Behind the breakthrough: A heat exchanger like no other
Heat exchangers are a key component to power generation and aviation systems that play a critical role in overall cycle efficiency. For decades, GE Research, GE Power, and GE Aviation have been working to evolve GE’s range of heat exchanger offerings by utilizing new designs with intricate features. These heat exchangers range in size from small kilowatt systems to larger megawatt systems for power plants.
Bolstering our efforts is the recent announcement that GE Research is leading a two and a-half year, $2.5 million project awarded by the Advanced Research Projects Agency–Energy (ARPA-E), to develop a 3D-printed compact heat exchanger with extreme capabilities. The new heat exchanger is to withstand temperatures that exceed 1,650°F at pressures greater than 3,600 psi. The Ultra Performance Heat Exchanger enabled by additive technology (UPHEAT) will enable cleaner, more efficient power generation in existing and next generation power plant platforms and aviation systems. In fact, successful completion of UPHEAT is projected to deliver a 4 percent improvement in thermal efficiency for supercritical CO2 power cycles while improving power output and reducing emissions. So, in a world where one additional megawatt of power and a tenth of a percentage point in efficiency can equate to millions of dollars in value, the potential value of UPHEAT is apparent.
So now that we know what UPHEAT will do, let’s talk about how GE Research plans to deliver.
As is the GE Research way, we’ve assembled a multidisciplinary team that includes experts in high temperature metal alloys, thermal management, and additive manufacturing.
“With 3D printing, we can achieve new heat exchanger design architectures previously not possible,” said Peter deBock, a principal thermal engineer for GE Research and project leader. “New ‘tri-furcating’ designs, developed by GE Research researchers Dan Erno and Bill Gerstler, split and recombine the fluid flow repeatedly while the other fluid moves through a similar structure in the opposite direction. These intertwined flows help to achieve superior heat transfer performance.”
Besides design innovation, in order to meet the high temperature performance, GE Research's Laura Dial will lead the application of a newly developed high-temperature-capable additive alloy for this heat exchanger. For such an application it is important to understand and account for how the properties of the alloy not only change during periods of operation when the temperature and pressure are high, but also how it is affected by the 3D printing process.
Luckily, high temperature metal alloys are commonplace among GE Research’s work, as we have spent decades developing the materials for GE’s power and jet engine turbine hot gas paths.
As a partner in the project, the University of Maryland is helping to develop parametric design and optimization models to further optimize heat exchanger performance. The Oak Ridge National Laboratory is also lending its expertise in corrosion science to test and validate the materials’ long-term performance.
The goal of the two and a-half year project is to develop and demonstrate the 3D-printed heat exchanger at full temperature and pressure capabilities.