Laser Doppler anemometer (LDA) experiments were performed to gain quantitative information on the differences between the large-scale flow phenomena in a non-stenosed and a stenosed model of the carotid artery bifurcation. The influence of the presence of the stenosis was compared to the effect of flow pulse variation to evaluate the feasibility of early detection of stenosis in clinical practi...

This chapter is devoted to investigations of linear stability of plane-parallel flows of an inviscid nonheat-conducting vibrationally excited gas. Some classical results of the theory of linear stability of ideal gas flows, such as the first and second Rayleigh’s theorems and Howard’s theorem, are generalized. An equation of the energy balance of disturbances is derived, which shows that vibrat...

We investigate the stability of a Helmholtz velocity profile in a stably stratified fluid when a lower boundary is present. In addition to the traditional Kelvin-Helmholtz interfacial instability we find an infinitude of unstable internal gravity waves, the most unstable of which bear a close resemblance to disturbances observed in connection with clear air turbulence. It is shown that the grav...

.........................................................................................................................................................................1 Roadside Drainage Design for Channel Stability ..........................................................................................................2 Allowable Velocity and Shear Stress.......................................

We study theoretically the onset of shear banding in the three most common time-dependent rheological protocols: step stress, finite strain ramp (a limit of which gives a step strain), and shear startup. By means of a linear stability analysis we provide a fluid-universal criterion for the onset of banding for each protocol, which depends only on the shape of the experimentally measured time-de...

We describe a steady-state patient with sickle cell anemia (SS disease) who developed sporadic hemoglobinuria, historically related to vigorous exercise. We studied him and four other patients with SS disease and demonstrated exercise-induced hemoglobinemia. To see if SS erythrocytes were abnormally fragile when exposed to shear forces that could be generated in small vessels of exercising musc...

This study compares the effects of fluid shear on the kinetics, adhesion efficiency, stability, and molecular requirements of polymorphonuclear leukocyte (PMN) binding to two colon adenocarcinoma cell-lines, the CD54-negative/sLe(x)-bearing LS174T cells and the CD54-expressing/sLe(x)-low HCT-8 cells. The efficiency of PMN-colon carcinoma heteroaggregation decreases with increasing shear, with P...

Wall shear stress in postcapillary venules varies widely within and between tissues and in response to inflammation and exercise. However, the speed at which leukocytes roll in vivo has been shown to be almost constant within a wide range of wall shear stress, i.e., force on the cell. Similarly, rolling velocities on purified selectins and their ligands in vitro tend to plateau. This may be imp...

The impact of cold temperatures on the shear strength of Scots pine (Pinus sylvestris) joints glued with seven commercially available adhesives was studied in this work. The cold temperatures investigated were: 20, −20, −30, −40, and −50 °C. Generally, within the temperature test range, the shear strength of Scots pine solid wood and wood joints were more resistant to the effect of temperature ...

Problem statement: The presence of vegetation increases the soil burden stability along slopes and reduces soil erosion. Its contribution is due to mechanical (reinforcing soil shear resistance) and hydrologic controls on streambank and superficial landslides. This study presented the results carried out from experimental in situ test focused to study the increased shear resistance of soil bloc...