Catalogue Search | MBRL
Are you sure you want to remove the book from the shelf?
{{itemTitle}}
82,840
result(s) for
"Rapids"
Sort by:
Equatorially trapped nonlinear water waves in a $\\unicodeSTIX{x1D6FD}$ -plane approximation with centripetal forces
In this paper we present an exact and explicit nonlinear solution of a
$\\unicode[STIX]{x1D6FD}$
-plane approximation to the governing equations which retains all Coriolis terms. The solution represents an equatorially trapped wave propagating in the presence of a constant underlying background current. In particular, we show that retention of the (relatively) small-scale centripetal forces in the governing equations enables us to admit currents of any physically plausible magnitude in the background flow.
Journal Article
Caught in the rapids
\"During a trip to survey a river, Dr. Bea and Joe are suddenly swept into the water! In this exciting title, the pair must use their science knowledge to survive the rushing rapids and dangerous challenges waiting around each bend.\"-- Provided by publisher.
Book
Making the MexiRican City
Large numbers of Latino migrants began to arrive in Grand Rapids,
Michigan, in the 1950s. They joined a small but established
Spanish-speaking community of people from Texas, Mexico, and Puerto
Rico. Delia Fernández-Jones merges storytelling with historical
analysis to recapture the placemaking practices that these
Mexicans, Tejanos, and Puerto Ricans used to create a new home for
themselves. Faced with entrenched white racism and hostility,
Latinos of different backgrounds formed powerful relationships to
better secure material needs like houses and jobs and to recreate
community cultural practices. Their pan-Latino solidarity crossed
ethnic and racial boundaries and shaped activist efforts that
emphasized working within the system to advocate for social change.
In time, this interethnic Latino alliance exploited cracks in both
overt and structural racism and attracted white and Black partners
to fight for equality in social welfare programs, policing, and
education.
Groundbreaking and revelatory, Making the MexiRican
City details how disparate Latino communities came together to
respond to social, racial, and economic challenges.
eBook
One fatal mistake
\"Her son accidentally killed a man. They cover it up. Then, everything goes wrong. When eighteen-year-old Joshua Mayo takes a man's life in a horrible accident, he leaves the scene and the body without reporting the crime to the police. He hopes to put the awful night behind him, and move on with his life. But, of course, he ends up telling his mother Karen what happened. Karen has raised Joshua on her own in Cedar Rapids, Iowa--and she thought they'd finally made it. He was doing well in school and was only months from starting college. After hearing his dark confession, she's forced to make a choice no parent should have to make, one that draws them both into a web of deceit that will change their lives forever--if they make it out alive..\"-- Provided by publisher.
Book
Turbulent Couette flow up to ${{Re}}_\\tau =2000
Two simulations of turbulent Couette flows were performed at friction Reynolds numbers of 1000 and 2000 in a large box of dimensions $L_x=16{\\rm \\pi} h$, $L_y=2h$ and $L_z=6{\\rm \\pi} h$, where h is the semi-height of the channel. The study focuses on the differences in the intensity and scaling of turbulence at these two Reynolds numbers. The 2000 case showed a lack of a clear log layer with a higher value of the Von Kármán constant $\\kappa$ than Poiseuille channels. The intensities were well-scaled in the buffer layer and below, with a second maximum of the streamwise intensity at approximately 350 wall units. Contrary to Poiseuille channels, the dissipation scales close to the wall in wall units. This fact can be attributed to the constant value of the derivative of the streamwise intensity in wall units. The intensities of the 2000 case showed remarkable differences compared with those at Reynolds number 1000 at the channel centre, likely due to the organization of large scales of the streamwise fluctuactions, $u$. These large scales were thought to be considered ‘infinite’. However, for the 2000 case, while all the structures have a width of $\\ell _z \\approx 6/8{\\rm \\pi} h$, their length varies from $\\ell _x \\approx 6{\\rm \\pi} h$ to $\\ell _x \\approx 16{\\rm \\pi} h$, which clearly contradicts the trends obtained in the past. This is a new effect that has not been reported for turbulent Couette flow and points to the uncertainty and sensitivity that is observed for certain statistical quantities.
