TIDVG 3 - Thermo-mechanical study for future beams

1. TIDVG 3-Thermo-mechanical study for future beams C.Maglioni & F.Pasdeloup with contributions from: F.Leaux, I.Leitao 23rd July 2014

2. Outline • Reminder on the TIDVG • TIDVG operational limits • Simulations process • Temperature sensors TIDVG 3 – Thermo-mechanical study for future beam

3. Reminder on the TIDVG • Main Parts (CAD number ST0542558, Drawings SPSTIDVG0001) Section A-A Copper jackets (OFE, C10100 H02) Iron Shielding (EN-GJL-200) B B Tungsten blocks (Densimet 180) Copper blocks (OFE, C10100 H02) A A Beam direction Aluminum blocks (EN AW 6082 T6) Graphite blocks (2020 PT) + Titanium coating (Not yet considered in analysis) Section B-B Shielding Shielding’s cooling water pipes Copper core (Jackets+blocks) Aperture for the beam Core’s cooling water pipes TIDVG 3 – Thermo-mechanical study for future beam

4. Reminder on the TIDVG • Target Internal Dump Vertical Graphite installation history TIDVG 3 – Thermo-mechanical study for future beam

5. TIDVG operational limits • Previous studies showed that aluminum is the limiting factor of the TIDVG: allowed temperature and stresses are very low. • This fact might be confirmed by the damage observed during the endoscopy (to be confirmed by further studies). • Therefore the present studies are focused on the aluminum part only • A research on aluminum properties at high temperatures was done. • Newer and safer limits are proposed. TIDVG 3 – Thermo-mechanical study for future beam

6. TIDVG operational limits • The TIDVG 3 was submitted to 3 baked-outs. • Maintaining Al at high T for long time decreases permanently the strength and change the elastic properties. • We can estimate the average temperature of a bake-out at ~200°C. The total length of all bake-outs is more or less 40 days (~1000h) • At this temperature during a such long time we estimate that: • The tensile strength at room temperature decreases by 30%: 196MPa • The yield strength at room temperature decreases by 40%: 144MPa • To confirm this strength drop, an hardness test was done on an Al block of the TIDVG 3 (which previously underwent ~30 days of bake-out): an hardness decrease of 30% was observed. • Moreover the Yield Strength of Al drops instantaneously with increasing T: from room T to higher T: this means that operationally, Al is even more limited when it works at high T. TIDVG 3 – Thermo-mechanical study for future beam

7. TIDVG operational limits • Rather than a fixed limit on T, the new limits is a “dynamic” stress limit which is variable with T: • Nota: safety margin (uncertainties on the estimates) = 20% TIDVG 3 – Thermo-mechanical study for future beam

8. Simulation process • The simulation process is composed of two simulations: • A thermal analysis • A mechanical analysis • First step The thermal analysis is done on the whole TIDVG. This analysis is a multi-pulse analysis: transient analysis where the effect of each pulse is calculated in a same simulation. At the end of the simulation, we obtain a plot of temperature where each pulse is visible. TIDVG 3 – Thermo-mechanical study for future beam

9. Simulation process • Second step Mechanical simulations are carried out for a number of pulses, for the ones which appear to be already at elevated temperature. The safety factor is evaluated for each of them.The limit on the acceptable number of pulses is given by the number of pulses which remains below the acceptable limit in terms of maximum stress Safety factor = Stress calculated/0.8*yield strength Reminder: the yield strength is temperature dependent. TIDVG 3 – Thermo-mechanical study for future beam

10. Temperature sensors • Temperature sensors will allow to have a real-time temperature survey on the TIDVG. • We are limited to 8 sensors: limited by the number of available connections: • 2 sensors in the yoke: temperature on the outside of the copper core. • 4 sensors in the copper core: temperature inside the matter of the copper core. • 2 sensors on the cooling circuit: temperature of the cooling water. TIDVG 3 – Thermo-mechanical study for future beam

11. Temperature sensors • Temperature sensors in the yoke • Already present on the TIDVG 2: 2 in the upper yoke and 2 two in the lower yoke. They indicate the temperature on the copper core. • The yoke of the TIDVG 2 is reused: 2 of the 4 sensors will be connected. They are functionaland installed. Existing Temperature sensors Existing Temperature sensors TIDVG 3 – Thermo-mechanical study for future beam

12. Temperature sensors • Temperature sensors in the copper core • It was decided to install 4 sensors in the copper core: redundancy and equidistant data in the aluminum area: TIDVG 3 – Thermo-mechanical study for future beam

13. Temperaturesensors • Temperature sensors for the water • Two temperature sensors will be connected on the cooling circuit of the copper core: 1 sensor at the entrance, 1 sensor at the exit of one of the cooling circuits. Installation of the sensors TIDVG 3 – Thermo-mechanical study for future beam

14. Thank you for your attention TIDVG 3 – Thermo-mechanical study for future beam