HW4Prob3 - A PWR has dimensions and operating conditions...

Info icon This preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
Single Phase 41 1 A PWR has dimensions and operating conditions given below. Core Thermal Output 3817 Mw Fuel Height 150 inches Rod Pitch 0.506 inches Outer Clad Diameter 0.382 inches Power Peaking Factor 2.348 Axial Peak to Average Ratio 1.4 Number of Fuel Rods 56,876 Energy Deposited in Fuel 97 % Core Inlet Loss Coefficient 1.5 Core Exit Loss Coefficient 1.5 Grid Loss Coefficient 0.5 Number of Grids/assembly 8 Where the axial heat flux profile is of the form ′′ = ′′ + q z q z H e ( ) sin ( ) 0 π λ Upon shutdown, the fuel from this reactor is to be placed within the spent fuel storage pool. a) Assuming the inlet temperature to the fuel assemblies can be maintained at 80 F, what must be the minimum decay time such that no bulk boiling occurs within the highest powered assemblies? What if the pool temperature could be maintained at 100 F? b) What are the flow conditions at this time, i.e. laminar or turbulent? c) Assuming the Weisman correlation holds within the rod bundles, what must be the minimum decay time such that no boiling occurs on the rod surfaces in the highest powered assemblies? d) Natural circulation heat transfer coefficients for vertical cylinders are of the form m C(GrPr) Nu = where: number Nusselts k L h Nu c = number Grashof L ) T T ( g Gr 2 3 w 2 = μ βρ number Prandtl k C Pr p = μ
Image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon