Update and optimization of CEPC detector mechanical design - PowerPoint Presentation

1. Update and optimizationof CEPC detector mechanical designJi QuanApril 16, 2021

2. Outline: 1. General mechanical drawing in upgrade 2. Yoke design 3. Beampipe design 4. Summary and next plan

3. 1. General mechanical drawing in upgrade Layout 3… (Jan 20,2021)From a mechanical point of view,the detector includes:Heavy equipmentYokeHCALSolenoidECALLight equipmentTimingSETTPCSITVertexBeampipe●The design of heavy equipment is basically agreed●The light equipment still needs to be optimized. Improve the overall mechanical design of layout 3 detector selection

4. Improve the overall mechanical design of layout 3 detector selection Layout 3… (March,2021)……Light equipmentDCSi detector(five layers)VertexBeampipeWe did not have time to draw the new designof five layer Si disk onto the drawing.Certainly, new scheme is still being optimized.In the case of heavy equipment unchanged, light equipment has two options.

5. Improve the overall mechanical design of layout 3 baselineAs shown in the drawing above, we have marked the basic size of the determined equipment. ● Multi scheme comparison will may be the main theme of CEPC engineering design in the future ● From the engineering point of view, cooperate with the detector experts to find the best detection schemeSize distribution drawingIf physics, detector, software, and mechanicsall have a common baseline, it will be easier to communicate.

6. 2. Yoke designOptimization is carried out in three steps: --- Physical analysis and detection performance (1) Symmetricalstructure Spiralstructure Pros of spiral structure: Avoiding the blind area of μ detector

7. Optimization is carried out in three steps: --- Save money (2) Thickness: 600mmMuon: 3 layerHeight: 9600mmWeight: 920 tThickness: 1460mmMuon: 4 layerHeight: 12120mmWeight: 3180 tThickness: 600mmMuon: 5 layersHeight: 8520mmWeight: 760 tWeight reductionSave material costsOther costsDec 26, 2018Jan 16, 2020March 23, 2021

8. Optimization is carried out in three steps: --- Mechanical design (3) Spiral structureAbout 760 tDimensionLength: 8960mmOuter height: 8520mm Inner height: 7320mm8960In the direction of length, six trapezoidal vertical plateswere addedEach unit is made up of six iron plates, which can place five layers of muon detector

9. Deformation and stress of yoke under self weight Calculation conditions: Material --- T10 Load --- Self weight of yoke （760 t） Stress cloudDeformation cloudMaximum deformation: 1.65mmMaximum stress: 109MPaConclusion: Safety

10. Deformation and stress of yoke after installing all sub-detectors Calculation conditions: Material --- T10 Load --- Self weight of yoke + weight of the all sub-detectors self weight of yoke : 760 t weight of the all sub-detectors : 1600 t (estimate)1600 tons uniformly loaded onthe upper surface of two guide rails（Assuming: each rail is 200 mm wide）Schematic diagramof detector reloadingStress cloudDeformation cloudMaximum deformation: 1.37mmMaximum stress: 250MPaConclusion: SafetyBecomes smaller ?Why●The structure form ●The assumed load mode

11. 3. Beampipe designMarch 15, 20213.1 Optimization of general drawing (Center beryllium pipe with Φ28mm inner diameter)Progress: The basic structure has not changed:1) The beam pipe consists of four components：a, b, c and d2) On the beampipe, two detectors are installed --- Vertex and Lumical Improved aspects:1) Optimized the enlarged cooling channel structure of the central beryllium pipe2) Optimized the thickness of beryllium pipe3) Optimized process structure, easier to manufacture4) Simulated thermal analysis (based on the new heat load)d. Carbon fiber cylinderc. Air enlarge channelb. The central Be pipea. The extending Al pipeVertexLumiCalLumiCal

12. Optimization of enlarged cooling channel3.2 Optimization of central beampipeCone structureLadder structureStructural comparison design drawingOldNewOldNewStreamline comparison chartSimulation analysis shows: Under the ladder structure, the vortex is smaller and fewer, and the flow field is more stable.Conclusion: The improved ladder structure will greatly reduce the vibration of the beam pipe caused by unsteady flow

13. Relationship table between diameter, thickness and pressure: (Φ63mm)Relationship table between diameter, thickness and pressure: (Φ28mm)Relationship table between diameter, thickness and pressure: (Φ20mm)Optimization thickness of beryllium pipeThe optimization results show: Under the same flow channel pressure, The smaller the diameter, the smaller the thicknessIn the choice of thickness, we have two options ●Safety first inner diameter Φ28mm Thickness of outer Be pipe: 0.35 mm Thickness of inner Be pipe: 0.25 mm inner diameter Φ20mm Thickness of outer Be pipe: 0.25 mm Thickness of inner Be pipe: 0.20 mm ●performance first Thinner (As shown in the left table)The less the massThe thinner the Beryllium pipeThe better the performance

14. inner diameter Φ20mminner diameter Φ28mmTwo designs with different inner diameters and similar structures（Based on the optimization of cooling channel and thickness）In this structure,layer 1 and layer 2 of the vertex have the same length(Joao, Zenghao)Layer 1Layer 2Layer 1Layer 2Conclusion: According to different physical requirements,the mechanical aspect can be realized by similaror the same structure, but the parameters ordimensions are different.

