scholarly journals Flutter of Fan Blades in the Aircraft Engine in the Three-Dimensional Subsonic Gas Flow

2021 ◽  
pp. 13-21
Author(s):  
Vitaly Gnesin ◽  
Lyubov Kolodyazhnaya ◽  
Yuriy Bykov ◽  
Igor Kravchenko ◽  
Oleksii Petrov ◽  
...  
Keyword(s):  
Gas Flow ◽  
Operation Mode ◽  
Three Dimensional ◽  
Aircraft Engine ◽  
Three Dimensional Model ◽  
Blade Vibration ◽  
Blade Ring ◽  
Subsonic Gas Flow ◽  
The Given ◽  
Operational Development

Aeroelasticity problems arise in the different fields of technology. The accident-free operation of the airborne machines is one of the most important factors that should be taken into account during their designing and upgrading. The solution of this problem involves the implementation of many measures to provide the system reliability on the whole, including its individual elements, in particular aircraft engine, its fan whose wide-chord blades can be exposed to the wreckage due to different reasons including the aeroelastic effects, i.e. self-excited vibrations. As a result, the origination of the aeroelastic phenomenon (flutter) in design and off-design modes should be eliminated at the stage of the design and operational development of the rotor wheel that would result in a considerable increase of the level of reliability of the aircraft engine. Based on the analysis of the available methods used for the flutter prediction we can draw a conclusion that the most promising approach to the analysis of the aeroelastic behavior of the blade ring of fan is the use of the method based on the three-dimensional model of the aerodynamics and dynamics (the method used for the solution of the coupled aeroelastic problem). By solving the coupled aeroelastic problem of the nonstationary aerodynamics and elastic vibrations of the blades we can get the amplitude –frequency blade vibration spectrum for the three-dimensional gas flow, including forced vibrations and self-excided vibrations in order to increase the reliability of the blade row of turbine machines. The developed numerical method was used for the analysis of the aeroelastic behavior of the blade ring of the fan mounted in the airborne engine for the operation mode of 3520 rmp with appropriate boundary conditions at the inlet and outlet behind the ring. The computation data confirmed the origination of self-vibrations for the given fan operation mode.

Three-Dimensional Arc Modeling inside Non-Transferred Plasma Torch

2012 ◽  
Vol 217-219 ◽  
pp. 1407-1410
Author(s):  
Hai Ling Han ◽  
Qing Lin Wang
Keyword(s):  
Flow Rate ◽  
Plasma Torch ◽  
Gas Flow ◽  
Numerical Models ◽  
Three Dimensional ◽  
Arc Length ◽  
Gas Flow Rate ◽  
Three Dimensional Model ◽  
Anode Spot ◽  
The Given

Numerical models have been developed to study the characteristics of an arc inside the non-transferred plasma torch. A few of them have considered the diameter of anode spot and arc length in given current and gas flow rate. In this work, a three-dimensional model is developed to simulate power and entropy in the given current and diameter of anode spot. Different combinations of diameter of anode spot and arc length can produce torch power that corresponds to given current and gas flow rate. From the possible combinations of the diameter of anode spot and arc length predicted for given current and gas flow rate, the most feasible combination is obtained.

Quantitative Analysis of Gas Flow in a Planar SOFC

2012 ◽  
Vol 472-475 ◽  
pp. 2084-2087 ◽  
Author(s):  
Kai Wang ◽  
Yi Sheng Zhang ◽  
Jian Li
Keyword(s):  
Quantitative Analysis ◽  
Gas Flow ◽  
Three Dimensional ◽  
Analysis Method ◽  
Three Dimensional Model ◽  
Velocity Change ◽  
Gas Channel ◽  
Negative Effect ◽  
Quantitative Analysis Method ◽  
Cfd Method

Computational Fluid Dynamics (CFD) method was adopted to establish the three dimensional model for cathode gas channel of planar SOFC and simulate the gas flow in the channel of a single cell. A quantitative analysis method was presented to research the status of gas flow. The characteristics and diagram of velocity change were obtained by using the quantitative analysis method. Furthermore, it was found that gas leak has a negative effect on the uniformity of gas flow, which is more obvious in the region near the leak side.

