11,479 research outputs found
Lifting surface theory for a helicopter rotor in forward flight
A lifting surface theory was developed for a helicopter rotor in forward flight for compressible and incompressible flow. The method utilizes the concept of the linearized acceleration potential and makes use of the vortex lattice procedure. Calculations demonstrating the application of the method are given in terms of the lift distribution on a single rotor, a two-bladed rotor, and a rotor with swept-forward and swept-back tips. In addition, the lift on a rotor which is vibrating in a pitching mode at 4/rev is given. Compressibility effects and interference effects for a two-bladed rotor are discussed
Lifting surface theory for a helicopter rotor in forward flight
A lifting surface theory has been developed for a helicopter rotor in forward flight for incompressible flow. The method utilized the concept of the linearized acceleration potential and make use of the vortex lattice procedures. Results in terms of lift coefficient slope for several forward flight conditions are given
A study of longitudinal oscillations of propellant tanks and wave propagations in feed lines. Part I - One-dimensional wave propagation in a feed line
Longitudinal oscillations of propellant tanks and wave propagations in feed lines with streaming flui
A study of longitudianl oscillations of propellant tanks and wave propagations in feed lines. Part IV - Longitudinal oscillation of a propellant-filled flexible hemispherical tank
Longitudinal oscillation of propellant-filled flexible hemispherical tan
A study of longitudinal oscillations of propellant tanks and wave propagations in feed lines. Part V - Longitudinal oscillation of a propellant-filled flexible oblate spheroidal tank
Analytical method for determining axisymmetric longitudinal mode shapes and frequencies of incompressible and inviscid fluid in pressurized flexible oblate spheroidal propellant tan
Transport equation for 2D electron liquid under microwave radiation plus magnetic field and the Zero Resistance State
A general transport equation for the center of mass motion is constructed to
study transports of electronic system under uniform magnetic field and
microwave radiation. The equation is applied to study 2D electron system in the
limit of weak disorder where negative resistance instability is observed when
the radiation field is strong enough. A solution of the transport equation with
spontaneous AC current is proposed to explain the experimentally observed
Radiation-Induced Zero Resistance State.Comment: 9 pages, 1 figur
A Study of Longitudinal Oscillations of Propellant Tanks and Wave Propagations in Feed Lines. Part III - Wave Propagation in an Elastic Pipe Filled with Incompressible Viscous Streaming Fluid
Longitudinal wave propagation in elastic pipe filled with incompressible viscous streaming flui
A study of longitudinal oscillations of propellant tanks and wave propagations in feed lines. Part 1 - Propagating pressure waves in a fluid-filled cylindrical shell
Theory and equations for propagating pressure waves in liquid filled cylindrical shell
Half-Skyrmions and Spike-Vortex Solutions of Two-Component Nonlinear Schrodinger Systems
Recently, skyrmions with integer topological charges have been observed
numerically but have not yet been shown rigorously on two-component systems of
nonlinear Schrodinger equations (NLSE) describing a binary mixture of
Bose-Einstein condensates. Besides, half-skyrmions characterized by
half-integer topological charges can also be found in the nonlinear sigma model
which is a model of the Bose-Einstein condensate of the Schwinger bosons. Here
we prove rigorously the existence of half-skyrmions which may come from a new
type of soliton solutions called spike-vortex solutions of two-component
systems of NLSE on the entire plane. These spike-vortex solutions having spikes
in one component and a vortex in the other component may form half-skyrmions.
By Liapunov-Schmidt reduction process, we may find spike-vortex solutions of
two-component systems of NLSE.Comment: to appear in J.Math.Phy
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