Iowa State Aerospace Engineering to lead $1 million NSF Grant

“The United States has a lot of general aviation flying around. From Personal aircrafts, to crop dusters, helicopters, and even UAVs.” – Assistant professor Peng Wei.

Iowa State University aerospace engineering assistant professors Peng Wei and Kristin Yvonne Rozier will lead a $1,000,000 grant from the National Science Foundation, creating a system to manage and monitor low-altitude air traffic.

Around the campus of Iowa State University, the sky can be bustling with helicopters, crop dusters, recreation planes, and personal unmanned aerial vehicles (UAVs). As technology improves, the sky is likely to get even more crowded. The increased traffic can present problems for pilots as well as people on the ground down below.

“In the United States, low-altitude is pretty busy compared with other countries,” said Peng Wei, an Iowa State assistant professor of aerospace engineering and principal investigator of a National Science Foundation grant. “We need to make sure we have a system to monitor this kind of traffic in both local airspace and also nation-wide so that we can have safe and efficient operations.”

Wei, along with Iowa State assistant professor Kristin Yvonne Rozier, University of Iowa professor Thomas Schnell, University of Michigan professor Ella Atkins, and

Lead investigator, Prof. Wei, will work with a number of other investigators, including Prof. Kristin Y. Rozier

George Hunter, principal data scientist at Mosaic ATM will create a way for the Federal Aviation Administration to maintain safe skies as they get more crowded. The team is specifically concerned with low-altitude, which the FAA defines as below 400 ft. above ground level.

“We will develop a system to monitor and manage and approve operations in low-altitude air traffic,” Wei said. “Our purpose is to give a software prototype to the FAA and also to the public to give the FAA more confidence as they enforce their own regulations and certifications.”

Wei likened the system to the way self-driving cars need structure in order to operate. “With autonomous cars, they can drive around but without traffic lights, stop signs, and intelligent signs on the roadway, they can’t function properly,” Wei said.

Three-step plan

The research team’s system will have three functions for UAV’s to follow. “The first one is called pre-departure flight planning,” Wei explained. “Before take off, we want to make sure the flight plan is safe and not conflicted with other air traffic.”

The second function is monitoring and alert. “After it takes off,” Wei said, “and even though it has followed the flight plan, what if another UAV malfunctions or birds or wind disrupts the flight plan? If everything goes to plan, we won’t require this step, but we need to detect a potential crash beforehand.”

“The final step is called emergency landing,” Wei said. “If the system recognizes a problem in the second step, the third step ensures that the aircraft can land safely or avoid further damage.”

The hope is to never need the second or third step of the system, but a plan will be ready just in case.

$1,000,000 award

The NSF is supporting the study with a three-year, $1,000,000 grant. Iowa State University, the lead institution, will coordinate with the other investigators throughout the process. During the first two years of the research, the team will create the working system and assemble all of the pieces together. In the third year, they will test the system and modify as needed on the campus of the University of Iowa.

Air traffic of the future

“Companies like Amazon and Google are talking about cargo airplanes to deliver medical supplies and other equipment,” Wei said, forecasting the future of air travel. “Uber and Air Bus are discussing autonomous flight or semi-autonomous flight to transport people.”

When you add those ventures on top of personal air travel and UAVs, the future of low-altitude air travel looks very busy. However, with a system in place, that air traffic will be much safer.

Engineering researchers collaborate to study pipeline corrosion

Ashraf Bastawros, professor of aerospace engineering, has received a $300,000 grant from the Department of Transportation’s Pipeline and Hazardous Materials Safety Administration (PHSMA). Along with Dr. Kurt Hebert from chemical engineering, Dr. Pranav Shrotriya from mechanical engineering, and Dr. Leonard Bond from the Center of Non Destructive Evaluation, Bastawros will develop advanced detection methods to calculate the physical and mechanical changes associated with early stress corrosion cracking in high strength pipeline steel.

Ashraf Bastawros, Leonard Bond, Kurt Hebert, and Pranav Shrotriya

The United States currently has almost 210,000 miles of liquid pipeline, with some of those pipelines ranging in age from 50-80 years old. As those pipelines age and endure corrosion from the soil
they start to crack, which can lead to shutting down the pipeline or even worse, leaks or explosions that can cause death and massive amounts of destruction.

“The trouble with stress corrosion is the limits of detection,” Bastawros said. “People discover these cracks and it is already too late. The cracks are small and can not be detected.”

To perform an inspection, technicians will shut down the pipeline and run a robotic device through the the line as it takes readings on the interior of the pipeline. At this point, the device will only be able to read large cracks in the steel.  

“Our approach is very different. Pipelines will have a lot of sub-surface changes. What we are trying to identify is at a very early stage, what are those sub-surface changes and if we can measure them.”

