Engineering Answers

By what percentage would the rate of absorption be increased or decreased by increasing the total pressure from 100 to 200 KN/m2 in the following cases:

a. The absorption of ammonia from a mixture of ammonia and air containing 10% of ammonia by volume, using pure water as solvent. Assume that all the resistance to mass transfer lies within the gas phase.

b. The same conditions as (a) but the absorbing solution exerts a partial vapour pressure of ammonia of 5 KN/m2. The diffusivity can be assumed to be inversely proportional to the absolute pressure.

By what percentage would the rate of absorption be increased or decreased by increasing the total pressure from 100 to 200 KN/m2 in the following cases: a. The absorption of ammonia from a mixture of ammonia and air containing 10% of ammonia by volume, using pure water as solvent. Assume that all the resistance to mass transfer lies within the gas phase. b. The same conditions as (a) but the absorbing solution exerts a partial vapour pressure of ammonia of 5 KN/m2. The diffusivity can be assumed to be inversely proportional to the absolute pressure.

an oxygen cylinder of volume 2.3 cubic foot has a pressure of 2200 psi gauge and is 21 degrees Celsius. Determine the mass of oxygen in the cylinder

A reheat cycle with two stages of reheating is executed, with steam expanding initially from 90 bar and 530 deg. C. The two reheater pressures are 10 bar and 0.6 bar, and the steam leaves each reheater at 480 deg. C. Condensation occurs at 0.03 bar. For an ideal cycle, find:

a. Q_a and e

b. For the engine, ignore the pressure drop through the reheaters, let the engine operate through the same states, and compute W and e.

c. What is the steam flow rate for an engine output of 20,000 kW?