Topic
Oblique shock
About: Oblique shock is a research topic. Over the lifetime, 6551 publications have been published within this topic receiving 119823 citations.
Papers published on a yearly basis
Papers
More filters
177 citations
TL;DR: In this article, the authors present basic and well-established results on the physics of SWBLI corresponding to a description in terms of an average two-dimensional steady flow, and some emphasis is placed on unsteadiness, which constitutes a salient feature of this phenomenon.
Abstract: When the flow past a vehicle flying at high velocity becomes supersonic, shock waves form, caused either by a change in the slope of a surface, a downstream obstacle or a back pressure constraining the flow to become subsonic In modern aerodynamics, one can cite a large number of circumstances where shock waves are present The encounter of a shock wave with a boundary layer results in complex phenomena because of the rapid retardation of the boundary layer flow and the propagation of the shock in a multilayered structure The consequence of shock wave/boundary layer interaction (SWBLI) are multiple and often critical for the vehicle or machine performance The shock submits the boundary layer to an adverse pressure gradient which may strongly distort its velocity profile At the same time, in turbulent flows, turbulence production is enhanced which amplifies the viscous dissipation leading to aggravated performance losses In addition, shock-induced separation most often results in large unsteadiness which can damage the vehicle structure or, at least, severely limit its performance The article first presents basic and well-established results on the physics of SWBLI corresponding to a description in terms of an average two-dimensional steady flow Such a description allows apprehending the essential properties of SWBLIs and drawing the main features of the overall flow structure associated with SWBLI Then, some emphasis is placed on unsteadiness in SWBLI which constitutes a salient feature of this phenomenon In spite of their importance, fluctuations in SWBLI have been considered since a relatively recent date although they represent a domain which deserves a special attention because of its importance for a clear physical understanding of interactions and of its practical consequences as in aeroelasticity
175 citations
TL;DR: In this article, the acceleration of particles at planar, infinitessimally thin shocks, as well as to plasma simulations in which low-energy ions are injected and accelerated at quasi-perpendicular shocks with internal structure is considered.
Abstract: The present evaluation of the basic techniques and illustrative results of charged particle-modeling numerical codes suitable for particle acceleration at oblique, fast-mode collisionless shocks emphasizes the treatment of ions as test particles, calculating particle dynamics through numerical integration along exact phase-space orbits. Attention is given to the acceleration of particles at planar, infinitessimally thin shocks, as well as to plasma simulations in which low-energy ions are injected and accelerated at quasi-perpendicular shocks with internal structure.
175 citations
TL;DR: In this paper, the authors performed sub-parsec scale simulations of two idealized molecular clouds with different masses undergoing a collision and investigated the effect of turbulence and collision speed on the resulting core population and compared the cumulative mass distribution to cores in observed GMCs.
Abstract: We performed sub-parsec (~0.06 pc) scale simulations of two idealized molecular clouds with different masses undergoing a collision. Gas clumps with densities greater than 10–20 g cm–3 (0.3 × 104 cm–3) were identified as pre-stellar cores and tracked throughout the simulation. The colliding system showed a partial gas arc morphology with core formation in the oblique shock front at the collision interface. These characteristics support NANTEN observations of objects suspected to be colliding giant molecular clouds (GMCs). We investigated the effect of turbulence and collision speed on the resulting core population and compared the cumulative mass distribution to cores in observed GMCs. Our results suggest that a faster relative velocity increases the number of cores formed but that cores grow via accretion predominately while in the shock front, leading to a slower shock being more important for core growth. The core masses obey a power-law relation with index γ = –1.6, in good agreement with observations. This suggests that core production through collisions should follow a similar mass distribution as quiescent formation, albeit at a higher mass range. If cores can be supported against collapse during their growth, then the estimated ram pressure from gas infall is of the right order to counter the radiation pressure and form a star of 100 M ☉.
169 citations
TL;DR: This work uses multimillion-atom molecular dynamics simulations to study shock wave propagation in fcc crystals and finds even more interesting behavior of shocks propagating in other low-index directions.
Abstract: We use multimillion-atom molecular dynamics simulations to study shock wave propagation in fcc crystals As shown recently, shock waves along the direction form intersecting stacking faults by slippage along {l_brace}111{r_brace} close-packed planes at sufficiently high shock strengths We find even more interesting behavior of shocks propagating in other low-index directions: for the case, an elastic precursor separates the shock front from the slipped (plastic) region Shock waves along the direction generate a leading solitary wave train, followed (at sufficiently high shock speeds) by an elastic precursor, and then a region of complex plastic deformation (c) 2000 The American Physical Society
168 citations