Question

(Heat Transfer)
In a particular reactor design, a triangular lattice with pitch of 1.2 cm is being used for the reactor. The core is being designed with an 8 mm diameter fuel pellet (uranium nitride, k = 21 W/(m·K)) and a 1 mm thick HT9 steel cladding (k = 18 W/(m·K)). The gap is characterized by a gap conductance of 1300 W/m2K. A choice must be made between designing a sodium-cooled (at 1000 K) or pressurized, water-cooled (at 600 K) system. In either case, the flow speed would be 10 m/s and the maximum fuel (centerline) temperature must remain below 2600ºC.

Find:
(a) The maximum linear heat rate possible for a water-cooled design (in kW/m)

(b) The maximum linear heat rate possible for a sodium-cooled design (in kW/m)

Can someone help me, by showing the givens, equations, assumptions, properties and sketches needed to solve this problem.

Answer 1