The three-dimensional interaction of a supernova remnant with an interstellar cloud

1992 ◽  
Vol 390 ◽  
pp. L17 ◽  
Author(s):  
James M. Stone ◽  
Michael L. Norman
Keyword(s):  
Supernova Remnant ◽  
Three Dimensional ◽  
Interstellar Cloud ◽  
Dimensional Interaction

Three-Dimensional Interaction Effects in an Internally Multicracked Pressurized Thick-Walled Cylinder— Part I: Radial Crack Arrays

1996 ◽  
Vol 118 (3) ◽  
pp. 357-363 ◽  
Author(s):  
M. Perl ◽  
C. Levy ◽  
J. Pierola
Keyword(s):  
Radial Crack ◽  
Crack Depth ◽  
Three Dimensional ◽  
Internal Surface ◽  
Interaction Effects ◽  
Life Assessment ◽  
Fatigue Life Assessment ◽  
Dimensional Interaction ◽  
Least Squares Fit ◽  
Wide Range

Under certain conditions, numerous internal surface cracks develop in pressurized thick-walled cylinders, both in the radial and longitudinal directions. For fatigue life assessment of such vessels, the 3-D interaction effects among these cracks on the prevailing stress intensity factors (SIFs) need evaluation. In Part I of this paper, radial crack arrays are considered exclusively. The mode I SIF distribution for a wide range of semi-circular and semi-elliptical cracks are evaluated. The 3-D analysis is performed via the finite element method with the submodeling technique, employing singular elements along the crack front. SIFs are evaluated for arrays of up to n = 180 cracks; for a wide range of crack depth to wall thickness ratios, a/t, from 0.05 to 0.6; and, for various ellipticities of the crack, i.e., the ratio of crack depth to semicrack length, a/c, from 0.2 to 2. Using a least-squares fit, two simple expressions for the most critical (n = 2) SIFs are obtained for sparse and dense crack arrays. The formulas, which are functions of a/t and a/c, are of very good engineering accuracy. The results clearly indicate that the SIFs are considerably affected by the interaction among the cracks in the array as well as the three-dimensionality of the problem. In Part II of this paper, the interaction effects between longitudinal coplanar cracks will be analyzed.

scholarly journals Comparative analysis of calculations of strip foundation, taking into account the influence of adjoined building with different soil models

2019 ◽  
Vol 97 ◽  
pp. 04006
Author(s):  
Nataliia Lobacheva ◽  
Vadim Griniov
Keyword(s):  
Three Dimensional ◽  
Natural Occurrence ◽  
Strip Foundation ◽  
Soil Base ◽  
Existing Building ◽  
Dimensional Interaction ◽  
Coulomb Model ◽  
The Difference ◽  
Hardening Soil Model ◽  
Properties Of Soil

The necessity to take into account the properties of soil foundations, which depend not only on the conditions of their natural occurrence, but also on the stress state, led researchers to create a large number of different soil models. This article provides is to clarify the patterns and features of the three-dimensional interaction of strip foundations with the soil base in conditions of dense urban development with the use of various design soil models and comparison with field observations. Three soil models (the Mohr-Coulomb model, the Hardening-Soil model, model of the Klepikov stiffness coefficient) are considered. The calculation stages displayed a true picture of the construction of a new building (dismantling of the floor of an existing building, excavation, etc.). As a result of numerical experiments with a use of Plaxis and methods for calculating structures on a deformable base was received values settlement of strip foundations in applying three soil models. The difference of the calculated values of strip foundation settlement is defined in percentage. The geodesic monitoring confirms the validity of the research.

