ISU engineers experiment with second blade on wind turbines


Iowa State University aerospace engineers Anupam Sharma (left) and Hui Hu stand behind 3D models of turbine prototypes. (Christopher Gannon/Iowa State University News Service)
Iowa State University aerospace engineers Anupam Sharma (left) and Hui Hu stand behind 3D models of turbine prototypes. (Christopher Gannon/Iowa State University News Service)

Nick Fetty | March 10, 2015

The old adage says that “two is better than one” and engineers at Iowa State University are studying whether this is true when it comes to the number of rotors on a wind turbine.

ISU aerospace engineering professor Hui Hu and aerospace engineering associate professor Anupam Sharma are studying ways to improve wind turbine efficiency. On many current models, the round-shape of the base of turbine blades reduces wind harvest by approximately 5 percent. Additionally, turbines that are downstream from others can lose 8 to 40 percent of energy generation.

“To try to solve these problems, we put a small rotor on the turbine,” Hu said in a news release. “And we found that with two rotors on the same tower, you get more energy.”

The research team has developed its dual-rotor turbine prototypes using 3D-modeling and other software applications. Through lab tests and computer simulations, the researchers saw an 18 percent increase in wind energy harvested.

Hu is testing his dual-rotor prototypes in ISU’s Aerodynamic/Atmospheric Boundary Layer Wind and Gust Tunnel to study power outputs, wind loads, and the physics of air flow on the different models. He has been assisted by postdoctoral research associate Wei Tian and doctoral students Zhenyu Wang and Anand Ozbay.

Sharma is focused on aerodynamic design of the dual-rotor models using high-fidelity computational fluid dynamics analysis and large eddy simulation. He has been assisted by doctoral students Aaron Rosenberg and Behnam Moghadassian.

Hu and Sharma were recipients of the Iowa Energy Center’s 2014 Renewable Energy Impact Award which provided them with $116,000 for their research. An additional three-year, $330,000 grant from the National Science Foundation will allow the researchers to continue their studies.

UI study finds that Midwest is experiencing more serious floods


Coralville, Iowa during the Flood of 1993. (Alan Light/Flickr)
Coralville, Iowa during the Flood of 1993. (Alan Light/Flickr)

Nick Fetty | February 12, 2015

The Midwest has seen a greater number of serious floods in recent decades compared to previous years, according to a report by researchers at the University of Iowa.

“It’s not that big floods are getting bigger, but that we have been experiencing a larger number of big floods,” said Gabriele Villarini, UI assistant professor of civil and environmental engineering and a co-author of the study.

The report – which was published this week in the journal Nature Climate Change – examined 774 stream gauges in 14 Midwestern states (Illinois, Indiana, Iowa, Kansas, Kentucky, Michigan, Minnesota, Missouri, Nebraska, North Dakota, Ohio, South Dakota, West Virginia, and Wisconsin). The researchers concluded that 34 percent of the sensors detected an increase in flooding events between 1962 and 2011. Nine percent of the gauges showed a decrease in flood events during that same time. The region including Illinois, Iowa, Indiana, Ohio, Missouri, and North Dakota experienced the greatest increase of flood frequency.

The authors wrote: “Most of the flood peaks in the northern part of the [Central United States] tend to occur in the spring and are associated with snow melt, rain falling on frozen ground, and rain-on-snow events.” However, the report “does not attempt to pinpoint precisely how climate change might be directly responsible for these increased flooding events.”

Serious floods have inundated the region in 1993, 2008, 2011, 2013, and 2014 and have caused more than $260 billion in damages between 1980 and 2013.

Funding for this research was provided by the U.S. Army Corps of Engineers Institute for Water Resources, the Iowa Flood Center, IIHR-Hydroscience & Engineering, and the National Science Foundation.

