1 / 15

Air Cooling by means of carbon fiber structure

Enrico DA RIVA (EN-CV-PJ) Manuel GOMEZ MARZOA (EN-CV-PJ) 27 th June 2012. Air Cooling by means of carbon fiber structure. Outline. Air cooling: unites cooling performance and material budget. Triangular carbon fiber structure considered, using it for cooling .

vienna
Download Presentation

Air Cooling by means of carbon fiber structure

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Enrico DA RIVA (EN-CV-PJ) Manuel GOMEZ MARZOA (EN-CV-PJ) 27th June 2012 Air Cooling by means of carbon fiber structure WG4 Meeting - 27th June 2012

  2. Outline • Air cooling: unites cooling performance and material budget. • Triangular carbon fiber structure considered, using it for cooling. • Similar solution as the STARexperiment: 8 m s-1 , 0.1 W cm-2 • Advantages: • Simple cooling system • No extra material added • Disadvantages: • Adequate for low power densities • Restricted air velocity (vibrations) • Sensor temperature uniformity STAR Experiment • Models studied by means of CFD: • Single stave: Thermal fin performance • A two-layer model of the ITS Barrel WG4 Meeting - 27th June 2012

  3. Overview • Single stave: Thermal fin performance • Geometrical features: • CF: 130 µm thick • Si: 50 µm thick • Stave: 300 mm long • Material properties: • CF: k = 620 W m-1 K-1 (assumed to be isotropic) • Si: k = 150 W m-1K-1 • Boundary conditions: • Tair Inlet = 14 °C • vInlet • q’Silicon OUT 268 mm 15 mm IN Si sensor WG4 Meeting - 27th June 2012

  4. Single stave: CFD Analysis 0.3 W cm-2, 10 m s-1 Temperature silicon [°C] Tmax= 60 °C Temperature CF [°C] WG4 Meeting - 27th June 2012

  5. Single stave: CFD Analysis 0.3 W cm-2, 20 m s-1 Temperature sensor [°C] Tmax= 43 °C Temperature stave [°C] WG4 Meeting - 27th June 2012

  6. Single stave: conclusions • Only the case with 0.1 W cm-2 and 10 m s-1 would fulfill the detector thermal requirements for a single stave • The behaviour of the stave as a thermal fin is seen • Thermal performance improved when cooling from both sides of the triangular shape. 0.1 W cm-2, 10 m s-1 Tmax= 30 °C Stave heat flux [W m-2] q’ = 0.3 W cm-2, 10 m s-1 WG4 Meeting - 27th June 2012

  7. Two-layer model: description • 2. A two-layer model of the ITS Barrel: • Only a section including two triangular shapes was modeled • Assumed a 30 mm chamber at the barrel end as recirculation zone • Mesh: ~ 5 million cells • Turbulence model: SST k-ω, Low-Re corrections 30 mm L2 Beam Pipe L1 WG4 Meeting - 27th June 2012

  8. Two-layer model: description • Sector of the ITS barrel was modeled by means of CFD • Two inlet ducts and one outlet per layer • Simplified geometry built from the mechanical CAD design • Total length stave: 300 mm (268 mm sensor) + recirculation region • Material properties: • CF: • T300 fabric (biaxial thermal conductivity) • kPlanar = 400 W m-1K-1 • kTransv= 1.2 W m-1K-1 • Thickness: 130 µm (triangles and separation layers) • Si: k = 150 W m-1K-1 • Boundary conditions: • vInlet = 10 m s-1 • q’Sensor = 0.3 W cm-2 • Tair Inlet = 14 °C WG4 Meeting - 27th June 2012

  9. Two-layer model: CFD study 0.3 W cm-2, 10 m s-1 Magnitude of air velocity in a plane along the volume [m s-1] Pressure drop: L1 = 325 Pa, L2 = 306.28 Pa WG4 Meeting - 27th June 2012

  10. Two-layer model: CFD study 0.3 W cm-2, 10 m s-1 Temperature silicon L1 [°C] Temperature silicon L2 [°C] WG4 Meeting - 27th June 2012

  11. Two-layer model: CFD study 0.3 W cm-2, 10 m s-1 Heat flux silicon in triangle L2 [W/m2] Heat flux to outlet L2 [W/m2] WG4 Meeting - 27th June 2012

  12. Two-layer model: CFD study 0.3 W cm-2, 10 m s-1 Temperature CF stave L1 [°C] WG4 Meeting - 27th June 2012

  13. Outcome • The silicon is only cooled with the air flow inside the triangular duct, because voutlet duct is small. • Possible solutions: • Increase air velocity • Vibration & shear stress increase • Equalize inlet/outlet sections: guarantee high velocity at outlet ducts • Use different cooling fluid • Laminar flow and small molecule: no stresses over mechanical structure • Still, cooling from both sides of the sensor has to be guaranteed AIR HELIUM WG4 Meeting - 27th June 2012

  14. Outcome • The silicon is only cooled with the air flow inside the triangular duct, because voutlet duct is small. • Possible solutions: • Increase air velocity • Vibration & shear stress increase • Equalize inlet/outlet sections: guarantee high velocity at outlet ducts • Use different cooling fluid • Laminar flow and small molecule: no stresses over mechanical structure • Still, cooling from both sides of the sensor has to be guaranteed • Solution to be used for low q’ AIR HELIUM WG4 Meeting - 27th June 2012

  15. Enrico DA RIVA (EN-CV-PJ) Manuel GOMEZ MARZOA (EN-CV-PJ) 27th June 2012 Air Cooling by means of carbon fiber structure WG4 Meeting - 27th June 2012

More Related