Dr. Straatman’s research is in the general area of thermofluids, and includes engineering modelling, computational fluid dynamics (CFD), and experiment and application. His research foci include: modeling the transport of heat, mass and species in porous materials; and research on rotating flows. Applications in porous media include: enhanced convective heat transfer, moisture transfer and evaporative cooling, while applications in rotating flows include compressed air motors, vortex tubes, and energy extraction devices.
Dr. Straatman conducts fundamental research aimed at the development of models and algorithms that extend the capability for accurate simulation of fluid and heat flow. Of particular recent interest has been the development of accurate discretization techniques for conjugate heat/fluid flow modeling in fluid/porous/solid domains. Robust models have been developed to deal with transitions between fluid/porous regions and porous/solid regions. These interface formulations have extended the capability of our conjugate codes to deal with high Reynolds number flows with and without energy transfer and contact resistance.
Research on porous metals for convective enhancement includes a combination of laboratory experiments, engineering modeling and CFD. Experiments have been conducted to characterize the permeability and void-level heat transfer of various graphitized carbon foams. Engineering models have been developed to describe the internal structure of the porous material and the hydrodynamic and thermal performance of porous graphitic foam devices. Continued effort is directed at modification of the foam structure to optimize the balance of hydrodynamic and thermal performance of the carbon foam, and at multiphase convective heat transfer.
Recent effort has also been directed at the characterization of high-speed rotating flows, such as those seen in Ranque-Hilsch Vortex tubes (RHVT). A novel characterization of the Ranque-effect has been published in Physical Review letters, and has led to the development and patenting of a device that produces the cold output of a RHVT, but without the hot air output.