HEAT TRANSPORT THROUGH A CORRODING METAL WALL OF CONCENTRIC TUBE HEAT EXCHANGER

Heat transport through a corroded carbon steel pipe in a double pipe heat exchanger in which aerated 0.1 N NaCl solution flowing in the annular space has been investigated. Experiments under isothermal and heat transfer turbulent flow conditions are carried out with Reynolds number range (5000-30000), at three bulk o temperatures (30, 40, and 50C⁰ ), and three heat fluxes (15, 30, and 45 kW/m C ).Mass transfer rates (corrosion rates) due to diffusion controlled oxygen reduction reaction have been determined by measuring the limiting current density,while rates of heat transfer have been determined by measuring surface temperature. Fouling due to corrosion deposits that form on heat transfer surfaces and its effects on heat and mass transfer processes have been studied through measuring the change of surface temperature and of limiting current density value with time for a period of 200hours.