Question

1. (10 marks total) Descriptive questions give brief answers in words. No calculations are required. You may write your answers in point form if you wish. (a) (1 mark) Under what conditions does a gas behave as an ideal gas? (b) (1 mark) In doing psychrometric calculations, water vapour is considered to be an ideal gas Explain why one can makeths assumption. (c) (1 mark) Define the adiabatic flame temperature. (d) (1 mark) In a steam power cycle, what is the diffèrence between an open feedwater heater and a closed feedwater heater? (e) (2 marks) Sketch a gas turbine cycle with regeneration and explain how a regenerator increases cycle efficiency (f) (2 marks) Sketch a gas compressor with intercooling and sketch its processes on a T-s diagram. Explain why intercooling reduces compressor work. (g) ( mark) Name three ways to increase the efficiency of a Rankine (steam power) cycle. (h) (1 mark) How does a dehumidification process work? Sketch a T-s diagram to explain the changes of state that occur during dehumidification

Answer 1

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2 2' 21-3→ 2nd Stay sser. the reducho g noo me ェ//o in Caese g- udegineinf , Three w icle to feedim tne feed- ole heater D hir bsiles れ
b) Water vapour behave as an ideal gas at a pressure below 10 Kpa.