Periodic motion of three stirrers in a two-dimensional flow can lead to chaotic transport of the surrounding fluid. For certain stirrer motions, the generation of chaos is guaranteed solely by the topology of that motion and continuity of the fluid. Work in this area has focused largely on using physical rods as stirrers, but the theory also applies when the “stirrers” are passive fluid particl...

The problem of free convection flow and heat transfer of a fluid inside a square cavity having adiabatic obstacle positioned in the center of the cavity has been investigated numerically using a penalty finite element method. Calculations have been made for Rayleigh numbers ranging from 10 to 10 for an obstacle of aspect ratios AR=0, 0.4, 0.5, 0.6. Nusselt number results are presented for Prand...

An experimental platform was designed and built for testing the thermal performance of a water/steam cavity receiver. The experimental platform was utilized to investigate the start-up performance and operation characteristics of the receiver. The electrical heating mode was chosen to simulate the non-uniform distribution of heat flux on the surface of absorber tubes inside the cavity. During s...

UNLABELLED This study is performed as a part of research that examines the emission and diffusion characteristics of volatile organic compounds (VOCs) from indoor building materials. In this paper, the flow field and the emission field of VOCs from the surface of building materials in a Field and Laboratory Emission Cell (FLEC) cavity are examined by 3D Computational Fluid Dynamics (CFD) analys...

The response of a supersonic cavity to open-loop forcing with a pulsed-blowing actuator is explored experimentally. It is shown that excitation at frequencies near the Rossiter modes are amplified, while frequencies between the first two Rossiter modes are attenuated. The results clearly demonstrate that the Rossiter modes in the supersonic cavity are weakly damped (not self-excited) modes. The...

The augment of heat transfer and fluid of buoyancy-driven flow of Fe3O4-Water nanofluid in a square cavity under the influence of an external magnetic field is studied numerically. Cold temperature is applied on the side (vertical) walls and high temperature is imposed on the bottom wall while the top wall is kept at thermally insulated. The governing non-dimensional differential equations are ...

In this study the direct-simulation Monte Carlo (DSMC) method is utilized to investigate thermal characteristics of micro- or nanocavity flow. The rarefied cavity flow shows unconventional behaviors which cannot be predicted by the Fourier law, the constitutive relation for the continuum heat transfer. Our analysis in this study confirms some recent observations and shows that the gaseous flow ...

For high-speed air breathing engines, fuel injection and subsequent mixing with air is paramount for combustion. The high freestream velocity poses a great challenge to efficient mixing both in macroscale and microscale. Utilising cavities downstream of fuel injection locations, as a means to hold the flow and stabilise the combustion, is one mechanism which has attracted much attention, requir...

Simulations of supersonic turbulent flow over an open rectangular cavity are performed to observe the effects of length to depth ratio (L/D) of the cavity on the flow structure. Two-dimensional compressible time-dependent Reynolds-averaged Navier-Stokes equations with k-ω turbulence model are solved. A reduced order modeling approach, Proper Orthogonal Decomposition (POD) method, is used to fur...

This paper investigates the interaction between the shear layer over a circular cavity and the flowexcited acoustic response of the volume to shear layer instability modes. Within the fluid-resonant category of cavity oscillation, most research has been carried out on rectangular geometries and where cylinders are considered, side branch and Helmholtz oscillators are most common. In these studi...