Scientists find evidence of human air pollution dating back to 1500s


The Adnes is the longest continental mountain range in the world stretching from Venezuela to Argentina. (Michael McDonough/Flickr)
The Adnes is the longest continental mountain range in the world stretching from Venezuela to Argentina. (Michael McDonough/Flickr)

Nick Fetty | February 10, 2015

Researchers have recently discovered evidence of air pollution believed to be from 16th century silver production in Bolivia.

The research team was led by Ohio State University professor Paolo Gabrielli with OSU’s Byrd Polar and Climate Research Center. The researchers discovered an imprint of smog high in metal content in an Andean ice cap in Peru but the source of the pollution is likely hundreds of miles east in present-day Bolivia.

The air pollution was believed to come from to come from silver refineries in the mountain town of Potosí. Prior to Spanish colonization, the Inca people mined silver in the area and at one point Potosí was the silver mining capital of the world. However with Spanish colonization came more efficient methods for mining silver which in turn led to greater amounts of air pollution. Much of the pollution from the silver mines consisted of lead, arsenic, and other materials and was believed to have occurred during between the 16th and 18th centuries.

The article was published in Proceedings in the National Academy of Sciences. The authors conclude: “This anthropogenic pollution of the South American atmosphere precedes the commencement of the Industrial Revolution by ∼240 y(ears).” Some scientists say that human-caused air pollution – “though agriculture, mining, fossil fuel production and other industrial activities” – has put us in a period known as Anthropocene. However scientists debate about when exactly this period began and Gabrielli’s recent findings would suggest that the period started earlier than previously thought.

The research was funded by the National Science Foundation (NSF) Paleoclimate.

National Science Foundation awards UNI $750,000 grant for Arctic research


Photo by banyanman; Flickr

CEDAR FALLS, Iowa — The National Science Foundation awarded a grant of $750,000 to the University of Northern Iowa for a project run by Andrey Petrov, assistant professor in the Department of Geography. The project is named RCN-SEES: Arctic-FROST: Arctic Frontiers of Sustainability: Resources, Societies, Environments and Development in the Changing North.

The project is based at the Arctic Social and Environmental Systems Research (ARCSES) Laboratory in the College of Social and Behavioral Sciences. As the leader of the project, UNI will serve as the national focal center of sustainability science research in the Arctic for the next five years.

Arctic-FROST builds an international collaborative network that teams together environmental and social scientists, local educators and community members to enable and mobilize research on sustainable Arctic development. The research is specifically aimed at improving health, human development and the well-being of Arctic communities.

 

On the Radio: University of Iowa Air Quality Grant


Photo by epSos.de; Flickr

This week’s On the Radio segment covers a study by the University of Iowa that was funded by a grant from the EPA. Continue reading for the transcript, or listen to the audio below.

Continue reading

ISU engineer receives $400,000 grant to optimize electric motor designs


Iowa State University assistant professor of electrical and computer engineering, Dionysios Aliprantis. Photo courtesy of Iowa State University.

Dionysios Aliprantis, an assistant professor at Iowa State University, received a five-year $400,000 grant from the National Science Foundation to fund his research on the optimization of electric motors and generators.

The grant is part of the NSF’s Faculty Early Career Development Program, and will fund Aliprantis’ work as he develops computer modeling technology that will help engineers craft electric motors into new, more powerful designs.

 “The goal is to get more power out of the same size motor,” said Aliprantis. “Or, that could mean getting the same power with a smaller motor.”

However, Aliprantis is not expecting a massive increase in performance.

“I’m looking for a little bit of increase, maybe 5 percent or 1 percent,” he said. “But multiply that number by the number of hybrid cars, let’s say, and you could get savings in the billions of dollars. The potential here could be huge.”

For more information, read the full Iowa State University news release.


On the Radio: Iowa universities receive major energy research grant


Listen to this week’s radio segment here or read the transcript below.  This week’s piece features a National Science Foundation grant that was awarded to Iowa’s three regent universities.

Iowa’s renewable energy research is about to reach a new level thanks to a National Science Foundation grant. Continue reading