Composite Carbody Research Articles

GEARBODIES - Innovative Technologies for Inspecting Carbodies and for Development of Running Gear

This work presents the progress of the ongoing Shift2Rail project GEARBODIES. The project has designed an inspection platform for the inspection of composite carbody shell, integrating thermography and ultrasonic equipment. GEARBODIES has also selected the two elastomer-metal components to be prototyped, a bushing in swingarm and a conical spring in primary suspension. Both components will be improved employing carbon nanotubes in the elastomer formulation. The last groups of innovations explored are focused on the journal bearings. To improve roller-race materials, a first selection of four potential High Entropy Alloys candidates have been selected. Regarding lubricants, it has been identified that working on housing solutions are more promising that working on bearing sealing solutions. The first test on polymers for cages have been also performed as well as potential modifications on the geometry of the bearing components. The presented results will be further researched and the conclusions published in future works.

ANALYSIS OF COMPOSITE ELECTRIC VEHICLE BODY

<p>This paper presents a study of a composite car body using finite element method. The body is made of surface model and the study is conducted to simulate the possible deformation of the body under certain load. The objective is to find tha ideal thickness of the composite body as to minimize the vehicle weight. In this research, the strength analysis using finite elements will be explained and the deformation of the body is investigated for finding a possibility to improve this research.</p>

경량 복합재 차체 구조의 역설계를 통한 복합재료 라미나 물성

경량 복합재 차체 구조의 역설계를 통한 복합재료 라미나 물성

Cost‐effective manufacturing process for the development of automotive from energy efficient composite materials and sandwich structures

The advanced composite materials are increasingly being used in the automotives for their ultralight physical properties and super strong mechanical properties. This research examines the cost‐effective single‐step liquid resin infusion manufacturing process for developing all composite car body as the generally used sheet molding compound manufacturing process is highly capital intensive. Three different scaled down models of the Eco car were developed focusing on minimal weight and air drag coupled with aesthetics. Structural design and analysis was carried out using the Pro/E and Ansys tools. The Pro‐E model was scaled up to generate computer‐aided drafting drawings for tool development. Different stations were marked on the model and sliced virtually for development of pattern. Moreover, the mold was manufactured from carbon and glass/polyester composites for prototype manufacturing of the car body. This involved manual placement of desired number of carbon layers as preform on female side of the mold. The vacuum sucked the resin through a number of carefully selected entry ports which ensured effective resin distribution and impregnation. Polycarbonate wind shield was thermoformed in the convection oven according to streamlined geometry of car body and hinged. The car body was integrated with the compatible floor panels and accessories. The crumble zone shock absorber in the bumper was manufactured using successive layers of nomax honeycomb and polyvinyl chloride rigid foam to dampen the accidental shock. The car performed remarkably well in the Eco marathon race held at Malaysia, 35:97–104, 2014. POLYM. COMPOS., 2013. © 2013 Society of Plastics Engineers

A NEW APPROACH TO DAMAGE DETECTION IN COMPOSITE BODY STRUCTURES USING TIME COMPENSATED HYPERSPECTRAL IMAGE ANALYSIS TECHNIQUE

A novel approach to damage detection in composite car body structures using hyperspectral image index analysis algorithm is presented and discussed. The adapted technique allows the monitoring and analysi s of a components structure based on correlation between time spaced thermal images. The technique produces several organized tables resulting from image fusio n and frame deviation pixel redistribution calculat ions, which results in computable matrices. The obtained results proved the technique to be capable of classifying damage with ability to model various ty pes of damage under various conditions. There is a need to accurately identify damaged composite components. This will enable the used algorithm to determine if the level of damage or defect in the component is c ritical according to established database that take s into account mechanical and physical factors. Testing di fferent composite structures using Hyperspectral technique and Pulse Video Thermography (PVT), as hyperspectral uses different bands with different wavelengths to analyze the image results, which ena bles better recognition and classification. Success ful recognition and component classification obtained with characterization of tested composite.

