Afuel oil is burned with air in a boiler furnace. the combustion produces 813 kw of thermal energy, of which 65% is transferred as heat to boiler tubes that pass through the furnace. the combustion products pass from the furnace to a stack of 550∘c. water enters the boiler tubes as a liquid at 30∘c and leaves the tubes as saturated steam at 20 bar absolute.

(a) calculate the rate (kg/h) at which steam is produced.

(b) use the steam tables to estimate the volumetric flow rate of the steam produced.

(c) repeat calculation of part (b), only assume ideal-gas behavior instead of using the steam tables. would you have more confidence in the estimate of part (b) or part (c)? explain.

(d) what happened to the 35% of the thermal energy released by the combustion that did not go to produce the steam?