Calendar: 1899-1900 Page 801

FACULTY OF SCIENCE CxllX 11 Define higher and lower pairing giving examples of each Explain the special advantages of each in machines -י II YEAR Paper II Six questions only to be attempted Distinguish between saturated and superheated steam Into what portions can the heat supplied to water to convert it into steam be divided Give the numerical values of each portion per lb of steam Describe some of the improvements which Watt effected in the steam-engine giving your notion of the economic value of each improvement you describe Explain what is meant by Carnot engine Rankine engine and show why each has been chosen as the Standard of Comparison for steam-engines What do you understand by Entropy Ί Draw and explain the temperature-entropy diagram for Carnot engine Rankine engine Assuming the heat produced by the combustion of lb of coal to be 14 000 's estimate the minimum con- sumption per horse-power hour in Carnot steam-engine the boiler temperature being 360 and the exhaust being atmospheric For an actual engine working between the same limits as the Carnot engine in question estimate in detail the probable losses in thermal units which would take place in boiler and engine per horse-power hour What is the meaning of isothermal expansion constant pressure expansion Adiabatic expansion Sketch and describe three different types of boiler and shew for what conditions each would be most suitable State any facts which you know bearing on the relative efficiency of the several types you mention boiler consumes 150 lbs of coal per hour and eva- porates at temperature of 270 970 lbs of water per hour the feed temperature being 60 What is its effi- ciency and if it has 500 square feet of heating surface how many 's per sq ft of heating surface per min are transmitted through the plates