Research Facilities

(Please click on add to see available positions)

The left picture shows a 64-node Beowulf cluster and the right picture shows an anachoic chamber.

Current Research Projects

Sir James Lighthill at Brown University, 1984

 

The goal of this research effort is to address the problem of rocket/jet noise using a steady state CFD solution. The well-known MGB model fails to capture the shape of the spectrum and the directivity pattern without adjusting numerous empirical constants. It is Fanny' goal to improve the current state of the art by using new turbulence models and information obtained from LES computations. This work is performed as part of her Ph.D. research requirement and is being funded through an SBIR Phase II from NASA Stennis.

The left picture shows an X-33 engine hot-fire and the right picture shows a CFD plume. The above picture are a courtesy of NASA MSFC.

 

With the expected rapid growth of air transportation coupled with the growth of airport communities, aircraft propulsion system noise is a major concern. Various control technologies, passive and/or active, are being tested to reduce jet noise. One of these techniques involves injecting water in the jet plume. The current research effort will involve the use of state of the art CFD techniques to investigate the various parameters involved in water injection. The goal will be to find optimal parameters to maximum noise reduction and prove the viability of the technique for actual flight tests. This investigation will be carried-out by Ricky Brown as part of his Ph.D. research project requirement.

The left and right picture show water droplets in a launch vehicle plume (from the work of Francisco Canabal).

 

Acoustics is a bi-product of unsteady turbulent flows, therefore modeling of unsteady turbulent flows is critical. In this study, a new class of turbulence models known as Partially Averaged Navier-Stokes (PANS) are tested for applications that are important to noise emissions and structural vibrations. In particular, the k-omega PANS is used for wall-bounded flow applications. This research will be carried-out by Mahmoud Zreik as part of his Master thesis requirement.

The left picture shows a turbulent flow past a backward facing step and the right picture shows a turbulent flow over a smooth square cylinder.

 

Acoustic induced combustion instabilities are known to exist in many practical engineering problems, such as rocket engines, internal combustion chambers... etc. These instabilities can lead to engine malfunction and shutdown. To date, little is understood about the origin of these instabilities. Therefore, the only control device that has successfully reduced the effects of these instabilities is an adequately designed Helmholtz resonator. Caroline Hood is working on this project as part of her Master degree requirement.

The left picture shows the effect of adding a passive device to a combustion chamber and the right picture shows the turbulent flow in the chamber.

 

Continuous carbon dioxide removal from cabin air is a critical life support system function on manned space missions. On the International Space Station (ISS), the carbon dioxide removal assembly (CDRA) has been designed and tested to be capable of maintaining a cabin concentration of less than 0.7% in atmospheric pressure. Lower concentrations are desirable to enable human research opportunities. Off-design operation is also under consideration to reduce power consumption during power critical operations. Theoretical models will be developed and solved numerically to analyze off-design operational modes. Other applications of these adsorption simulations are to analyze sorption pump design for CO2 recovery and analyze design of a system for in-situ recovery of CO2 from the Martian atmosphere. These models will be developed and solved by Jim while working towards his Ph.D. degree.