Answer to Question #112310 in Mechanical Engineering for John Timothy

Question

Assume a large primary system that consist of a vessel containing warm water in the system with a temperature of 350,001k. An infinitesimal amount of its heat of 1050j is transferred to a secondary system consisting of a room air at a temperature of 350k. Consequently the water temperature drops to 349,999k. What is the entropy generation: A) If the system is cooled in air. B) If the heat removed from the primary system is used to run a cannot engine process and that rejected by the engine is transferred to the secondary system.

Answer 1

(A) Air temperature is at 350 K, Heat transfer= dQ= 1050 J

Entropy generation,

Here, in case of ambient condititon change in entropy will be zero

(B) As per the second case we know that for carnot heat engine

Q2=1049.99 J

and entropy generation