1. What is the effect of increase in regeneration on steam rate?
a) steam rate increases
b) steam rate decreases
c) steam rate isindependent of regeneration
d) none of the mentioned
Explanation: More steam has to circulate per hour to produce unit shaft output
2. If h1 & h10 are the enthalpies at the inlet & at the exhaust, s1 & s10 are the enthalpies at the inlet & exhaust, the mean temperature of heat addition, Tml with regeneration is?
a) (h1 + h10)/(s1 + s10)
b) (h1 + h10)/(s1 – s10)
c) (h1 – h10)/(s1 + s10)
d) (h1 – h10)/(s1 – s10)
Explanation: The expression for mean temperature of heat addition is given as,
T = (h1 – h10)/(s1 – s10).
3. If Q represents the heat input, P represents the heat output; the efficiency n in terms of Q & P is given by?
a) n = QP
b) n = (Q-P)/Q
c) n = (P-Q)/Q
d) n = Q/(Q-P)
Explanation: The expression of efficiency in terms of heat input & output is given by,
n = (Q-P)/Q.
4.If q represents the work output, r represents the work input, Q represents the heat input, the efficiency n in terms of q & r is given by?
a) n = (q-r)/Q
b) n = ( q+r)/Q
c) n = (qr)/Q
d) n = (qr x qr)/Q
Explanation: The efficiency in terms of work input, work output & heat input is given by,
n = (q-r)/Q.
5. What is the effect of increase in steam rate on boiler size?
a) boiler size increases
b) boiler size decreases
c) boiler size is independent of steam rate
d) none of the mentioned
Explanation: Increase in steam rate increases by regeneration, i.e., more steam has to circulate per hour to produce unit shaft output. Hence, it increases boiler size.
6.In open feedwater heater __________
a) the extracted steam is allowed to mix with feedwater
b) feedwater flows through tubes and steam is condensed outside
c) steam flows outside tubes and feedwater inside
d) steam flows inside tubes and outside inside
Explanation: In a closed heater, the extracted steam is allowed to mix with feedwater and both leave the heater at a common temperature.
7. Expand TTD?
a) turbine temperature difference
b) total temperature difference
c) terminal temperature difference
d) turbine terminal difference
Explanation: Terminal temperature difference = saturation temperature of bled steam – exit water temperature
8. What are the advantages of open heater?
a) lower cost
b) high heat transfer capacity
c) high feedwater temperature
d) all of the mentioned
Explanation: Open heaters are cheap as compared to closed heaters, in closed heaters feedwater temperature is not high.
9. What do you mean by heater drip?
a) condensate
b) heater failure
c) extract
d) maximum temperature
Explanation: Saturated water at the steam extraction pressure.
10. Which of the following material can be used as a moderator?
a) Beryllium
b) Graphite
c) Heavy water
d) All of the mentioned
Explanation: A neutron moderator is a medium that reduces the speed of fast neutrons, thereby turning them into thermal neutrons capable of sustaining a nuclear chain reaction involving uranium-235.