Dissolved oxygen is being gassed off water using pure nitrogen gas as the sparger in a wetted wall column. At one point in the column, the oxygen content of the water is 6.3 mg/L. The liquid and gas side local mass transfer coefficients were determined as 0.0638 m/s and 0.0998 mol/m² -s-atm, respectively. If the Henry's Law constant for the system is 770 atm/M at 27.5°C and 1 atm, what percent of the resistance is offered by the gas phase? O 45.4% O 71.0 % O 56.5% 54.6 %

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According to nature of flow, convective heat transfer is classified into natural convection and forced convection. By taking specific examples, explain how the natural convection and forced convection arises in them.

5. Porous Flow Problem: Suppose we have a horizontal catalyst pack of spheres 1 mm in diameter, which pack at a porosity of 40 %. The pack is in a cylindrical tube 1 m long, and 8 cm in diameter. Some questions... a. How many spheres (roughly) would fit in the pack. (You can calculate V cylinder occupied by spheres/volume of a sphere .. although this is not exactly correct) b. What is the pressure drop needed to flow water through the pack at a nominal velocity (Q/A) of 0.05 m/s. Use Ergun Equation. c. Would this be laminar or turbulent... or does that even apply? d. What would the permeability be if we applied Darcy's Law (ignoring whether it is laminar or turbulent) 6. For the problem above, if the sphere specific gravity was 0.7, what flow rate (Q) would be required to lift the bed upwards if the orientation were vertical? (Note .. we have to lift the pack and the fluid in it.. not just the pack. So find Q where AP x A = Weight of pack and fluid).