15. The cone Al pipetotal area: 53726mm2 Z: 680.25W(2.45W/cm2) HZ: 2048.9W(4.8W/cm2)Straight Al pipetotal area: 7477mm2 Z: 68.79W(2.45W/cm2) HZ: 207.2W(2.27W/cm2)Be pipetotal area: 10556mm2 Z: 97.12W(0.92W/cm2)HZ: 292.52W(2.77W/cm2)Al pipetotal area: 61203mm2 Z: 749.04W(1.22W/cm2)HZ: 2256.1W(3.69W/cm2)April 8,2021 (Liu yudong)Optimized heat load of accelerator: (April 8, 2021)3.3 Calculation of overall temperature distributionThe total thermal loadZ: 2X(68.79+680.25) ≈ 1500 WHZ:2X(292.52+2256.1) ≈ 5100 W

16. Heat transfer calculation of beam pipe in Z mode (Q: 1500W)Calculation of model and condition0Be(Coolant: paraffin)Al(Coolant: H2O )Al(Coolant: H2O)Calculation model:laminarInlet of Be pipe: TEMP: 23℃ Velocity: 1.3 m/s Coolant: paraffinBe pipe parameters: length: 240 mm Inner Be THK: 0.5 mm Outer Be THK: 0.35 mm Gap: o.5 mmInlet of Al pipe: TEMP: 23℃ Velocity: 1.0 m/s Coolant: H2OTemperature distribution CloudResult: TEMP rise of Be pipe : 3.2 ℃ (between the inlet and the outlet) TEMP rise of transition: 13.3 ℃ TEMP rise of Al pipe : 6.3 ℃ Pressure drop of Be pipe : 19.8 kPa Pressure drop of Al pipe : 19.3 kPaNote: Pay more attention to the temperature of the outer surfaceMaximum TEMP of outer surface of Be pipe: 26.2 ℃Conclusion: Temperature rise and pressure drop are in a safe range.inletoutletinletoutletMaximum TEMP of outer surface of Al pipe: 29.3℃Maximum TEMP of transition: 36.3℃

17. Heat transfer calculation of beam pipe in HZ mode (Q: 5100W)Calculation of model and conditionBe(Coolant: paraffin)Al(Coolant: H2O )Al(Coolant: H2O)Calculation model:laminarInlet of Be pipe: TEMP: 23℃ Velocity: 2.0m/s Coolant: paraffinBe pipe parameters: length: 240 mm Inner Be THK: 0.5 mm Outer Be THK: 0.35 mm Gap: o.5 mmInlet of Al pipe: TEMP: 23℃ Velocity: 1.5 m/s Coolant: H2ODifferent calculation parameters: flow velocity is increasedTemperature distribution CloudResult: TEMP rise of Be pipe : 6.2 ℃(between the inlet and the outlet) TEMP rise of transition: 33.6 ℃ TEMP rise of Al pipe : 18.3 ℃ Pressure drop of Be pipe : 31.9 kPa Pressure drop of Al pipe : 37.7 kPaConclusion: Although the temperature rise and pressure drop have increased,they are still in the safe range of mechanical properties, and there isa possibility of optimization.inletoutletinletoutletMaximum TEMP of outer surface of Be pipe: 29.2 ℃Maximum TEMP of outer surface of Al pipe: 41.6℃Maximum TEMP of transition: 56.6℃Note: Pay more attention to the temperature of the outer surface

18. 4. Summary and next planSummary1) The overall layout frame of the detector is basically built2) The deformation calculation under the load only its own weight shows that the yoke scheme is feasible3) For the beam pipe design, the overall layout is relatively reasonable, but the design is relatively superficial. ●Only the issues of the heat dissipation and the strength are calculated. ●There are still many issues that have not been studied. ……Next plan1) Continue to strengthen communication and exchanges, deepen mechanical design work : a. General drawing b. Design requirements c. Never wait passively, carry out all possible work ……2) Perform comprehensive calculations to evaluate whether the yoke scheme is feasible with added magnetic field force3) Pre research on manufacturing of ultra-thin beryllium pipe ●Evaluate the feasibility of its processing, whether the vacuum and strength can meet the requirements Carry out more calculations and coupled calculations ●Evaluate the vibration issue of thin and light structures, and so on

19. Thanks!