scholarly journals Modal Analysis Of Blended Wing-Body UAV

2021 ◽  
Vol 6 (2) ◽  
pp. 68-75
Author(s):  
Neno Ruseno
Keyword(s):  
Modal Analysis ◽  
Leading Edge ◽  
Comsol Multiphysics ◽  
Vibration Characteristic ◽  
The Finite Element Method ◽  
Horizontal Movement ◽  
Aerial Vehicle ◽  
Eigen Frequencies ◽  
Blended Wing Body ◽  
The Difference

The modal analysis deals with the dynamic behavior of mechanical structures under the dynamic vibration. This study aims to analyze the vibration characteristic of the blended wing-body Unmanned Aerial Vehicle (UAV) using modal analysis. The numerical method is used to calculate the eigen frequencies of the system. The COMSOL Multiphysics is selected as the Finite Element Method (FEM) software to simulate the study. The resulted eigen frequencies are 278.05 Hz, 721.28 Hz, 816.39 Hz, 1601.7 Hz, 1699.5 Hz, and 1855.5 Hz. The study also evaluates the displacement of the leading edge of the wing in all axes to understand the modal shapes. The modal shapes found are updrift, swift back, flapping vertical, flapping horizontal, flapping opposite horizontal and flapping more wave in horizontal movement. The comparison of resulted eigen frequencies with a conventional aircraft wing is conducted to understand the difference in its vibration characteristics.

Modal Analysis of the Cable-Stayed Space Truss Combining ANSYS and MSC.ADAMS

2010 ◽  
Vol 121-122 ◽  
pp. 832-837 ◽  
Author(s):  
Jing Jun Zhang ◽  
Ji Tao Zhong ◽  
Li Li He ◽  
Rui Zhen Gao
Keyword(s):  
Qualitative Analysis ◽  
Modal Analysis ◽  
Natural Frequencies ◽  
Vibration Characteristic ◽  
Flexible Bodies ◽  
Space Truss ◽  
Stay Cables ◽  
Dynamic Analyses ◽  
Simulation Results ◽  
The Difference

Modal analysis, which is applied to verify the vibration characteristic of structures, is the basis of various dynamic analyses. In this paper, firstly, a cable-stayed space truss, consisting of stay cables, columns and space truss, is built in ANSYS. Secondly, modal analysis is performed to confirm the natural frequencies of the structure and 10 modes are extracted. Thirdly, a modal neutral file including all necessary information of flexible bodies is generated by ANSYS and then imported into ADAMS for further modal analysis. Finally, comparison of results between ANSYS and ADAMS are summarized and qualitative analysis is carried out aiming at the difference of natural frequencies between ANSYS and ADAMS. The simulation results indicate that the interface between the two tools has strong compatibility regardless of minor errors in it.

Vibration of Press Based on Operational Modal Analysis

2013 ◽  
Vol 312 ◽  
pp. 273-276
Author(s):  
Ming Ming Zhao ◽  
Yi Ming Wang ◽  
Xiang Dong Shi ◽  
Jian Guo Li
Keyword(s):  
Modal Analysis ◽  
Operational Modal Analysis ◽  
Test Method ◽  
Actual Condition ◽  
Vibration Modes ◽  
Vibration Characteristic ◽  
The Finite Element Method ◽  
The Press ◽  
Frequency Identification ◽  
Vibration Modal

Press vibration characteristic is the basic of press fault diagnosis and static optimization. We get press vibration characteristics with Operational Modal Analysis .Comparing theoretical analysis of the finite element method for press with operation modal analysis of test method for press in the actual condition. We get vibration modal orders and vibration modes of press wallboard under natural excitation. The experimental results show that the test modal frequency identification value of Operational Modal Analysis for the press components is highly accurate.

