We present high-fidelity numerical simulations of expiratory biosol transport during normal breathing under indoor, stagnant air conditions with and without a facile mask. investigate mask efficacy to suppress the spread saliva particles that is underpinnings existing social distancing recommendations. The incorporate effect human anatomy consider spectrum particulate sizes range from 0.1 10 μm while also accounting for their evaporation. elucidate vorticity dynamics show mask, particulates...

The reproduction number is broadly considered as a key indicator for the spreading of COVID-19 pandemic. Its estimated value measure necessity and, eventually, effectiveness interventions imposed in various countries. Here we present an online tool data-driven inference and quantification uncertainties number, well time points 51 European study relied on Bayesian calibration SIR model with data from reported daily infections these fitted data, most countries, without individual tuning...

We present a high performance computing framework for large scale simulation of compressible multicomponent flows, applied to cloud cavitation collapse. The governing equations are discretized by Godunov-type finite volume method on uniform structured grid. bubble interface is captured diffuse and treated as mixing region the liquid gas phases. based our Cubism library which enables efficient treatment high-order compact stencil schemes that can harness capabilities massively parallel...

We investigate the process of cloud cavitation collapse through large-scale simulation a composed 12500 gas bubbles. A finite volume scheme is used on structured Cartesian grid to solve Euler equations, and bubbles are discretized by diffuse interface method. propagation wave front provide comparisons simplified models. analyze flow field identify each bubble its associated microjet. find that oscillation frequency velocity magnitude microjets depend local strength hence radial position in...

We present a solver for three-dimensional compressible multicomponent flow based on the Euler equations. The is finite volume scheme structured grids and advances solution using an explicit Runge-Kutta time stepper. numerical requires computation of flux divergence approximate Riemann problem. quantity most expensive task in algorithm. Our implementation takes advantage compute capabilities heterogeneous CPU/GPU architectures. computational problem organized subdomains small enough to be...

We quantify uncertainties in the location and magnitude of extreme pressure spots revealed from large scale multi-phase flow simulations cloud cavitation collapse. examine clouds containing 500 cavities related to their initial spatial arrangement. The resulting 2000-dimensional space is sampled using a non-intrusive computationally efficient Multi-Level Monte Carlo (MLMC) methodology. introduce novel optimal control variate coefficients enhance variance reduction MLMC. proposed fidelity...

The reproduction number (R0) is broadly considered as a key indicator for the spreading of COVID-19 pandemic. estimation its value with respect to threshold 1.0 measure need, and eventually effectiveness, interventions imposed in various countries. Here we present an online tool data driven inference quantification uncertainties R0 well time points 51 European study relies on Bayesian calibration simple established SIR model from reported daily infections. able fit most countries without...

We quantify uncertainties in the location and magnitude of extreme pressure spots revealed from large scale multiphase flow simulations cloud cavitation collapse. examine clouds containing 500 cavities related to their initial spatial arrangement. The resulting 2,000-dimensional space is sampled using a nonintrusive computationally efficient multilevel Monte Carlo (MLMC) methodology. introduce novel empirically optimal control variate coefficients enhance variance reduction MLMC. proposed...

We present the high performance implementation of a new algorithm for simulating multiphase flows with bubbles and drops that do not coalesce. The is more efficient than standard multi-marker volume-of-fluid method since number required fields does depend on bubbles. capabilities our methods are demonstrated simulations foaming waterfall where we analyze effects coalescence prevention bubble size distribution show how rising cluster up as foam water surface. Our open-source enables...

We present CubismAMR, a C++ library for distributed simulations with block-structured grids and Adaptive Mesh Refinement. A numerical method to solve the incompressible Navier-Stokes equations is proposed, that comes novel approach of solving pressure Poisson equation on an adaptively refined grid. Validation verification results are presented, flow past impulsively started cylinder.

Large scale simulations of complex systems ranging from climate and astrophysics to crowd dynamics, produce routinely petabytes data are projected reach the zettabytes level in coming decade. These enable unprecedented insights but at same their effectiveness is hindered by enormous sizes associated with computational elements respective output quantities interest that impose severe constraints on storage I/O time. In this work, we address these challenges through a novel software framework...

We present a high performance computing framework for multiphase, turbulent flows on structured grids. The computational methods are validated number of benchmark problems such as the Taylor-Green vortex that extended by inclusion bubbles in flow field. examine effect kinetic energy dissipation rate and provide extensive data bubble trajectories velocities may assist development engineering models. implementation solver massively parallel, GPU enhanced architectures allows large scale...

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