The group will investigate how to identify the precursors of a large crack in a pipeline. If they can find a way to identify a problem before the crack reaches tens of millimeters, they can remedy the problem before mass damage occurs.

Bastawros envisions that the progress made in pipeline research could be applicable for many other uses. “Corrosion is not prone only to pipeline, it is everything,” Bastawros said. “It is a multibillion-dollar annual loss. It includes infrastructure, airborne assets, marine assets, energy distribution lines, as well as nuclear power.”

If the group can find success increasing the lifespan of pipelines, future opportunities are endless.

Two professors and Phd student predict new phase transformation in physics journal

Valery Levitas_Phase Transformation Figure 3Valery Levitas, Schafer Professor and faculty member of aerospace engineering and of mechanical engineering, aerospace engineering PhD student Hao Chen, and Assistant Professor Liming Xiong published their work in Physical Review Letters, a highly ranked physics journal.

In the paper, the researchers predicted and studied a new type of first-order phase transformations. Levitas, Xiong, and Chen found that if they apply special different stresses along different directions during transformation, the phase transition will occur homogeneously.

The energy barrier between phases that exists during normal phase transformation, disappears during the new homogenous transition. This means that that the entire volume of the material can be homogeneously compressed/decompressed between two phases and there is no need for nucleation and growth.

“There are large stresses at interfaces that can damage material as phase grows during traditional transformations. When you do direct-reverse phase transformation many times, there can be material damage and energy dissipation and then it will stop working,” Levitas said.

The three researchers found that by applying special stresses from different sides, the transformation can occur without the drawbacks of traditional phase transformation. “There are no nuclei, there are no interfaces, there is no damage, and there is no energy dissipation,” Levitas said. 

With no damage or energy dissipation, the material can serve much longer and without requiring the need for extra energy. This may revolutionize numerous practical applications, such as for actuation and biomedical applications utilizing shape memory alloys and energy transformation with caloric materials.

The theoretical work is the first of it’s kind and paves the way for new fundamental and applied directions in phase transformations.

The Man Who Could Save The Planet

Aerospace Engineering Professor Bong Wie was recently profiled by Tom Lyden of KMSP Fox 9 in Minneapolis for his work with the Iowa State Asteroid Deflection Research Center. Wie, along with several graduate students, have developed a device that could save the planet from an asteroid hurtling towards Earth. The plan is currently under consideration from NASA at the Jet Propulsion Laboratory in Pasadena. 

Click here to read the entire article or watch the video below.




Characterization, modeling and uncertainty analysis of tornado wind and its effects on buildings

Partha Sarkar, PI


Investigator(s): Partha Sarkar (PI)

Award Amount: $250,000

Project Starts: June 1, 2014

Funding Agency: National Science Foundation

The objective of this project is to characterize, model and analyze uncertainty of tornado wind and its effects on buildings with an aim to enhance society’s resiliency to tornadoes. As direct measurement of tornado’s wind speed near the ground level is difficult to attain due to its unpredictable nature and destructive force, it is estimated based on observed damages to structures and non-structures in the EF Scale that is widely accepted in climatological study, risk analysis, and design of critical facilities. However, such damage-based methods are inherently subjected to a great degree of uncertainties contributed by multiple sources and critical knowledge gaps exist about spatial and temporal distributions of wind flow near the ground level and its interaction with natural and built environments. The advancement accrued from this research will link the tornado’s structure aloft to ground-level damages, thereby providing physics-based evidence critically needed for improving the current EF Scale. It will also allow better characterization of load effects under tornadoes and severe thunderstorms.

Tornado Simulator
2D-Ridge Model under the ISU Tornado Simulator

A framework for turbulence modeling using big data

Paul Durbin, PI


Investigator(s): Paul Durbin (PI)

Award Amount: $89,595

Project Starts: January 1, 2014

Funding Agency: University of Michigan

Assessments by NASA have identified deficiencies in the representation of turbulence as the most severe obstacle to the realization of predictive computational simulations of relevance to the aerodynamics community. The recent NASA Vision 2030 CFD report focused on the need for significantly improved turbulence models. Our research is on improving models for both Reynolds Averaged computation, and for Detached Eddy Simulation of turbulent flows, We also are working on models of transition from laminar to turbulent flow. We are pursuing a new approach to use data in developing models. A good many experiments, and high-fidelity computer simulations, have a stated objective of providing data for modeling. However, there has been little advance, over the last 40 years, in how to use data. A fundamental juggernaut has been the ambiguous connection between model variables and physically measurable quantities. In other words, our models have field variables that were devised for predictive purposes — and transport equations were contrived to generate them in computations — but they are not directly available in data. In our research program, adjoint based optimization methods are being used to extract fields of model variables from physical data. Then these derivative data are used to improve models — or to test the predictions of current models.

Visualization of vortices in a computer of a flow transitioning from laminar to turbulent.