Journal Article
No barriers : a blind man's journey to kayak the Grand Canyon
\"'No Barriers is about my journey since coming down from Mt. Everest in 2001, and the path to where I am today. It is the story of my own life, the personal and professional struggles in the pursuit of growth, learning, and family, as well as a dream to kayak one of the world's great rivers as a blind athlete. It is also about the many people I've encountered along the way who possess what I call a 'No Barriers' mindset, who live a No Barriers life'\"-- Provided by publisher.
Book
Turbulent pipe flow downstream of a $90{{}^\\circ} $ bend
Time-resolved stereoscopic PIV was used to investigate the curvature-induced structures downstream of a
$90{{}^\\circ} $
bend at Reynolds numbers between
$20\\times 1{0}^{3} $
and
$115\\times 1{0}^{3} $
. Data were taken at three downstream locations to investigate the evolution of the structures. Snapshot proper orthogonal decomposition (POD) analysis shows that the most energetic structure is not the well-known Dean motion but a bimodal single cell structure with alternating direction of rotation, called the ‘swirl switching’ mode. The strengths of the Dean motion and the swirl-switching structures are similar, indicating that the difference in energy is related to their duration of occurrence, where the Dean motion is associated with a comparatively rapid transition between the two states in the swirl switching mode.
Journal Article
Vortex separation cascades in simulations of the planar flow past an impulsively started cylinder up to $\\boldsymbol{Re=100}\\ \\boldsymbol{000}
Direct numerical simulations of the flow past an impulsively started cylinder at high Reynolds numbers (25k–100k) reveal an intriguing portrait of unsteady separation. Vorticity generation and vortex shedding entails a cascade of separation events on the cylinder surface that are reminiscent of Kelvin–Helmholtz instabilities. Primary vortices roll up along the cylinder surface as a result of instabilities of the initially attached vortex sheets, followed by vortex eruptions, creation of secondary vorticity and formation of dipole structures that are subsequently ejected from the surface of the cylinder. We analyse the vortical structures and their relationship to the forces experienced by the cylinder. This striking cascade of vortex instabilities may serve as reference for reduced-order models of flow separation and as guide for flow control of separated flows at high Reynolds numbers.
Journal Article
Nu\\sim Ra^{1/2}$ scaling enabled by multiscale wall roughness in Rayleigh–Bénard turbulence
In turbulent Rayleigh–Bénard (RB) convection with regular, mono-scale, surface roughness, the scaling exponent
$\\unicode[STIX]{x1D6FD}$
in the relationship between the Nusselt number
$Nu$
and the Rayleigh number
$Ra$
,
$Nu\\sim Ra^{\\unicode[STIX]{x1D6FD}}$
can be
${\\approx}1/2$
locally, provided that
$Ra$
is large enough to ensure that the thermal boundary layer thickness
$\\unicode[STIX]{x1D706}_{\\unicode[STIX]{x1D703}}$
is comparable to the roughness height. However, at even larger
$Ra$
,
$\\unicode[STIX]{x1D706}_{\\unicode[STIX]{x1D703}}$
becomes thin enough to follow the irregular surface and
$\\unicode[STIX]{x1D6FD}$
saturates back to the value for smooth walls (Zhu et al., Phys. Rev. Lett., vol. 119, 2017, 154501). In this paper, we prevent this saturation by employing multiscale roughness. We perform direct numerical simulations of two-dimensional RB convection using an immersed boundary method to capture the rough plates. We find that, for rough boundaries that contain three distinct length scales, a scaling exponent of
$\\unicode[STIX]{x1D6FD}=0.49\\pm 0.02$
can be sustained for at least three decades of
$Ra$
. The physical reason is that the threshold
$Ra$
at which the scaling exponent
$\\unicode[STIX]{x1D6FD}$
saturates back to the smooth wall value is pushed to larger
$Ra$
, when the smaller roughness elements fully protrude through the thermal boundary layer. The multiscale roughness employed here may better resemble the irregular surfaces that are encountered in geophysical flows and in some industrial applications.
Journal Article