This Grant Opportunities for Academic Liaison with Industry (GOALI) project will focus on heat exchangers made of thin-walled co-extruded nylon tubing woven into tube bundles. Polymer heat exchangers are an attractive alternative to metal heat exchangers in large-volume applications where corrosive fluids are present, weight is important, or integration with other components is desirable. The collaborative GOALI project of the University of Minnesota, DuPont, and ThemoKing aims to solve key material, design and manufacturing problems that must be addressed before polymer heat exchangers can be successfully commercialized for cooling automotive and truck components and refrigerated containers. Fundamental issues that will investigated are failure mechanisms in the coextruded tubes, design and manufacture of tube manifolds, and characterization of convective heat transfer in unique woven tube bundles. Tube failure, particularly delamination, will be characterized in terms of the relationship between loads, strain, temperature and time. A modification of laminated plate theory will be applied to predict failure in tubing of various layered constructions from limited creep/DMA data. Design guidelines and manufacturing techniques for tubesheet and tube bundle manifolds will be established using analytic and experimental approaches. Experimental measurements of heat transfer in prototype air-to-liquid heat exchangers will result in generally applicable Nusselt number heat transfer correlations that can serve as the basis for design of woven tube bundles.
The models and design tools resulting from this research are expected to play a key role in the successful commercialization of polymer heat exchangers for the transportation industry.