Numerical study on crashworthiness assessment and improvement of composite carbody structures of tilting train using hybrid finite element model

This paper describes the numerical results on crashworthiness assessment and improvement scheme of tilting train made of composite materials. The bodyshell of tilting train was composed of aluminum honeycomb sandwich panels and carbon-fabric/epoxy laminate composites. The input parameters for numerical analysis were obtained from material tests. Crashworthiness analysis of the tilting train was conducted using the explicit finite element analysis code LS-DYNA3D and according to four collision scenarios of the Korean railway safety rule. The hybrid finite element modeling technique, which is made up of 2D shell and 3D solid elements for three cars in the front and 1D equivalent element for the rest cars in the rear, was introduced to ensure fast and accurate design verification for crashworthiness of railway vehicle. The numerical results showed that hybrid modeling technique was an economical approach for the analyzed results, finite element modeling, and calculating time in comparison with conventional modeling method using 2D shell and 3D solid elements for railway vehicles.

Dynamic Characteristics of Composite Materials Body for Bi-Modal Tram

The car body of the bi-modal tram has been designed and built to have low floor to provide the old and the handicapped with easy access considering Korean physical standard, passenger capacity (standee, seated, handicapped), and bus and urban railway regulations in Korea. The car body has been composed of composite materials (light-weight sandwich constructions) with glass epoxy skins, aluminum honeycomb cores and aluminum inner-frames. This paper was aimed to evaluate dynamic characteristics of the car body while the bi-modal tram was running in the test track. Based on the results from vibration accelerations measured on the floor level of centers of car bodies and axle, dynamic characteristics of the composite materials car body were discussed in this paper.

Carbon composite car body panels gain traction with Gurit Automotive

Composite materials and technologies group Gurit AG has sired an automotive company to focus on developing and producing carbon fibre reinforced plastic body panels for prestige cars. George Marsh reports.

The suggestion of the standardized finite element model through the experimental verifications of various railway vehicle structures made of sandwich composites

In this study, a standardized finite element model for the carbody structures of various railway vehicles made of sandwich composites was suggested. The standardized finite element model for composite carbody structures was introduced and proposed by comparing the results of real structural tests under vertical, compressive, twisting load and natural frequency tests of various railway vehicles. The results showed that the quadratic shell element was suitable to model the reinforced metal frame used to improve the flexural stiffness of sandwich panels compared to beam elements, and layered shells and solid elements were recommended to model the skin and honeycomb core of sandwich panels compared to sandwich shell elements. Also, the proposed standard finite element model has the merit of being applied to crashworthiness analysis just by minor modifications, such as contact conditions and constraint equations.

A health management algorithm for composite train carbody based on FEM/FBG hybrid method

In this study, a health management program for a composite train carbody was developed using the acquired strain distributions from fiber Bragg grating (FBG) sensor arrays. To determine appropriate locations for the FBG sensors, a finite element analysis (FEA) was executed. In this FEA, a FE model of the Korean tilting train (TTX) was used as a representative composite carbody train. The FEA results of various derailment situations and high speed operation on curved track were used as the database of each deformation case. In the last step, the health management program was produced using LabVIEW software. In this post-processing algorithm, the method of least squares was used to determine the difference between the FEA results and the acquired strains. This program shows the estimated deformations and plots of the acquired strains, as well as displaying an emergency indicator when necessary, all through post-processing of the strains. Finally, this FEM/FBG hybrid method was verified by several simulations using the reproductive sensor data.

Fire resistance evaluation of a train carbody made of composite material by large scale tests

This paper explains fire resistance tests of a train carbody made of composite materials. In this study, fire performance tests using specimens and a large scale mock-up were performed to evaluate the fire safety of the composite train carbody. From the specimen tests, it was seen that the interior panels met the fire safety for the flame propagation, toxicity and smoke density performance. In addition, the fire resistance of the composites carbody was verified by the larger scale tests under the real fire accident scenario. From the results, both the surface temperature of the interior and the composite carbody were lower than the ignition temperature.

