standards have not been fully observed in them. Therefore, it is of great importance to provide a simple and low-cost plan for the reliable upgrade of such armored and logistics vehicles. In this article, by investigating the effect of placing V-shaped composite panels in three case studies, we were able to reduce the acceleration of the center of mass of the passenger compartment by approximately 7 times, in addition to reducing displacement by 50% on average. In addition, the explosion products were not able to penetrate into the cabin.
Mr. Nasrollah Taghizadeh, Dr. Mohsen Esfahanian,
Volume 14, Issue 1 (3-2024)
Abstract
Due to the importance of vehicle weight reduction which can reduce fuel consumption and air pollution, changes are made in vehicles. In heavy trucks with payload limitations, a lighter trailer can provide higher load-carrying capacity and more economical benefits. Composite materials are a good candidate for material exchange due to their resistance to various conditions and low weight compared to steel. In this paper, the trailer material made of steel will be replaced by composite so that strength density will remain the same. For this purpose, the finite element method is used for static and dynamic analyses. At first, the model of a two-axle trailer is developed using SolidWorks software. Then, using standard loading and failure theories (Tsai-Hill, Tsai-Wu), the number of composite layers and their suitable angles are selected for the chassis. Finally, the loaded trailer's static, modal, and dynamic analysis are performed using the finite element method with a composite material. Results show that 17 layers of polymer composite with glass fibers with 0-0 angle can reduce 17.7 percent weight.
Dr Mohammad Shirzadifar, Dr Javad Marzbanrad,
Volume 14, Issue 1 (3-2024)
Abstract
The corrugated composite plates have wide application to improve the energy absorption and failure behavior of panel structures. The roof panel of the bus could benefit from the use of these structures to reduce impact failures in rollover accidents. The aim of this paper is to design a new configuration of bus roof panels stiffened with multi-layer semi-circular corrugated CFRP plates to minimize structure failure during rollover accidents. An analytical failure equation of Tsai-Hill index for the new proposed panel subjected to dynamic impact loading has been derived. The failure equation was validated using FEM methods and digital image correlation impact tests. According to the roll over impact situation, the multi-layered semi-circular corrugated woven CFRP roof panel displays a positive failure behavior of 89%.
