Search Constraints

Start Over
Filtering by: Creator Smyth, W. D. Remove constraint Creator: Smyth, W. D. Rights Statement In Copyright Remove constraint Rights Statement: In Copyright

Search Results

  • Turbulence in sheared, salt-fingering favorable environment

    Creator:
    Kimura, Satoshi
    Abstract:
    Instability and turbulence in sheared, salt-fingering favorable stratification are studied using three-dimensional direct numerical simulations (DNS). Salt-fingering favorable stratification is gravitationally stable, because the unstable vertical gradient of salinity is stabilized by temperature (warm, salty over cool, fresh water-masses). Salt-fingering instability can occur at the interface of these different water-masses....
    Resource Type:
    Dissertation
    Full Text:
    : Turbulence in Sheared, Salt-fingering Favorable Environment Abstract approved: William D. Smyth

  • Turbulence and biophysical fluxes in the near surface ocean

    Creator:
    Hoecker-Martínez, Martín
    Abstract:
    Vertical transports of plankton, momentum, heat, and turbulence are modeled. A novel integration of high resolution turbulence and biophysical modeling is used to show the influence of a Kelvin-Helmholtz instability on the vertical migration of simple gyrotactic organisms. A viscous limit on mixing driven by shear turbulence is proposed. Large...
    Resource Type:
    Dissertation
    Full Text:
    biophysical fluxes in the near surface ocean. Abstract Approved: William D. Smyth Vertical transports of

  • Destabilization of a Stratified Shear Layer by Ambient Turbulence

    Creator:
    Li, Lin
    Abstract:
    A small eddy viscosity or mass diffusivity that varies with height has been found to have unexpected effects on the Kelvin-Helmholtz (KH) instability of a stably stratified shear layer near the neutral stability boundary. In particular, varying viscosity can increase the growth rate of the instability in contrast to the...
    Resource Type:
    Masters Thesis
    Full Text:
    turbulence in thermohaline staircases. Deep-Sea Res. 34, 689–1696. KIMURA, S., SMYTH, W. D. & KUNZE, E

  • Shear and convective turbulence in a model of thermohaline intrusions

    Creator:
    Mueller, Rachael
    Abstract:
    Thermohaline interleaving is an important mechanism for laterally fluxing salt, heat, and nutrients between oceanic water masses. Interleaving is driven by a release of potential energy resulting from the vastly differing diffusivities of heat and salt in seawater. The flows are composed of stacked intrusions that flux more buoyant and...
    Resource Type:
    Masters Thesis
    Full Text:
    Turbulence in a Model of Thermohaline Intrusions Abstract approved: William D. Smyth Thermohaline

  • Secondary Kelvin-Helmholtz instability in weakly stratified shear flow

    Creator:
    Smyth, William D.
    Abstract:
    The growth of secondary vortices on the braids separating Kelvin–Helmholtz billows is investigated via numerical simulations. The similarity theory of Corcos & Sherman (1976) is extended to include mixing processes with Prandtl number greater than unity, and is shown to provide a useful description of the physics of the braid...
    Resource Type:
    Article
    Full Text:
    billows. 68 W. D. Smyth With very few exceptions (Staquet 1991; Winters, MacKinnon & Mills 2003

  • Linear theory of roll instabilities in the ocean surface layer

    Creator:
    Duncombe, Jenessa R.
    Abstract:
    This thesis describes the results of a linear stability analysis conducted on a simulated wind-forced ocean front. The ocean surface boundary layer regulates exchanges between the ocean and atmosphere, and the presence of turbulence in the surface layer can greatly impact climate and ocean life. Past research has shown that...
    Resource Type:
    Masters Thesis
    Full Text:
    (11) Kv0 d2T dz2 +Kv0K 2T −G0U − dΘ dz W − i(kU + lV )T = −iσT (12) where K 2

  • Characterization of the transition to the progamic phase in Zea mays pollen

    Creator:
    Smyth, Johanna C.
    Abstract:
    The transition of mature pollen to the progamic phase represents an important step in the regulation of plant sexual reproduction. The progamic phase encompasses the initiation of pollen tube germination, growth of the pollen tube through the stigma (the silk in maize) and concludes with fertilization of the female gametophyte....
    Resource Type:
    Dissertation
    Full Text:
    Johanna C. Smyth for the degree of Doctor of Philosophy in Botany and Plant Pathology presented on

  • Instability and Diapycnal Momentum Transport in a Double-Diffusive, Stratified Shear Layer

    Creator:
    Smyth, William D. and Kimura, Satoshi
    Abstract:
    The linear stability of a double-diffusively stratified, inflectional shear flow is investigated. Double-diffusive stratification has little effect on shear instability except when the density ratio R[subscript]ρ is close to unity. Double-diffusive instabilities have significant growth rates and can represent the fastest-growing mode even in the presence of inflectionally unstable shear...
    Resource Type:
    Article
    Full Text:
    -Diffusive, Stratified Shear Layer WILLIAM D. SMYTH AND SATOSHI KIMURA College of Oceanic and Atmospheric

  • Turbulence and Mixing in Holmboe Waves

    Creator:
    Smyth, W. D. and Winters, K. B.
    Abstract:
    Motivated by the tendency of high-Prandtl-number fluids to form sharp density interfaces, the authors investigate the evolution of Holmboe waves in a stratified shear flow through direct numerical simulation. Like their better-known cousins, Kelvin–Helmholtz waves, Holmboe waves lead the flow to a turbulent state in which rapid irreversible mixing takes...
    Resource Type:
    Article
    Full Text:
    Waves W. D. SMYTH College of Oceanic and Atmospheric Sciences, Oregon State University, Corvallis

  • Baroclinic Interleaving Instability: A Second-Moment Closure Approach

    Creator:
    Smyth, W. D., Burchard, H., and Umlauf, L.
    Abstract:
    Interleaving motions on a wide, baroclinic front are modeled using a second-moment closure to represent unresolved fluxes by turbulence and salt fingering. A linear perturbation analysis reveals two broad classes of unstable modes. First are scale-selective modes comparable with interleaving as observed in oceanic fronts. These correspond well with observations...
    Resource Type:
    Article
    Full Text:
    -Moment Closure Approach W. D. SMYTH, H. BURCHARD, AND L. UMLAUF Leibniz Institute for Baltic Sea