A Study on Damping of Laminated Beams by Modal Analysis

2013 ◽  
Vol 550 ◽  
pp. 33-40
Author(s):  
Djamel Bensahal ◽  
Mohamed Nadir Amrane ◽  
Mounir Kharoubi
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Modal Analysis ◽  
Beam Element ◽  
Structural Damping ◽  
The Finite Element Method ◽  
Cyclic Tests ◽  
Laminated Beams ◽  
The Difference ◽  
Element Method

The paper presents an analysis of the damping of laminated beams with four different stacking sequences. The experimental investigation was conducted using tensile cyclic tests for different laminates studied. The impulse technique was chosen to perform modal analysis of the ease of implementation and quickness of the test. The numerical analysis is performed by the finite element method using beam element. The difference between strain energies for both cases damaged and undamaged are calculated by the finite element method. The structural damping of the different beams is evaluated from these energies. The decrease in frequency for different rates of loading shows the loss of stiffness for all materials studied.

An Investigation of the Distribution of Electric Potential and Space Charge in a Silicon Nanowire

2014 ◽  
Vol 69 (10-11) ◽  
pp. 597-605 ◽  
Author(s):  
A. Wesam Al-Mufti ◽  
Uda Hashim ◽  
Md. Mijanur Rahman ◽  
Tijjani Adam
Keyword(s):  
Finite Element Method ◽  
Space Charge ◽  
Electric Potential ◽  
Silicon Nanowire ◽  
Electrical Potential ◽  
Comsol Multiphysics ◽  
The Finite Element Method ◽  
Simulation Experiments ◽  
Different Dimensions

AbstractThe distribution of electric potential and space charge in a silicon nanowire has been investigated. First, a model of the nanowire is generated taking into consideration the geometry and physics of the nanowire. The physics of the nanowire was modelled by a set of partial differential equations (PDEs) which were solved using the finite element method (FEM). Comprehensive simulation experiments were performed on the model in order to compute the distribution of potential and space charge. We also determined, through simulation, how the characteristic of the nanowire is affected by its dimensions. The characterization of the resulting nanowire, calculated by COMSOL Multiphysics, shows different dimensions and their effect on space charge and electrical potential

scholarly journals Modal analysis of an iced offshore composite wind turbine blade

2021 ◽  
pp. 0309524X2110116
Author(s):  
Oumnia Lagdani ◽  
Mostapha Tarfaoui ◽  
Mourad Nachtane ◽  
Mourad Trihi ◽  
Houda Laaouidi
Keyword(s):  
Wind Turbine ◽  
Modal Analysis ◽  
Turbine Blade ◽  
Natural Frequencies ◽  
Wind Turbine Blade ◽  
Resonance Phenomenon ◽  
Mode Shapes ◽  
The Finite Element Method ◽  
Numerical Work ◽  
Composite Blades

In the far north, low temperatures and atmospheric icing are a major danger for the safe operation of wind turbines. It can cause several problems in fatigue loads, the balance of the rotor and aerodynamics. With the aim of improving the rigidity of the wind turbine blade, composite materials are currently being used. A numerical work aims to evaluate the effect of ice on composite blades and to determine the most adequate material under icing conditions. Different ice thicknesses are considered in the lower part of the blade. In this paper, modal analysis is performed to obtain the natural frequencies and corresponding mode shapes of the structure. This analysis is elaborated using the finite element method (FEM) computer program through ABAQUS software. The results have laid that the natural frequencies of the blade varied according to the material and thickness of ice and that there is no resonance phenomenon.

Study and Simulate the Air Pollution Based on the Finite Difference Method

2012 ◽  
Vol 518-523 ◽  
pp. 2820-2824
Author(s):  
Yi Ni Guo ◽  
Yan Zhang ◽  
Jian Wang ◽  
Ye Huang
Keyword(s):  
Finite Element Method ◽  
Air Pollution ◽  
Finite Difference ◽  
Finite Difference Method ◽  
Difference Method ◽  
The Finite Element Method ◽  
Liquid Diffusion ◽  
Continuous Problems ◽  
The Finite Difference Method ◽  
The Difference

The finite difference method that is the finite element method is used to solve the plane continuous problems. In this article, the theory and method of the finite difference method, as well as the application on the boundary problem are introduced. By analyzing the potential flew field equation and liquid diffusion equation, they are discreted using the difference method and the numerical analysis under certain boundary condition is conducted. In air pollution, the smoke in the diffusion is typical planar continuous problems. In this paper, the finite difference method is used to analyse and simulate the spread of the smoke.

