Thermal Shield Connection Study Niklas Templeton 15/02/16

Thermal Shield Connection Study Updated connection configuration FE Model Steady State Thermal Results Welded shield Pipe with integrated connection Separate connection Al6061 Pipe SS316 Pipe Static Structural – Thermal Contraction Pipe and Panel Stress Comparison

FE Model – Connection Proposal 2 Floating clamp connections for FPC thermalisation Top circuit modified for assembly purposes 9 Lateral Fixed connection points (100 mm long) FPC load applied directly to clamp HOM Coax heat load applied at Panel Interface

Boundary Conditions Heat Loads: see table Pipe 50-70 K Gradient Intercept Heat Load (W) Qty Total (W) FPC 55 2 110 HOM Coax 12.0 6 72 Blades 7 4 28 Tuner 5 10 CWT 1 222 Heat Loads: see table Pipe 50-70 K Gradient Radiation: 1.7 W/m2 Flux applied all external surfaces Titanium Fixations: T=295 K at OVC interface Material Properties: see graph All thermal contact connections: 200 W/m2K (unless otherwise stated) for conservative results Assuming no contact between pipe and panels other than at connection points

Shield Thermal Gradient Welded Connections Pipe Connection Shield Thermal Gradient T min (K) T max (K) Welded 50.3 90.1 Ideally bond between Pipe-Fillet & Fillet-Panel Conclusions: T max is concentrated at HOM Coax 6, can be improved. Results are promising Connection configuration to be carried forward Ease of manufacture & assembly Shield not over-constrained

Connection Comparison 3. Separate Connector Al Pipe* 1. Welded Connection 2. Integrated Connector* 4. Separate Connector SS Pipe* Ideally bond between Pipe-Fillet & Fillet-Panel Contact resistanc between Connector-Panel Contact resistance between Pipe-Connector & Connector-Panel 2. *Contact area scaling factor required Estimated as 1:3

Thermal Contact Conductance 167 W/m2K 250 W/m2K 500 W/m2K Thermal Contact Resistance Measurements for indirectly cooled SR Optics, B Fell & K Fayz, Daresbury Laboratory 2013

2. Integrated Connector 666.7 W/m2 Contact resistanc between Connector-Panel Pipe Connection Thermal Contact Conductance (W/m2K) Scaled Thermal Contact Conductance (W/m2K) Shield Thermal Gradient T min (K) T max (K) Welded - 50.3 90.1 Integrated Connector 2000 666.7 58.8 96.4 1500 500.0 61.4 98.4 1000 333.3 66.3 102.3 500 166.7 77.7 113.7 166.7 W/m2

3. Separate Connector Al Pipe Pipe Connection Thermal Contact Conductance (W/m2K) Scaled Thermal Contact Conductance (W/m2K) Shield Thermal Gradient T min (K) T max (K) Welded - 50.3 90.1 Integrated Connector 2000 666.7 58.8 96.4 1500 500.0 61.4 98.4 1000 333.3 66.3 102.3 500 166.7 77.7 113.7 Non-integrated connector (Al Pipe) 64.6 101.1 68.7 104.5 75..2 111.3 93.1 130.7 666.7 W/m2 Contact resistance between Pipe-Connector & Connector-Panel 166.7 W/m2

4. Separate Connector SS Pipe Pipe Connection Thermal Contact Conductance (W/m2K) Scaled Thermal Contact Conductance (W/m2K) Shield Thermal Gradient T min (K) T max (K) Welded - 50.3 90.1 Integrated Connector 2000 666.7 58.8 96.4 1500 500.0 61.4 98.4 1000 333.3 66.3 102.3 500 166.7 77.7 113.7 Non-integrated connector (Al Pipe) 64.6 101.1 68.7 104.5 75..2 111.3 93.1 130.7 Non-integrated connector (SS Pipe) 67.8 105.1 96.2 137.8 666.7 W/m2 Contact resistance between Pipe-Connector & Connector-Panel 666.7 W/m2

Engineering Data – Thermal Expansion

Cool Down Deformation Welded Shield

Cool Down Deformation Welded Shield

Cool Down SS Pipe

Cool Down SS Pipe