1. A PRELIMINARY THERMAL STUDY FOR L3 CGEM BOARD
G. Giraudo
CGEM-IT workshop IHEP Beijing March 2017

2. 2 TIGER CHIPS
0.8 W - 25 mm2
2 ANALOG REGULATORS
0.8 W - 6 mm2
CGEM-IT workshop IHEP Beijing March 2017
G.Giraudo INFN Torino

3. FE1 56x40 mm
FE2 56x30 mm
FE1+FE h≈16 mm
d≈4 mm
4 THERMAL PADS NEEDED
CGEM-IT workshop IHEP Beijing March 2017
G.Giraudo INFN Torino

4. A COPPER BOX (HEAT EXCHANGER) ADDED TO FE1 BOARD
THERMAL CONTACT THROUGH THERMAL INTERFACE MATERIALS (ELECTRICAL INSULATOR)
(THERM-A-GAP PARKER CHOMERICS, k=6.5 W/m∙K)
(THERMFLOW 777 PARKER CHOMERICS, k=7.7 W/m∙k)
DELIVERY & HEXAUST OF THE COOLANT THROUGH SS 316 TUBES & FITTINGS
ALL COMPONENTS ARE BRAISED
BOX FIXED ON FE1 BOARD WITH SCREWS (not shown)
WEIGHT < 50 g
CGEM-IT workshop IHEP Beijing March 2017
G.Giraudo INFN Torino

5. Tmax =21.5 oC WATER TIN18 °C 0.5 l/min ΔP=0.05bar
THERMAL LOAD=0.8
WATER TIN18 °C
0.5 l/min
ΔP=0.05bar
THERMAL LOAD=0.8 W
CGEM-IT workshop IHEP Beijing March 2017
G.Giraudo INFN Torino

6. DETAILED STUDY: VERY PRELIMINARY
TEMPERATURE DROP DUE
TO THE GEOMETRY ≈ 8 oC
CGEM-IT workshop IHEP Beijing March 2017
G.Giraudo INFN Torino

7. INLET
ΔP<0.2 bar
ΔT<0.3 °C
OUTLET
3 LINES IN - 3 LINES OUT
POSITION FOR THE Y MANIFOLDS MUST BE CONSIDERED IN THE WHOLE DESIGN.
BEST POSITION: AS CLOSE AS POSSIBLE TO THE HEAT EXCHANGERS
VOLUME SAVING SOLUTION: 1 LINE IN - 1 LINE OUT
9+9 HEAT EXCHANGERS GROUPED TOGETHER
ΔP≈0.6 bar, ΔT≈1 °C
CGEM-IT workshop IHEP Beijing March 2017
G.Giraudo INFN Torino

8. WHAT’S NEXT: PROTOTYPE FOR THE HEAT EXCHANGER
Validation of the FEM model
Feasibility
DESIGN OF THE WHOLE SYSTEM
Chiller, Valves, Flow regulators, …
INTEGRATION IN BESIII (L1 & L2 BOARDS?)
CGEM-IT workshop IHEP Beijing March 2017
G.Giraudo INFN Torino