BACKGROUND While it is generally accepted that inertial impaction will lead to particle loss as aerosol is being carried into the pulmonary airways, most predictive aerosol deposition models adopt the hypothesis that the inhaled particles that remain airborne will distribute according to the gas flow distribution between airways downstream. METHODS Using a 3D printed cast of human airways, we...

-In this paper we present some of the most practical problems of convective heat transport to or from a rigid surface, the flow in the vicinity of the body is in turbulent motion. On the hand, at the solid-fluid interface itself, the noslip boundary condition ensures that turbulent velocity fluctuations vanish. But, at the wall, the diffusive transport of heat and momentum in the fluid is preci...

It has been well-known for over six decades that the addition of minute amounts of long polymer chains to organic solvents, or water, can lead to significant turbulent drag reduction. This discovery has had many practical applications such as in pipeline fluid transport, oil well operations, vehicle design and submersible vehicle projectiles, and more recently arteriosclerosis treatment. Howeve...

In this paper, the effects of two flow-induced vibration (FIV) mitigation components on hard disk drive (HDD) airflow, vortex splitters and flow diverters, were verified. The edges of the components were also modified by filleting and the resulting effect on airflow determined. A perspective review on HDDs and their operation, and the mechanism and mitigation of FIV was discussed. Three suitabl...

This report details the findings and recommendations from the Turbulent Flow Simulation at the Exascale: Opportunities and Challenges Workshop, which was held August, 4–5, 2015, and was sponsored by the U.S. Department of Energy (DOE) Office of Advanced Scientific Computing Research (ASCR). The workshop objectives were to define and describe the challenges and opportunities that computing at th...

The lecture represents significant advances in understanding of the transfer processes mechanism in turbulent separated flows. Based upon experimental data suggesting the governing role of generated local pressure gradient that takes place in the immediate vicinity of the wall in separated flow as a result of intense instantaneous accelerations induced by large-scale vortex flow structures simi...

Particle laden turbulent flows occur in a variety of industrial applications. While the numerical simulation of such flows has seen significant advances in recent years, it still remains a challenging problem. Many studies investigated the rheology of dense suspensions in laminar flows as well as the dynamics of point-particles in turbulence. Here wewill present results on the development of nu...

In this research we have implemented the Random Vortex Method to calculate velocity fields of fluids inside open cavities in both turbulent and laminar flows. the Random Vortex Method is a CFD method (in both turbulent and laminar fields) which needs the Schwarz-Christoffel transformation formula to map the physical geometry into the upper half plane. In some complex geometries like the flow in...

Long-term Research Objective: The scientific objectives of this project are: 1. To describe and characterize the physical mechanisms which determine how most of the noise radiates from a finite fluid-filled pipe with turbulent flow. 2. To determine criteria which estimate the relative importance of these various mechanisms. 3. To develop experimental and analytical techniques for investigating ...