Anatomically based three-dimensional model of airways to simulate flow and particle transport using computational fluid dynamics

2005 ◽  
Vol 98 (3) ◽  
pp. 970-980 ◽  
Author(s):  
Caroline van Ertbruggen ◽  
Charles Hirsch ◽  
Manuel Paiva
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Particle Deposition ◽  
Gas Flow ◽  
Three Dimensional ◽  
Bronchial Tree ◽  
Inspiratory Flow ◽  
Three Dimensional Model ◽  
Viscous Pressure ◽  
Curved Ducts

We have studied gas flow and particle deposition in a realistic three-dimensional (3D) model of the bronchial tree, extending from the trachea to the segmental bronchi (7th airway generation for the most distal ones) using computational fluid dynamics. The model is based on the morphometrical data of Horsfield et al. (Horsfield K, Dart G, Olson DE, Filley GF, and Cumming G. J Appl Physiol 31: 207–217, 1971) and on bronchoscopic and computerized tomography images, which give the spatial 3D orientation of the curved ducts. It incorporates realistic angles of successive branching planes. Steady inspiratory flow varying between 50 and 500 cm3/s was simulated, as well as deposition of spherical aerosol particles (1–7 μm diameter, 1 g/cm3 density). Flow simulations indicated nonfully developed flows in the branches due to their relative short lengths. Velocity flow profiles in the segmental bronchi, taken one diameter downstream of the bifurcation, were distorted compared with the flow in a simple curved tube, and wide patterns of secondary flow fields were observed. Both were due to the asymmetrical 3D configuration of the bifurcating network. Viscous pressure drop in the model was compared with results obtained by Pedley et al. (Pedley TJ, Schroter RC, and Sudlow MF. Respir Physiol 9: 387–405, 1970), which are shown to be a good first approximation. Particle deposition increased with particle size and was minimal for ∼200 cm3/s inspiratory flow, but it was highly heterogeneous for branches of the same generation.

Numerical Study of the Pusher-Type Billet Reheating Furnace

2005 ◽  
Author(s):  
Linjiang Zou ◽  
Chaoxiang Li ◽  
Yinmei Yuan ◽  
Wei Guo ◽  
Fan Yang ◽  
...  
Keyword(s):  
Software Package ◽  
High Speed ◽  
Gas Flow ◽  
Numerical Study ◽  
Three Dimensional ◽  
Cfd Model ◽  
Dimensional Model ◽  
Three Dimensional Model ◽  
Iron And Steel ◽  
Reheating Furnace

In the present work, a commercial CFD software package, FLUENT, was used to develop a three-dimensional model of pusher-type billet reheating furnace for the second high speed wire rod plant of XiangTan Iron and steel Co. Ltd. The purpose of the study was to gain a better understanding of the gas flow and velocity and pressure distribution in the furnace. The results show that the numerical results are in agreement with the practice and the characteristics of the furnace configuration. The CFD model can be used to improve the performance and structure by analyzing and studying the behavior of the reheating furnace.

scholarly journals 3-D simulation using for hydraulic calculation of the heat Accumulator

2018 ◽  
Vol 240 ◽  
pp. 05011
Author(s):  
Olha Kletska ◽  
Anatoliy Falendysh ◽  
Arthur Kagramanjan ◽  
Andrey Onishchenko
Keyword(s):  
3D Modeling ◽  
Pressure Difference ◽  
Static Pressure ◽  
Three Dimensional ◽  
Hydraulic Calculation ◽  
Dimensional Model ◽  
Three Dimensional Model ◽  
Software Environment ◽  
Heat Accumulator ◽  
The Given

The article is devoted to the peculiarities of hydraulic calculation of the heat accumulator in the software environment for 3D modeling - SolidWorks. Based on the results of the calculation, the values of the distribution of the velocities of the water flow and the distribution of the static pressure in the given plane of the heat accumulator were obtained, which eventually made it possible to identify the problem areas in the three-dimensional model and obtain the values of the pressure difference.

The Simulation and Optimization on Flow Field in Intake Port of Engine Based on RE and CFD

2014 ◽  
Vol 1079-1080 ◽  
pp. 926-929
Author(s):  
Dan Han ◽  
Qian Wang ◽  
Bing Huan Li ◽  
Guo Jun Zhang ◽  
Shuo Wang
Keyword(s):  
Flow Field ◽  
Laser Scanning ◽  
Gas Flow ◽  
Gasoline Engine ◽  
Three Dimensional ◽  
Flow Characteristics ◽  
Turbulence Models ◽  
Intake Port ◽  
Three Dimensional Model ◽  
Simulation And Optimization

Intake port is an important part of the gasoline engine, its structure will influence the gas flow characteristics which directly affects the performance of the engine [1]. In this paper, three-dimensional CFD calculation and structural optimization were used to research the performance of gasoline engine. Firstly, the method of laser scanning and UG software were used to reverse modeling engine exhaust port and get the three-dimensional model. Secondly, after setting boundary conditions and turbulence models, the air flowing through the intake ports were simulated by FLUENT software respectively. Finally, based on numerical methods, the pressure field, velocity field were shown. The results of the simulation of flow field characteristics analysis show that the simulation and experimental results are in good agreement.

