Ultra-light carbon fiber structures: first test campaign

1. Enrico DA RIVA (EN-CV-PJ) Manuel GOMEZ MARZOA (EN-CV-PJ) 18th July 2012 Ultra-light carbon fiber structures: first test campaign WG4 Meeting - 18th July 2012

2. Outline • Thermal tests done over the structure already tested by the Bari team. WG4 Meeting - 18th July 2012

3. Setup description WG4 Meeting - 18th July 2012

4. Setup procedure • Assemble the circuit • Connect the sensors to the Data Acquisition System through ELMB cards • Existing channel configuration used: no need to recalibrate ELMB • Build up the PVSS panel • Connect the circuit bypassing prototype: flush water • Check the reading of the sensors • Connect prototype and flush water • Start measurements • Heater emissivity: ε=0.86 (for thermo camera) • Insulation placed over the PTs and connectors WG4 Meeting - 18th July 2012

5. Results • Six cases done, corresponding to the experiments done in Bari • An absolute power equal to 11.7 W applied to heater (see Bari presentation): • Rheater = 27.2 Ω • P = I2 R; I= (11.7/27.2)0.5 = 0.65 A • V = I R = 0.65*27.2 = 17.7 V • From case number 3 onwards, insulation was put over the aluminum connectors and the PTs at the piping • Temperature of the heater remains stable even when increasing the flow rate WG4 Meeting - 18th July 2012

6. Results – Thermal pictures Inlet/outlet Hotspot outside the stave cooling area 7.60 lpm 8.12 lpm 8.22 lpm 11.41 lpm 13.70 lpm 15.8 lpm Silicon WG4 Meeting - 18th July 2012

7. Results – Thermal pictures (Bari) WG4 Meeting - 18th July 2012

8. Results – Thermal pictures • Hotspots on the heater: 8.22 lpm Silicon Inlet/outlet • Hottest point is at the heater end, outside the cooled area (silicon) • Heater is supposed to be cooled there by the water at the pipe turn and the stave by thermal conduction along the heater. WG4 Meeting - 18th July 2012

9. Results – Thermal pictures • Temperature along three lines at the stave: 8.22 lpm Silicon Inlet/outlet T line 1 T line 2 T line 3 WG4 Meeting - 18th July 2012

10. Results • The first test (@7.6 lpm) can be neglected, the results do not follow the trend of the rest. • Noticeable decrease of silicon maximum temperature when transition to turbulent flow happens (~ 12 lpm). WG4 Meeting - 18th July 2012

11. Results • Difference in pressure drop with the expected theoretical values is due to the connectors, piping, etc. These losses can be considered as k*1/2*ρ*v2, where k is a constant dependent on the setting and can be calculated. • ΔT wall-water: establishes the margin of improvement by using a better cooling system for this setup: WG4 Meeting - 18th July 2012

12. Outcome • Experiences can be run fast and reliably. • Uncertainty: big • Sensors (PTs, NTCs, p sensors, flow meter). • Thermo camera: -/+4 oC below 100 oC • Systematic: depends on the setup (assembly of sensors, NTCs over heater). • Thermo camera shooting point: not fixed this time (reflections can appear). • Results qualitatively significant • Standardized setup necessary: • Stave support for quick replacement. • Tripod for thermo camera. • NTCs glued to the heater to enhance local contact. • Evaporative cooling system little improves thermal performance, but could ensure better T distribution. • Water tests can be repeated using the same absolute power as in the Bari experiences (13.7 W corresponding to 0.71 A current) WG4 Meeting - 18th July 2012

13. Enrico DA RIVA (EN-CV-PJ) Manuel GOMEZ MARZOA (EN-CV-PJ) 18th July 2012 Ultra-light carbon fiber structures: first test campaign WG4 Meeting - 18th July 2012