Problem
A boiler evaporates 8,000 kg/h from feedwater enthalpy 420 kJ/kg to steam enthalpy 2,760 kJ/kg. Calculate equivalent evaporation from and at 100°C using latent heat 2,257 kJ/kg.
Given Data
Write all quantities in consistent SI units before substitution.
Formula and Solution
Factor of evaporation = (2,760 − 420)/2,257 = 1.0368. Equivalent evaporation = 8,000 × 1.0368 = 8,294 kg/h.
Engineering Check
Check units, magnitude and physical meaning. State any simplifying assumptions and avoid mixing mass flow per hour with energy per second.
Practice Variation
Repeat the problem after changing one input by 10% and explain how the answer responds.