E. Da Riva/M. Gomez Marzoa1 CFD Weekly Meeting - 3rd June 2012 ITS Upgrade: Cooling progress Enrico DA RIVA (EN-CV-PJ) Manuel GOMEZ MARZOA (EN-CV-PJ) 3 rd June 2012

E. Da Riva/M. Gomez Marzoa2 CFD Weekly Meeting - 3rd June 2012 Light structure thermal studies  Two configurations concerning the wrapping of the Carbon Fiber around the pipes were built: 1.A low-pitch configuration, where a carbon fiber strip was set along the pipes to give mechanical strength (also helps from the thermal point of view)  The CF is wrapped over the pipe and the CF strip with a ~40 deg angle. 2.A high-pitch configuration, with the Cfwarpped over the pipe (with no extra CF strip within).  CF wrapped over the pipe with a ~24 deg angle. Overview

E. Da Riva/M. Gomez Marzoa3 CFD Weekly Meeting - 3rd June 2012 Light structure thermal studies  For each geometrical configuration, thermal studies were conducted for two cases: A.Silicon glued directly to the CF conforming the mechanical structure. B.A high-conductivity Thornel K1100 carbon fiber plate is glued to the mechanical structure and the silicon is glued to the plate.  Materials:  Carbon Fiber:  K13D-2U CF: k Fiber = 450 W m -1 K -1 ; k Transv = 1.2 W m -1 K -1  Plate (second case): Thornel K1100 CF: k Fiber = 550 W m -1 K -1 ; k Transv = 1.2 W m -1 K -1  Glue: k = 1 W m -1 K -1  Pipe (Kapton): k= 0.12 W m -1 K -1  Silicon: k = 150 W m -1 K -1 Overview

E. Da Riva/M. Gomez Marzoa4 CFD Weekly Meeting - 3rd June 2012 Light structure thermal studies Boundary conditions  Imposed heat transfer coefficient in the cooling pipe, supposing water flowing inside at 0.5 m s -1 (laminar flow) and 15 °C.  Considering, for the stave:  Correlations predict a HTC of 1646 W m -2 K -1  Rest of surfaces: adiabatic/connected  Symmetry considered d_i [mm]m [g/s]m [kg/s]L [m] Vel [m/s]ΔT in-outRe Δp lam [bar] Δp Pethukov [bar] HTC (lam) f LAMA pipe ΔT wall- water (LAM) q0.5W cm -2 w16mm L250mm Q= 20 W

E. Da Riva/M. Gomez Marzoa5 CFD Weekly Meeting - 3rd June 2012 Light structure thermal studies Low-pitch cases configuration (1A and 1B) CF wrapping Silicon Thornel Plate (case B) Glue CF strip

E. Da Riva/M. Gomez Marzoa6 CFD Weekly Meeting - 3rd June Low-pitch configuration A. No plate case: temperature map [°C] q’= 0.3 W cm -2

E. Da Riva/M. Gomez Marzoa7 CFD Weekly Meeting - 3rd June Low-pitch configuration A. No plate case: temperature map [°C] q’= 0.3 W cm -2  Hotspot in the silicon

E. Da Riva/M. Gomez Marzoa8 CFD Weekly Meeting - 3rd June 2012 B. Thornel K1100 plate case: temperature map [°C] q’= 0.3 W cm Low-pitch configuration

E. Da Riva/M. Gomez Marzoa9 CFD Weekly Meeting - 3rd June 2012 B. Thornel K1100 plate case: temperature map [°C] q’= 0.3 W cm Low-pitch configuration  Hotspot in the silicon

E. Da Riva/M. Gomez Marzoa10 CFD Weekly Meeting - 3rd June 2012 High-pitch cases configuration (2A and 2B) 2. High-pitch configuration

E. Da Riva/M. Gomez Marzoa11 CFD Weekly Meeting - 3rd June 2012 A. No plate case: temperature map [°C] q’= 0.3 W cm High-pitch configuration

E. Da Riva/M. Gomez Marzoa12 CFD Weekly Meeting - 3rd June 2012 A. No plate case: temperature map [°C] q’= 0.3 W cm -2  Hotspot in the silicon 2. High-pitch configuration

E. Da Riva/M. Gomez Marzoa13 CFD Weekly Meeting - 3rd June 2012 B. Thornel K1100 plate case: temperature map [°C] q’= 0.3 W cm High-pitch configuration

E. Da Riva/M. Gomez Marzoa14 CFD Weekly Meeting - 3rd June 2012 B. Thornel K1100 plate case: temperature map [°C] q’= 0.3 W cm -2  Hotspot in the silicon 2. High-pitch configuration

E. Da Riva/M. Gomez Marzoa15 CFD Weekly Meeting - 3rd June 2012 Conclusions  The CF strip, oriented with the fiber along the Kapton pipe, provides an overall higher thermal performance, as a result of maximizing the pipe-wrapping fiber contact area.  Silicon maximum temperature is lower  Profit of a bigger surface of the pipe.  Including the Thornel K1100 CF plate in between the wrapping fiber abd the silicon helps to spread the heat and achieve a better temperature uniformity in the silicon detector.

E. Da Riva/M. Gomez Marzoa16 CFD Weekly Meeting - 3rd June 2012 ITS Upgrade: Cooling progress Enrico DA RIVA (EN-CV-PJ) Manuel GOMEZ MARZOA (EN-CV-PJ) 3 rd June 2012