The Three-Dimensional Interaction of a Shock Wave with a Turbulent Boundary Layer

1966 ◽  
Vol 17 (3) ◽  
pp. 231-252 ◽  
Author(s):  
A. McCabe
Keyword(s):  
Boundary Layer ◽  
Shock Wave ◽  
Turbulent Boundary Layer ◽  
Reasonable Agreement ◽  
Three Dimensional ◽  
Side Wall ◽  
Approximate Theory ◽  
Streamwise Vorticity ◽  
Supersonic Wind Tunnel ◽  
Dimensional Interaction

SummaryExperiments are described on the interaction of the shock wave generated by a wedge in a supersonic wind tunnel with the turbulent boundary layer on the side wall. It is shown that the onset of separation appears to be largely affected by the action of streamwise vorticity in the interaction region. A simple approximate theory based on this concept shows reasonable agreement with the experimental results. Comparisons have been made with two-dimensional interactions of normal shocks and boundary layers, but they did not produce any conclusive results.

scholarly journals The three-dimensional interaction of a vortex pair with a wall

1997 ◽  
Vol 9 (10) ◽  
pp. 2967-2980 ◽  
Author(s):  
J. Alan Luton ◽  
Saad A. Ragab
Keyword(s):  
Three Dimensional ◽  
Vortex Pair ◽  
Dimensional Interaction

INFLOW/OUTFLOW CONDITIONS FOR TIME-HARMONIC INTERNAL FLOWS

2002 ◽  
Vol 10 (02) ◽  
pp. 155-182 ◽  
Author(s):  
OLIVER V. ATASSI ◽  
AMR A. ALI
Keyword(s):  
Acoustic Waves ◽  
Numerical Scheme ◽  
Truncation Error ◽  
Numerical Solutions ◽  
Three Dimensional ◽  
Internal Flows ◽  
Vortex Sheets ◽  
Dimensional Interaction ◽  
Time Harmonic ◽  
Annular Cascade

Inflow/Outflow conditions are formulated for time-harmonic waves in a duct governed by the Euler equations. These conditions are used to compute the propagation of acoustic and vortical disturbances and the scattering of vortical waves into acoustic waves by an annular cascade. The outflow condition is expressed in terms of the pressure, thus avoiding the velocity discontinuity across any vortex sheets. The numerical solutions are compared with the analytical solutions for acoustic and vortical wave propagation with and without the presence of vortex sheets. Grid resolution studies are also carried out to discern the truncation error of the numerical scheme from the error associated with numerical reflections at the boundary. It is observed that even with the use of exponentially accurate boundary conditions, the dispersive characteristics of the numerical scheme may result in small reflections from the boundary that slow convergence. Finally, the three-dimensional interaction of a wake with a flat plate cascade is computed and the aerodynamic and aeroacoustic results are compared with those of lifting surface methods.

scholarly journals Mapping the three-dimensional dust extinction towards the supernova remnant S147 – the S147 dust cloud

2017 ◽  
Vol 472 (4) ◽  
pp. 3924-3935 ◽  
Author(s):  
B.-Q. Chen ◽  
X.-W. Liu ◽  
J.-J. Ren ◽  
H.-B. Yuan ◽  
Y. Huang ◽  
...  
Keyword(s):  
Supernova Remnant ◽  
Dust Cloud ◽  
Three Dimensional ◽  
Dust Extinction

Viscous Flow in an Annulus With a Sector Cavity

1982 ◽  
Vol 104 (4) ◽  
pp. 500-504 ◽  
Author(s):  
V. O’Brien
Keyword(s):  
Biharmonic Equation ◽  
Three Dimensional ◽  
Axial Flow ◽  
Cavity Flow ◽  
Three Dimensional Flow ◽  
Circular Annulus ◽  
Dimensional Interaction ◽  
Laminar Mixing ◽  
Flow Through ◽  
Finite Difference Solution

The two-dimensional interaction of a circular shear flow and a sector cavity flow is predicted by finite-difference solution of the governing biharmonic equation for steady Stokes planar flow. The location of the dividing streamline is a function of geometry, lying perhaps wholly within the cavity or bulging up into the circular annulus. Also pressure-driven axial flow through the annular configuration is predicted by numerical solution of the governing Poisson equation. The results can be combined with the planar solution to describe a steady three-dimensional flow field which will enhance laminar mixing.

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