Electromagnetic eigenfrequency of anisotropic inhomogeneous axisymmetric toroidal plasmas of arbitrary meridional cross section

1986 ◽  
Vol 40 (1) ◽  
pp. 99-103 ◽  
Author(s):  
Ferdinand F. Cap
Keyword(s):  
Cross Section ◽  
Toroidal Plasmas ◽  
Meridional Cross Section

Inertial waves in a rotating spherical shell

1997 ◽  
Vol 341 ◽  
pp. 77-99 ◽  
Author(s):  
M. RIEUTORD ◽  
L. VALDETTARO
Keyword(s):  
Spherical Shell ◽  
Cross Section ◽  
Shear Layers ◽  
Inertial Waves ◽  
Ekman Number ◽  
Distribution Of Eigenvalues ◽  
Simple Rules ◽  
Meridional Cross Section ◽  
Zero Viscosity ◽  
The Web

The structure and spectrum of inertial waves of an incompressible viscous fluid inside a spherical shell are investigated numerically. These modes appear to be strongly featured by a web of rays which reflect on the boundaries. Kinetic energy and dissipation are indeed concentrated on thin conical sheets, the meridional cross-section of which forms the web of rays. The thickness of the rays is in general independent of the Ekman number E but a few cases show a scaling with E1/4 and statistical properties of eigenvalues indicate that high-wavenumber modes have rays of width O(E1/3). Such scalings are typical of Stewartson shear layers. It is also shown that the web of rays depends on the Ekman number and shows bifurcations as this number is decreased.This behaviour also implies that eigenvalues do not evolve smoothly with viscosity. We infer that only the statistical distribution of eigenvalues may follow some simple rules in the asymptotic limit of zero viscosity.

The Calculation of the Quasi-Three-Dimensional Flow in an Axial Gas Turbine

1975 ◽  
Vol 97 (2) ◽  
pp. 283-294 ◽  
Author(s):  
S. Biniaris
Keyword(s):  
Numerical Solution ◽  
Cross Section ◽  
Three Dimensional ◽  
Entire Region ◽  
Three Dimensional Flow ◽  
Total Enthalpy ◽  
Blade Thickness ◽  
Meridional Cross Section ◽  
The Finite Difference Method ◽  
The Stability

The flow is calculated within the entire region from far upstream to far downstream of the blade rows and this not only between the blade rows but especially within the blade passages. It is assumed that the flow is steady, adiabatic, and inviscid. However, compressibility, blade forces in all directions, blade thickness, and total enthalpy gradients are taken into account. The shape of the meridional cross section can be arbitrary. The blades can be either cylindrical or twisted. The numerical solution is based on the finite-difference method. The discretization error, the stability error, and the iteration error of the numerical solution are determined.

The Influence on the Meridional Impeller Shape on the Energy-Transfer in Centrifugal Compressors

1980 ◽  
Author(s):  
K. Bammert ◽  
M. Rautenberg ◽  
P. Knapp
Keyword(s):  
Cross Section ◽  
Static Pressure ◽  
Radial Flow ◽  
Suction Side ◽  
Wake Flow ◽  
Blade Shape ◽  
Meridional Cross Section ◽  
Compressor Performance ◽  
Different Shapes ◽  
Wake Zone

Three radial flow impellers were tested having an elliptic blade shape and identical blade geometry at inlet and exit but different shapes of the meridional contours. The compressor maps with pressure ratios up to 2.9:1 are compared using time-dependent measurements of the static pressure at the shroud and of the flow angles closely downstream of the impeller. From these measurements, the influence of impeller shap on the jet-and-wake flow is discussed. It is shown that with increasing impeller length, the wake zone at the suction side of the blades can be only partially influenced and friction losses become dominant with respect to compressor performance. A smooth curvature of the meridional cross section of the impeller channel leads to a better jet-wake ratio at impeller exit. Accordingly, the performance characteristic shows higher values especially when the mass flow is increased.

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