1. New Plate Baffle Water Flow

2. Quick Simulation Use triangular prism as rough estimate of a vane Uniform heat flux on each surface –600 kWm -2 on end face (highest flux at cutback… average would be much less!) –20 kWm -2 on side faces –Symmetry at other end, stagnant air convection on top surface See what temperature copper gets to (Next, use better vane shape and heat flux)

3. Flow Estimates Total power, P, to be removed from 355mm long prism ≈ 2 kW Water mass flow rate,, per pipe = 0.157 kgs -1 (assuming flow speed = 2 ms -1 = 9.42 L min -1 ) Estimated temperature rise, ΔT, of cooling water ≈ 3 °C Pipe length, L, within copper = 2.1 m Average water flow rate v av = 2 ms -1 Pipe diameter, D H = 10 mm Estimated pressure drop, Δp = 0.12 Bar Nusselt number, N u, of water flow = 144.2 Thermal conductivity of water, k = 0.6 Wm -1 K -1 Estimated heat transfer coefficient = 8650 Wm -2 K -1

4. Very crude approximation of vane shape and input heat flux, but overall temperature distribution is comparable to previous, more accurate simulations (small image above)

5. Average Outlet Water Temperature = 18 °C Inlet Water Temperature = 15 °C Racetrack path of water flow repeatedly redistributes heat from primary heat input region on left to cooler region on right. Water absorbs a lot of heat Water becomes cooler again

6. Average HTC = 9000 Wm -2 K -1 Higher HTCs on thinner channels where water flow is faster

7. Sharp transitions between layers increase the water pressure significantly compared to estimate for smooth cooling channel

8. Comparison of Results PropertyHand estimateANSYS CFD Result Mass flow rate0.157 kgs -1 (9.42 Lmin -1 ) 0.1545 kgs -1 (9.27 Lmin -1 ) Average water flow2 ms -1 1.914 ms -1 Maximum water flow 5 ms -1 (desired upper limit) 4.227 ms -1 Total Pressure0.12 Bar0.375 Bar Average HTC8650 Wm -2 K -1 9000 Wm -2 K -1 Water temperature rise 3 °C Simulation matches back-of-the-envelope calculations (again… well done ANSYS!) Copper temperature similar to previous simulations with different flow  Good To do now: try a more accurate model and put in a squirt nozzle