Abstract The dose-response model has been widely used for quantifying the risk of infection airborne diseases like COVID-19. in room-average analysis and using passive scalars as a proxy aerosol transport. However, it not employed estimation numerical simulations droplet dispersion. In this work, we develop framework evaluation probability dispersion model. We introduce version that can incorporate higher transmissibility variant strains SARS-CoV2 effect vaccination evaluating infection....

Negative Magnus lift acting on a sphere rotating about the axis perpendicular to an incoming flow was investigated using large-eddy simulation at three Reynolds numbers of 1.0 × 104, 2.0 105, and 1.14 106. The numerical methods used were first validated non-rotating sphere, spatial resolution around determined so as reproduce laminar separation, reattachment, turbulent transition boundary layer observed in vicinity critical number. exhibited positive or negative effect depending number...

The aero-train is an innovative, high-efficiency, and low-consumption vehicle that uses the wing-in-ground effect. It utilizes orbital high voltage to obtain a lift-to-drag ratio while generates significant noise, which dominated by trailing-edge noise from multi-directional wing. Study of generation propagation great significance in realizing active passive reduction noise; however, various types mechanisms under near-wall conditions are unknown. In this study, wings with different relative...

Writing high-performance solvers for engineering applications is a delicate task. These codes are often developed on an application to basis, highly optimized solve certain problem. Here, we present our work developing general simulation framework efficient computation of time-resolved approximations complex industrial flow problems—Complex Unified Building cube method (CUBE). To address the challenges emerging, modern supercomputers, suitable data structures and communication patterns...

Unsteady aerodynamic forces acting on vehicles during a dynamic steering action were investigated by numerical simulation, with special focus the vehicles' yaw and lateral motions. Two sedan-type slightly different geometries at front pillar, side skirt, under cover, around wheel adopted for comparison. In first report, surface pressure body total behind measured in an on-road experiment. Then relationships between motion unsteady characteristics cornering motions discussed. this second...

Summary We propose a full Eulerian incompressible solid‐fluid interaction scheme capable of achieving high parallel efficiency and easily generating meshes for complex solid geometries. While good scalability formulation has been reported by Sugiyama et al, their analysis was carried out using uniform Cartesian mesh an artificial compressibility method. Typically, it is more challenging to achieve hierarchical fully formulation. In addition, the conventional methods require large...

Transmission of infectious respiratory diseases through airborne dispersion viruses poses a great risk to public health. In several major diseases, one the main modes transmission is droplets. Virus laden droplets and aerosols can be generated during coughing, sneezing speaking. These remain suspended in air transported by airflow posing infection individuals who might come contact with them. With this background, work, we present numerical framework for simulation sputum using implicit...

In this study, the flow field around face masks was visualized and evaluated using computational fluid dynamics. The protective efficiency of suppressing droplet infection owing to differences in shape, medium, doubling usage is predicted. Under ongoing COVID-19 pandemic condition, many studies have been conducted highlight that airborne transmission main route. However, virus prevention effect has not sufficiently discussed, thus remains as a controversial issue. Therefore, we aimed provide...

Large-eddy simulations are conducted for a rotating golf ball and smooth sphere at constant rotational speed the subcritical, critical supercritical Reynolds numbers. A negative lift force is generated in regime both models, whereas positive forces subcritical regimes. Detailed analysis on flow separations different sides of models reveals mechanism Magnus effect. Further investigation unsteady aerodynamics effect motion development lateral wake structures. It found that helps to stabilize...

As evidenced by the worldwide pandemic, respiratory infectious diseases and their airborne transmission must be studied to safeguard public health. This study focuses on emission transport of speech-generated droplets, which can pose risk infection depending loudness speech, its duration initial angle exhalation. We have numerically investigated these droplets into human tract way a natural breathing cycle in order predict probability three strains SARS-CoV-2 person who is listening at...

• The object of the study is wing trailing edge noise an innovative groundeffect vehicle, aero-train. This a novel approach in reduction by applying serrated designs under high-speed and near-wall conditions. uses compressible LES/Möhring method for numerical simulation, considering reflection diffraction from wall semi-free space. analysis acoustic results this based on details transient boundary layer flow detail. proposes passive bionic strategy using (TE) to be applied aero-train's...