College of Engineering News • Iowa State University

Iowa State awards state-funded grants to boost economy, develop new technologies

Hui Hu receives award to work with Goodrich Engine
Components Division of West Des Moines

Hui Hu, associate professor of aerospace engineering, will work with Goodrich Engine Components Division of West Des Moines to develop advance diagnostic techniques to quantify spray characteristics that will help develop the next generation of fuel nozzles for gas turbine engines.  Improving fuel nozzles will allow better fuel efficiency while maintaining operation requirements.

Legislation in the US, Europe and Asia require reductions in pollutant emissions in aviation, marine and power generation gas turbine engines, while transportation and energy demands globally continue to rely heavily upon the use of fossil fuels. In an effort to meet the needs of maximum energy efficiency, maintain operability requirements and minimize pollutant emissions, gas turbine combustion systems must be capable of achieving specific traits of local air/fuel ratios, mixing rates, and residence times. For gas turbine engines, this requires particular attention be paid to the fuel nozzle, as it is the key component initiating many of these traits.

In response to legislative directives and market trends, it is highly desirable to develop next generation fuel nozzles which can further optimize fuel preparation characteristics. This optimization will require advanced flow diagnostics which can provide a detailed description of the dynamic and thermodynamic behaviors of liquid sprays. It is well known that the process of breaking up or atomization of liquid fuel into droplets in the form of a fine spray plays a pivotal role in improving energy efficiency and suppressing pollutant formation, while meeting the operability requirements of the particular application. Significant product improvement can be achieved by having the ability to control the spray characteristics through the optimal design of fuel nozzles. Doing so requires a keen understanding of the physical mechanisms of breakup of liquid jets and sheets, atomization and evaporation of fuel droplets and air/fuel mixing in spray flow fields.

With the support of Grow-Iowa-Value-Fund program, Dr. Hu and his research group, in collaborating with Goodrich Engine Components Division (GECD) in West Des Moines, Iowa, will develop advanced flow diagnostic techniques to quantify details of the spray characteristics. The techniques to be developed will include a PIV/PLIF combined technique for the velocity field measurements of both air streams and fuel streams in spray flows; and a molecular tagging technique for the simultaneous droplet size, velocity and temperature measurements to characterize dynamic and thermodynamic behaviors of fuel droplets. The novel flow diagnostic techniques will be used to elucidate important microphysical processes in spray flows, such as the breakup of liquid jets and sheets, atomization and evaporation of fuel droplets, and air/fuel mixing for the development of next generation fuel nozzles to maximize energy efficiency while minimizing pollutant emissions, and maintaining the operability requirements.