scholarly journals Aerodynamic Analysis of Blended Wing Body - Unmanned Aerial Vehicle (BWB-UAV) Equipped with Horizontal Stabilizers

2019 ◽  
Vol 256 ◽  
pp. 02004
Author(s):  
Nornashiha Mohd Saad ◽  
Wirachman Wisnoe ◽  
Rizal Effendy Mohd Nasir ◽  
Zurriati Mohd Ali ◽  
Ehan Sabah Shukri Askari
Keyword(s):  
Unmanned Aerial Vehicle ◽  
Cfd Simulation ◽  
Lift Coefficient ◽  
Angle Of Attack ◽  
Flight Test ◽  
Longitudinal Direction ◽  
Static Stability ◽  
Pitching Moment ◽  
Aerial Vehicle ◽  
Blended Wing Body

This paper presents an aerodynamic characteristic study in longitudinal direction of UiTM Blended Wing Body-Unmanned Aerial Vehicle Prototype (BWB-UAV Prototype) equipped with horizontal stabilizers. Flight tests have been conducted and as the result, BWB experienced overturning condition at certain angle of attack. Horizontal stabilizer was added at different location and size to overcome the issue during the flight test. Therefore, Computational Fluid Dynamics (CFD) analysis is performed at different configuration of horizontal stabilizer using Spalart - Allmaras as a turbulence model. CFD simulation of the aircraft is conducted at Mach number 0.06 or v = 20 m/s at various angle of attack, α. The data of lift coefficient (CL), drag coefficient (CD), and pitching moment coefficient (CM) is obtained from the simulations. The data is represented in curves against angle of attack to measure the performance of BWB prototype with horizontal stabilizer. From the simulation, configuration with far distance and large horizontal stabilizer gives steeper negative pitching moment slope indicating better static stability of the aircraft.

scholarly journals The Search of Spatial Functions of Pressure in Adjustable Hydrostaticradial Bearing

2015 ◽  
Vol 9 (1) ◽  
pp. 23-26 ◽  
Author(s):  
Dmytro Fedorynenko ◽  
Sergiy Boyko ◽  
Serhii Sapon
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Elastic Deformation ◽  
Tangential Direction ◽  
The Finite Element Method ◽  
Radial Bearing ◽  
Operational Characteristics ◽  
Service Conditions ◽  
The Difference ◽  
Element Method

Abstract The analysis of spatial functions of pressure considering the geometrical deviations and the elastic deformation of conjugate surace have been considered. The analysis of spatial functions of pressure is performed by the finite element method. The difference of the size of pressure in a tangential direction of a pocket of a support under various service conditions has been investigated. A recommendation for improving of operational characteristics in regulated hydrostatic radial bearing has been developed.

Silica Nanocomposite Membrane for Dehumidification

2017 ◽  
Author(s):  
Omar Almahmoud ◽  
Tae-Youl Choi ◽  
Young-Soo Seo ◽  
Hyo-Sun Kim ◽  
Kevin A. Johnson
Keyword(s):  
Water Vapor ◽  
Flow Rate ◽  
Driving Forces ◽  
Comsol Multiphysics ◽  
The Finite Element Method ◽  
Dry Air ◽  
Hydrophobic Polymer ◽  
Silica Nanocomposite ◽  
Novel Design ◽  
Polyurethane Membrane

Various designs of novel membrane (silica nanocomposite polyurethane membrane) were tested for its optimal configuration in a membrane-based dehumidification system. This membrane was designed with a hydrophobic polymer matrix with hydrophilic silica nanochains. In this dehumidification process, two driving forces were suggested: concentration gradient of water vapor in the atmospheric air channel due to sweep gas and pressure gradient due to vacuum. This paper describes validation of the model configurations using the finite element method software (COMSOL Multiphysics) with experiments. Pressurized air enters an air duct at 1–5 liters per minute flow rate. Air is then humidified using a misting nozzle until saturation. Then the humid air passes by the membrane with a vacuum pump connected vertically to the duct to maximize the dehumidification rate. A novel design showed water vapor reduction from 19.4 grams of water vapor per kilogram of dry air to 16.9 grams of water vapor per kilogram of dry air for the 1 liter per minute flow rate of the 47 mm diameter membrane.

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