In recent years, hollow fan blades have been widely used to meet the requirements of aeroengines for lightweight and better performance. However, blade will change from manufacture shape operating with large deformations during operation. This deviation, if neglected, lead deceptive results structural aerodynamic analysis. existing methods low prediction accuracy or require a lot calculation in...

We give a simple argument proving the lonely runner conjecture in the case where the speed of the runners forms a certain lacunary sequence. This improves an earlier result by Pandey, and is then used to derive that for each number of runners the lonely runner conjecture is true for a set of nonzero measure in a natural probability space.

in the present paper, the aeroelastic stability of helicopter rotor blade is determined using aeroelastic frequency response function. the aeroelastic model of blade is obtained by combining dowell - hodges beam model with loewy unsteady aerodynamic theory which considers an unsteady wake beneath the rotor. equations are formed and aeroelastic frequency response functions are obtained by invert...

Most icing studies use 2D or quasi-3D models, ignoring the effects of blade span and tip icing. In this paper, a new model for predicting 3D vertical axis wind turbine blades by supplementing is established, characteristics under multiple working conditions are simulated step from time scale, unsteady laws compared analyzed. Ice properties surface temperature distribution determine correspondin...

tip leakage loss introduces major part of losses of the rotor in axial gas turbines. therefore, the rotor blade tip has a considerable effect on rotor efficiency. to understand the flow physics of the rotor tip leakage, we solve the flow field for different tip platforms (passive flow control) and by considering coolant tip injection (active flow control). various blade tip configurations such ...

1. Abstract Gas turbine engines for aerospace applications have evolved dramatically over the last 50 years through the constant pursuit for better specific fuel consumption, higher thrust-to-weight ratio, lower noise and emissions all while maintaining reliability and affordability. This paper addresses one facet of this inter-disciplinary optimization problem – optimal design of a turbine bla...

Development of new technologies and combined with creativity and innovation, plays the fundamental role in developing of any community′s value. Thus, in this research the design and production of hydroforming device was introduced. One of the best and most efficient technologies in the world of metal forming is wind turbine blade producing with hydroforming method which seems as an innovative m...

PURPOSE To compare blade cultures in surgery for closed fracture using a single or double blade technique to determine whether the current practice of double blade technique is justified. METHODS 155 men and 29 women aged 20 to 60 (mean, 35) years who underwent surgery for closed fracture with healthy skin at the incision site were included. Patients were block randomised to the single (n=92)...