A Three-Dimensional Model for Piston Ring-Pack Dynamics and Blow-By Gas Flow

2004 ◽  
Author(s):  
Liang Liu ◽  
Tian Tian
Keyword(s):  
Dynamic Behavior ◽  
Gas Flow ◽  
Piston Ring ◽  
Three Dimensional ◽  
Beam Theory ◽  
Ring Structure ◽  
Three Dimensional Model ◽  
Secondary Motion ◽  
Piston Ring Pack ◽  
Ring Pack

A three-dimensional (3D) model for piston ring-pack dynamics and blow-by gas flow was developed to enable more in-depth analyses of the ring-pack performance. This model predicts the 3D dynamic behavior of compression rings and twin-land oil control ring due to the ring’s non-axisymmetric properties, bore distortion and piston secondary motion. Finite element beam theory is used for ring structure calculation. Gas flows along the axial and circumferential directions of the power cylinder system are resolved simultaneously with the ring dynamics. The model was applied to a heavy-duty diesel engine. Particular emphasis was placed on the dynamics of keystone type of top ring, and the stability of the second ring with a twist chamfer and twin-land oil control ring under the influence of piston secondary motion. The variations of the gas pressure and ring dynamic behavior along the circumference are discussed.

scholarly journals Blackbox Optimization for Aircraft Engine Blades With Contact Interfaces

2019 ◽  
Vol 141 (6) ◽  
Author(s):  
Julien Lainé ◽  
Elsa Piollet ◽  
Florence Nyssen ◽  
Alain Batailly
Keyword(s):  
Three Dimensional ◽  
Optimization Procedure ◽  
Aircraft Engine ◽  
Design Stage ◽  
Contact Interactions ◽  
Direct Optimization ◽  
Blade Vibration ◽  
Blade Shape ◽  
Geometry Parameterization ◽  
Vibration Simulation

In modern aircraft engines, reduced operating clearances between rotating blade tips and the surrounding casing increase the risk of blade/casing structural contacts, which may lead to high blade vibration levels. Therefore, structural contacts must now be accounted for as early as in the engine design stage. As the vibrations resulting from contact are intrinsically nonlinear, direct optimization of blade shapes based on vibration simulation is not realistic in an industrial context. A recent study on a blade featuring significantly lower vibration levels following contact event identified a potential criterion to estimate a blade sensitivity to contact interactions. This criterion is based on the notion of dynamic clearance, a quantity describing the evolution of the blade/casing clearance as the blade vibrates along one of its free-vibration modes. This paper presents an optimization procedure, which minimizes the dynamic clearance as a first step toward the integration of structural criteria in blade design. A dedicated blade geometry parameterization is introduced to allow for an efficient optimization of the blade shape. The optimization procedure is applied to the three-dimensional (3D) properties of two different blades. In both cases, initial and optimized blades are compared by means of an in-house numerical tool dedicated to the simulation of structural contact events with a surrounding casing. The simulations focus on rubbing phenomena, involving the vibration of a single blade. Simulation results show a significant reduction of vibration levels following contact interactions for the optimized blades. Critical speeds related to the mode on which the dynamic clearance is computed are successfully eliminated by the blade shape optimization. For the investigated blade geometries, backward sweep and backward lean angles are associated with reduced contact interactions compared to forward sweep and forward lean angles.

New semi three-dimensional approach for simulation of Lamb wave clamp-on ultrasonic gas flowmeter

Sensor Review ◽  
2020 ◽  
Vol 40 (4) ◽  
pp. 465-476
Author(s):  
Seyed Foad Mousavi ◽  
Seyed Hassan Hashemabadi ◽  
Jalil Jamali
Keyword(s):  
Lamb Wave ◽  
Gas Flow ◽  
Computing Time ◽  
Three Dimensional ◽  
Dimensional Approach ◽  
Three Dimensional Model ◽  
Contact Mode ◽  
New Approach ◽  
Content Type ◽  
2D Simulation

Purpose The purpose of this study is to numerically simulate the Lamb wave propagation through a clamp-on ultrasonic gas flowmeter (UGF) in contact mode, using a new semi three-dimensional approach. Moreover, experimental and analytical modeling results for transit time difference method have been used to confirm the simulation results at different gas flow velocities from 0.3 to 2.4 m/s. Design/methodology/approach The new semi three-dimensional approach involves the simulation of the flow field of the gas in a three-dimensional model and subsequently the simulation of wave generation, propagation and reception in a two-dimensional (2D) model. Moreover, the analytical model assumes that the wave transitions occur in a 2D mode. Findings The new approach is a semi three-dimensional approach used in this work, has better accuracy than a complete 2D simulation while maintaining the computing time and costs approximately constant. It is faster and less expensive than a complete 3D simulation and more accurate than a complete 2D simulation. It was concluded that the new approach could be extended to simulate all types of ultrasonic gas and non-gas flowmeters, even under harsh conditions. Originality/value In this work, a new approach for the numerical simulation of all types of ultrasonic flowmeters is introduced. It was used for simulation of a Lamb wave ultrasonic flow meter in contact mode.

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