DEVELOPMENT OF A HIGH HEAT FLUX HEAT EXCHANGER

GAS-TO-LIQUID HEAT EXCHANGERS FIND APPLICATION IN NEARLY EVERY ENERGY CONVERSION AND PROCESS SYSTEM. HOWEVER, DUE TO LOW HEAT FLUXES, THEY ARE EXCESSIVELY LARGE AND EXPENSIVE. LOW HEAT FLUXES ARE CAUSED PRIMARILY BY LOW GAS-SIDE HEAT TRANSFER COEFFICIENTS. THE OBJECTIVE OF THIS STUDY IS TO DEVELOP A NOVEL FLUIDIZED BED HEAT EXCHANGER WHICH HAS SIGNIFICANTLY GREATER HEAT FLUXES THAN CONVENTIONAL HEAT EXCHANGERS. IT IS EXPECTED THAT THE ADDITION OF A FLUIDIZED BED ON THE GAS-SIDE WILL INCREASE HEAT FLUX BY AN ORDER OF MAGNITUDE. THE FLUIDIZED BED ALSO PROVIDES RESISTANCE TO FOULING. EXPERIMENTS WILL BE PERFORMED TO SELECT FLUIDIZED BED MATERIAL AND HEAT EXCHANGER GEOMETRY. CONSIDERATIONS IN BED MATERIAL SELECTION ARE MAXIMUM HEAT TRANSFER COEFFICIENTS AND LOW PRESSURE DROPS. HEAT EXCHANGER GEOMETRY SELECTION WILL BE BASED ON PREVENTION OF BED PARTICLE ELUTRIATION AND COMPACT AND SIMPLE CONSTRUCTION. AN ANALYTICAL MODEL WILL BE DEVELOPED TO PREDICT THE PERFORMANCE AS WELL AS AID IN THE DESIGN OF THE HEAT EXCHANGER. A PROOF-OF-CONCEPT MODEL WILL BE FABRICATED AND THE ANALYTICAL MODEL WILL BE VERIFIED. RECOMMENDATIONS FOR FUTURE WORK WILL BE MADE BASED ON RESULTS OF THIS PRELIMINARY STUDY.