Improved design model for thin-walled cold-formed purlins continuously connected to sandwich panel roofing

2010 ◽  
pp. 153-154 ◽  
Author(s):  
M Georgescu ◽  
V Ungureanu
Keyword(s):  
Sandwich Panel ◽  
Design Model ◽  
Thin Walled ◽  
Improved Design

Design criteria for insulation materials applied in timber frame assemblies

2018 ◽  
Vol 9 (3) ◽  
pp. 252-263 ◽  
Author(s):  
Mattia Tiso ◽  
Alar Just
Keyword(s):  
Cross Sections ◽  
Fire Resistance ◽  
Design Methodology ◽  
Research Study ◽  
Design Model ◽  
Insulation Material ◽  
Content Type ◽  
Insulation Materials ◽  
Timber Frame ◽  
Improved Design

Purpose Insulation materials’ contribution to the fire resistance of timber frame assemblies may vary considerably. At present, Eurocode 5 provides a model for fire design of the load-bearing function of timber frame assemblies with cavities completely filled with stone wool. Very little is known about the fire protection provided by other insulation materials. An improved design model which has the potential to consider the contribution of any insulation material has been introduced by the authors. This paper aims to analyze the parameters that describe in a universal way the protection against the charring given by different insulations not included in Eurocode 5. Design/methodology/approach A series of model-scale furnace tests of floor specimens for three different insulation materials were carried out. An analysis on the charring depth of the residual cross-sections was conducted by means of a resistograph device. Findings The study explains the criteria and procedure followed to derive the coefficients for the improved design model for three insulations involved in the study. Originality/value This research study involves a large experimental work which forms the basis of the proposed design model. This study presents an important step for fire resistance calculations of timber frame assemblies.

Improved Design of Thin-Walled Square Tube for Energy Absorption

2012 ◽  
Vol 460 ◽  
pp. 389-392
Author(s):  
Jian Wang ◽  
Hong Tu Sun ◽  
Jing Huang
Keyword(s):  
Energy Absorption ◽  
Stable Structure ◽  
Peak Acceleration ◽  
Collision Process ◽  
Thin Walled ◽  
Improved Design ◽  
Front Impact ◽  
Initial Peak ◽  
Extensional Collapse

Thin-walled tubes are the main structures to absorb the energy in front impact at the desired controlled collision. A thin-walled square tube is designed by use of a double deck square tube with clapboards which has a stable structure with less Euler deformation in front impact. More deformations of extensional collapse in the double deck square tube with clapboards improve the performance of structures for energy absorption. Induced slots are employed in the square tube to decrease the peak acceleration in front impact. Collision process can be controlled by the slots for the stable deformation and reduced initial peak acceleration

A New Design Method for Axially Loaded Thin-Walled Cylindrical Shells Based on Elasto-Plastic Buckling Analysis

2019 ◽  
Author(s):  
Peng Jiao ◽  
Zhiping Chen ◽  
He Ma
Keyword(s):  
Design Method ◽  
Cylindrical Shells ◽  
Load Carrying Capacity ◽  
Test Results ◽  
Geometric Imperfections ◽  
Compression Load ◽  
Load Carrying ◽  
Weight Design ◽  
Thin Walled ◽  
Improved Design

Abstract In engineering, thin-walled cylindrical shells subjected to axial compression load are very sensitive to geometric imperfections and are prone to buckling. However, how to reasonably take into account the influence of geometric imperfections on the load carrying capacity of thin-walled cylindrical shells is always the bottleneck of light-weight design of these structures. In this paper, four perturbation load approach (4PLA) is adopted to consider the influence of geometric imperfections. By judging the potential buckling status of cylindrical shells, a new improved design method based on 4PLA for thin-walled cylindrical shells is proposed, in which the influence of radius-to-thickness ratio, length-to-radius ratio, Young’s modulus and material yield strength are systematically considered. Correspondingly, the buckling tests for two steel cylindrical shells with the same geometric and material parameters are conducted. Compared with the experimental results and other test results in open literatures, the superiority and safety of proposed method for the preliminary design of thin-walled cylindrical shells are validated.

scholarly journals Verification of a design model and evaluation of a technique of manufacturing aircraft engine composite parts on the basis of dynamic tests

2020 ◽  
Vol 18 (4) ◽  
pp. 52-63
Author(s):  
A. V. Zinin ◽  
A. N. Arkhipov ◽  
D. P. Kholobtsev ◽  
Yu. A. Ravikovich ◽  
A. O. Shevjakov ◽  
...  
Keyword(s):  
Experimental Evaluation ◽  
Complex Geometry ◽  
Aircraft Engine ◽  
Design Model ◽  
Natural Oscillations ◽  
Local Characteristics ◽  
Damped Oscillations ◽  
Thin Walled ◽  
Effective Design

The results of finite element modeling and experimental evaluation of dynamic characteristics (vibration modes and frequencies) of the composite element of aircraft power plant structures are presented. The aim of the work is to develop effective design and technological schemes for thin-walled complex-geometry composite parts, taking into account the peculiarities of mechanical behavior of polymer composite materials to the fullest extent possible. A method for determining the parameters of natural oscillations of composite parts in a free state using a ping test is developed, which allows excluding the influence of kinematic boundary conditions and obtaining frequency characteristics that depend only on the local characteristics of the material which are primarily determined by the manufacturing technology. According to the results of measurements of the amplitude-frequency parameters of the dynamic response, spectrograms of damped oscillations are obtained the peak values of which correspond to the experimental evaluation of the natural frequencies of the composite part. Verification of the design model was carried out according to the results of the ping test and a method for assessing the quality of technological processes of manufacturing thin-walled carbon fiber structures was proposed.

scholarly journals Development of Design Methodology for a Small Solar-Powered Unmanned Aerial Vehicle

2018 ◽  
Vol 2018 ◽  
pp. 1-10 ◽  
Author(s):  
Parvathy Rajendran ◽  
Howard Smith
Keyword(s):  
Trend Analysis ◽  
Electric Propulsion ◽  
Design Feature ◽  
Design Model ◽  
Design Models ◽  
Validation Experiment ◽  
Aerial Vehicle ◽  
Solar Powered ◽  
Improved Design ◽  
Mathematical Design

Existing mathematical design models for small solar-powered electric unmanned aerial vehicles (UAVs) only focus on mass, performance, and aerodynamic analyses. Presently, UAV designs have low endurance. The current study aims to improve the shortcomings of existing UAV design models. Three new design aspects (i.e., electric propulsion, sensitivity, and trend analysis), three improved design properties (i.e., mass, aerodynamics, and mission profile), and a design feature (i.e., solar irradiance) are incorporated to enhance the existing small solar UAV design model. A design validation experiment established that the use of the proposed mathematical design model may at least improve power consumption-to-take-off mass ratio by 25% than that of previously designed UAVs. UAVs powered by solar (solar and battery) and nonsolar (battery-only) energy were also compared, showing that nonsolar UAVs can generally carry more payloads at a particular time and place than solar UAVs with sufficient endurance requirement. The investigation also identified that the payload results in the highest effect on the maximum take-off weight, followed by the battery, structure, and propulsion weight with the three new design aspects (i.e., electric propulsion, sensitivity, and trend analysis) for sizing consideration to optimize UAV designs.

Strength design model for thin-walled structures

2016 ◽  
Vol 59 (1) ◽  
pp. 126-133
Author(s):  
Z. J. Wang ◽  
L. H. Kang ◽  
A. S. Kretov ◽  
S. Huang
Keyword(s):  
Design Model ◽  
Thin Walled Structures ◽  
Strength Design ◽  
Thin Walled
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