PH
Ping He
14 records found
1
We use a database of direct numerical simulations to evaluate parametrizations for energy dissipation rate in stably stratified flows. We show that shear-based formulations are more appropriate for stable boundary layers than commonly used buoyancy-based formulations. As part of
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In this study, we explore several integral and outer length scales of turbulence which can be formulated by using the dissipation of temperature fluctuations (χ) and other relevant variables. Our analyses directly lead to simple yet non-trivial parameterizations for both spatiall
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Kolmogorov's 1941 hypothesis on local isotropy is only applicable for scales smaller than the outer length scales (OLS). By utilizing data from direct numerical simulations and wind tunnel experiments, we quantify OLS in stratified flows.@en
The influence of space-charge layers on the ionic charge transport over cathode-solid electrolyte interfaces in all-solid-state batteries remains unclear because of the difficulty to unravel it from other contributions to the ion transport over the interfaces. Here, we reveal the
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In Wyngaard et al., 1971, a simple model was proposed to estimate Cn 2 in the atmospheric surface layer, which only requires routine meteorological information (wind speed and temperature) as input from two heights. This Cn 2 model is k
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Development of similarity relationships for energy dissipation rate and temperature structure parameter in stably stratified flows
A direct numerical simulation approach
In this study, a newly developed direct numerical simulation (DNS) solver is utilized for the simulations of numerous stably stratified open-channel flows with bulk Reynolds number (Reb) spanning 3400–16,900. Overall, the simulated bulk Richardson number (Rib
Optical wave propagation through the atmosphere is complicated by organized atmospheric structures, spanning a wide range of length and time scales, which induce spatio-temporal variability in refraction. Therefore, when considering long-range optical ray trajectories, the influe
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Spatial variations of refractivity significantly dictate the characteristics of optical wave propagation through the atmosphere. Consequently, the ability to simulate such propagation is highly dependent upon the accurate characterization of refractivity along the propagation pat
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In this paper, we reconstruct the meteorological and optical environment during the time of Titanic's disaster utilizing a state-of-the-art meteorological model, a ray-tracing code, and a unique public-domain dataset called the Twentieth Century Global Reanalysis. With high fidel
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Conventional techniques used to model optical wave propagation through the Earth's atmosphere typically as-sume flow fields based on various empirical relationships. Unfortunately, these synthetic refractive index fields do not take into account the influence of transient macrosc
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In this study, we present a brief review on the existing approaches for optical turbulence estimation in various layers of the Earth's atmosphere. The advantages and disadvantages of these approaches are also discussed. An alternative approach, based on mesoscale modeling with pa
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In this paper, we propose a novel parameterization for optical turbulence (C2n) simulations in the atmosphere. In this approach, C2n is calculated from the output of atmospheric models using a high-order turbulence closure scheme. An important feature of thi
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Estimating refractive index structure parameter (C2n) profiles in the atmosphere
A wavelet transform-based approach
We propose a novel framework for the estimation of C2n in the atmosphere by utilizing an inherent vertical scaling characteristics of the temperature fields. Observations from a field campaign over the Hawaii island are used for rigorous validation. Furthermore, the strength of t
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We report the continuing development of an extensive simulated database of stably stratified turbulence which includes episodic bursting events. Utilizing this database, a few physically-based parameterizations for the structure parameters are being formulated.@en