Structural Safety Evaluation of the Hybrid Composite Bodyshell for Korean Tilting Train by a Whole Body Test

This paper explains the structural safety evaluation of a hybrid composite train carbody. The composite carbody with length of 23m was manufactured as a sandwich structure composed of a 40mm-thick aluminum honeycomb core and 5mm-thick woven fabric CF1263 carbon/epoxy face. In order to evaluate the structural safety of it, the dynamic force of ±0.2g was applied to the full weight carbody by two 50-ton capacity hydraulic actuators. The excitation frequency was determined by the first bending natural frequency evaluation test under full weight condition. The test was conducted for 2x106cycles. During the test, the nondestructive tests using X-ray for the composite body structure and liquid penetrant test for the welding region of the steel underframe were performed.

Numerical and experimental studies on the deformational behavior a composite train carbody of the Korean tilting train

In this study, the vertical deflection and sectional deformation of the composite carbody were investigated by finite element analyses and experiments. The vertical and sectional deformations were measured using displacement gauges under the full weight load condition. The maximum deflection measured on the bottom of sidesill was 9.25 mm. The maximum deflection calculated from the finite element analysis was 8.28 mm. The analysis result was in agreement with the measured one within an error of 10.5%. In the cross-sectional deformation, the side wall was deformed inside of the carbody and the roof and under frame outside. The cross-sectional deformation of the composite carbody was compared with the E653 train of Japan Rail east. The deformational patterns were similar to each other.

복합재 철도차량 차체 고유진동수에 대한 해석 및 시험적 연구

This paper explains analytical and experimental studies to evaluate the natural frequency of a composite carbody of Korean tilting train. The composite carbody with length of 23m was manufactured as a sandwich structure composed of 40㎜-thick aluminium honeycomb core and 5㎜-thick woven fabric carbon/epoxy face. From the finite element analysis, the 1st bending and 1st twisting natural frequency of the composite carbody were 11.67㎐ and 14.4㎐, respectively. In order to verify the analytical results, the natural frequency measuring tests were performed. The measured 1st bending and twisting natural frequencies of the composite carbody were 10.25㎐ and 11.0㎐, respectively. Both of these results satisfied the design requirement.

Natural frequency evaluation of a composite train carbody with length of 23 m

This paper explains numerical and experimental studies to evaluate the natural frequencies of a composite carbody of the Korean tilting train. The composite carbody with a length of 23 m was manufactured as a sandwich structure composed of 40-mm thick aluminum honeycomb core and 5-mm thick woven fabric carbon/epoxy face. From the finite element analysis, the composite carbody had a first bending natural frequency of 11.67 Hz and a first torsional natural frequency of 14.4 Hz. In order to verify the numerical results, the natural frequency measuring tests were performed. The measured first bending and torsional natural frequencies of the composite carbody were 10.25 and 11.0 Hz, respectively. Both of these results satisfied the design requirement.

Manufacturing and structural safety evaluation of a composite train carbody

This paper explains the manufacturing process of a composite train carbody with a sandwich composite structure for bodyshell and a stainless steel structure for the under frame. In addition, the structural behavior and safety of the composite carbody of the Korean tilting train was investigated by the static load tests. From the test results, the stiffness of the composite carbody met the specified design. In the aspect of strength, the maximum stress of the composite bodyshell was of 12.2% of strength of CF1263 carbon/epoxy.

오토클레이브 성형된 길이 23m 복합재 철도차량 차체의 구조적 특성평가

This paper explains manufacturing process and experimental studies on a composite carbody of Korean tilting train. The composite carbody with length of 23m was manufactured as a sandwich structure composed of a 40㎜-thick aluminium honeycomb core and 5㎜-thick woven fabric carbon/epoxy face. In order to evaluate structural behavior and safety of the composite carbody, the static load tests such as vertical load, end compressive load, torsional load and 3-point support load tests have been conducted. These tests were performed under Japanese Industrial Standard (JIS) E 7105 standard. From the tests, maximum deflection was 12.3㎜ and equivalent bending stiffness of the carbody was 0.81×10¹⁴ ㎏fㆍ㎟. Maximum stress of the composite body was lower than 12.2% of strength of the carbon/epoxy. Therefore, the composite body satisfied the Japanese Industrial Standard.