scholarly journals Mass Balancing of Hollow Fan Blades

1986 ◽  
Vol 108 (4) ◽  
pp. 577-582 ◽  
Author(s):  
R. E. Kielb
Keyword(s):  
Mass Balancing ◽  
Section Model ◽  
Fan Blade

This paper uses a typical section model to investigate analytically the effect of mass balancing as applied to hollow, supersonic fan blades. A procedure to determine the best configuration of an internal balancing mass to provide flutter alleviation is developed. This procedure is applied to a typical supersonic shroudless fan blade which is unstable both in the solid configuration and when it is hollow with no balancing mass. The addition of an optimized balancing mass is shown to stabilize the blade at the design condition.

scholarly journals Mass Balancing of Hollow Fan Blades

1986 ◽  
Author(s):  
Robert E. Kielb
Keyword(s):  
Mass Balancing ◽  
Section Model ◽  
Fan Blade

This paper uses a typical section model to analytically investigate the effect of mass balancing as applied to hollow, supersonic fan blades. A procedure to determine the best configuration of an internal balancing mass to provide flutter alleviation is developed. This procedure is applied to a typical supersonic shroudless fan blade which is unstable in both the solid configuration and when it is hollow with no balancing mass. The addition of an optimized balancing mass is shown to stabilize the blade at the design condition.

scholarly journals Use of Dynamic Analysis to Investigate the Behaviour of Short Neutral Sections in the Overhead Line Electrification

2021 ◽  
Vol 6 (5) ◽  
pp. 62
Author(s):  
John Morris ◽  
Mark Robinson ◽  
Roberto Palacin
Keyword(s):  
Dynamic Analysis ◽  
Dynamic Simulation ◽  
Model Simulation ◽  
Analysis Tool ◽  
Overhead Line ◽  
Element Analysis ◽  
Novel Approach ◽  
Section Model ◽  
The Uk ◽  
Neutral Section

The ‘short’ neutral section is a feature of alternating current (AC) railway overhead line electrification that is often unreliable and a source of train delays. However hardly any dynamic analysis of its behaviour has been undertaken. This paper briefly describes the work undertaken investigating the possibility of modelling the behaviour using a novel approach. The potential for thus improving the performance of short neutral sections is evaluated, with particular reference to the UK situation. The analysis fundamentally used dynamic simulation of the pantograph and overhead contact line (OCL) interface, implemented using a proprietary finite element analysis tool. The neutral section model was constructed using physical characteristics and laboratory tests data, and was included in a validated pantograph/OCL simulation model. Simulation output of the neutral section behaviour has been validated satisfactorily against real line test data. Using this method the sensitivity of the neutral section performance in relation to particular parameters of its construction was examined. A limited number of parameter adjustments were studied, seeking potential improvements. One such improvement identified involved the additional inclusion of a lever arm at the trailing end of the neutral section. A novel application of pantograph/OCL dynamic simulation to modelling neutral section behaviour has been shown to be useful in assessing the modification of neutral section parameters.

Failure of induced draft-ID fan blade in coal fired boiler

2021 ◽  
Vol 122 ◽  
pp. 105282
Author(s):  
Chidambaram Subramanian ◽  
Himadri Roy ◽  
Abhijit Mondal ◽  
Debashis Ghosh ◽  
Swarup Kr Laha ◽  
...  
Keyword(s):  
Fan Blade

The Research about the Wind Turbines Pitch Control

2013 ◽  
Vol 773 ◽  
pp. 87-90
Author(s):  
Chen Wang ◽  
De Zhou Meng ◽  
Xu Fang Bo
Keyword(s):  
Wind Power ◽  
Pid Control ◽  
Control Algorithm ◽  
Uneven Distribution ◽  
Pitch Control ◽  
Experimental Platform ◽  
Simulation Results ◽  
Pitch System ◽  
Fan Blade ◽  
Variable Pitch Control

Based on the background of wind power, considering the wind blade sweep area on the uneven distribution, this paper is using the PID control algorithm to control the pitch system. At the same time, this paper is using Siemens SCL to programming, simulating on the experimental platform. Simulation results show the validity of the theory and the feasibility of the system, realizing variable pitch control of fan blade.

Surface Coating Effect on Protection of Icing for Axial Fan Blade

2011 ◽  
Author(s):  
Takeshi Murooka ◽  
Shinichirou Shishido ◽  
Riho Hiramoto ◽  
Takakazu Minoya
Keyword(s):  
Surface Coating ◽  
Axial Fan ◽  
Fan Blade

Dynamic Loading on Turbofan Blades Due to Bird-Strike

2011 ◽  
Vol 133 (12) ◽  
Author(s):  
Sunil K. Sinha ◽  
Kevin E. Turner ◽  
Nitesh Jain
Keyword(s):  
Dynamic Loading ◽  
Time History ◽  
Material Model ◽  
Bird Strike ◽  
Dynamical Equations ◽  
Nonlinear Dynamical ◽  
History Of ◽  
Measured Strain ◽  
Dynamic Loading Condition ◽  
Fan Blade

In the present paper, a hydrodynamic bird material model made up of water and air mixture is developed, which produces good correlation with the measured strain-gauge test data in a panel test. This parametric bird projectile model is used to generate the time-history of the transient dynamic loads on the turbofan engine blades for different size birds impacting at varying span locations of the fan blade. The problem is formulated in 3D vector dynamics equations using a nonlinear trajectory analysis approach. The analytical derivation captures the physics of the slicing process by considering the incoming bird in the shape of a cylindrical impactor as it comes into contact with the rotating fan blades modeled as a pretwisted plate with a camber. The contact-impact dynamic loading on the airfoil produced during the bird-strike is determined by solving the coupled nonlinear dynamical equations governing the movement of the bird-slice in time-domain using a sixth-order Runge-Kutta technique. The analytically predicted family of load time-history curves enables the blade designer to readily identify the critical impact location for peak dynamic loading condition during the bird-ingestion tests mandated for certification by the regulatory agencies.

A Numerical Investigation of Aeroacoustic Fan Blade Flutter

2003 ◽  
Author(s):  
X. Wu ◽  
M. Vahdati ◽  
A. I. Sayma ◽  
M. Imregun
Keyword(s):  
Research Effort ◽  
Pressure Rise ◽  
Acoustic Properties ◽  
Pressure Amplitude ◽  
Ongoing Research ◽  
Blade Flutter ◽  
Fan Blade ◽  
Underlying Mechanisms ◽  
Flutter Margin

This paper reports the results of an ongoing research effort to explain the underlying mechanisms for aeroacoustic fan blade flutter. Using a 3D integrated aeroelasticity method and a single passage blade model that included a representation of the intake duct, the pressure rise vs. mass flow characteristic of a fan assembly was obtained for the 60%–80% speed range. A novel feature was the use of a downstream variable-area nozzle, an approach that allowed the determination of the stall boundary with good accuracy. The flutter stability was predicted for the 2 nodal diameter assembly mode arising from the first blade flap mode. The flutter margin at 64% speed was predicted to drop sharply and the instability was found to be independent of stall effects. On the other hand, the flutter instability at 74% speed was found to be driven by flow separation. Further post-processing of the results at 64% speed indicated significant unsteady pressure amplitude build-up inside the intake at the flutter condition, thus highlighting the link between the acoustic properties of the intake duct and fan blade flutter.

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