DOE Review of VTX upgrade detector for PHENIX

DOE – Review of VTX upgrade detector for PHENIX Mechanics: Walter Sondheim - LANL Mechanical Project Engineer Walter Sondheim 6/2/2009 1

VTX global model: “Big Wheel” regions in gas enclosure, where all read out cards are located Barrel mounts Space Frame central truss FVTX detector support cage* Pixel layer 1 ladders, followed in R by layer 2 then strip layers 3 &4 Isolation mounts (3) flexures View not showing FVTX detector* Walter Sondheim 6/2/2009 2

Outline: • Status of global mechanical design for VTX detector; – HYTEC’s Deliverables • Making the transition from design to production; materials, fabrication techniques, tolerances – Pixel ladders • Staves; in production at LBNL composite shop. – Stripixel ladders • Staves; thermal analysis completed, preliminary design of stave complete, detailed drawings available June 5 th. Walter Sondheim 6/2/2009 3

Outline continued: – Barrel Mounts • Detailed drawings for pixel barrel mounts complete, now in production at LBNL composite shop. Strip barrel mount preliminary design complete. – Space frame • Preliminary design completed, detailed drawings sent to LBNL composite shop. Contract in place for production. Generating production drawings. – Gas enclosure • Preliminary design and drawings complete. – Big Wheel regions • Preliminary design complete, performing heat transfer measurements at HYTEC. – Isolation mounts • Preliminary design complete, detailed drawings available for review, integration with BNL for mounting in IR. Walter Sondheim 6/2/2009 4

HYTEC Deliverables: • Develop detailed designs and analysis of mechanical components for production based on criteria, sensors and electronics developed by the collaboration. • Integrate all elements into a workable 3 D - CAD model, that maintains a physical envelope agreed to with the PHENIX collaboration, a viable assembly scenario and mechanical tolerances that meet the physics criteria of the detector. Walter Sondheim 6/2/2009 5

Pixel mechanics: Released for production drawing of pixel stave 2 -17 -2009 Walter Sondheim 6/2/2009 6

Pixel mechanics: • Work in collaboration with production vendor, the composite shop at LBNL, managed by Eric Anderssen and Tom Johnson. Agreement reached on material and layup; – – – M 55 J unidirectional carbon, 65. microns thick Thermal plane, 6 X 65 = 390. microns thick Omega cooling channel, 8 X 65 = 520. microns Flatness of thermal plane 100. microns End mounting blocks – unfilled PEEK, precision pins locate stave/ladder to barrel mount – Ground wire at each end attached to stave’s carbon with conductive epoxy. Walter Sondheim 6/2/2009 7

Pixel mechanics; Assembled staves, with travelers in QA process, LBNL composite shop Walter Sondheim 6/2/2009 8

Pixel mechanics; • QA tests for assembled stave: – CMM measurements of thermal plane and stave – Pressure test at 140 psi for 1 minute – Thermal cycle bonded assembly, +20 to -40 C – Leak test to 0. 01 ml-mbar/sec Production will be completed by the end of June Walter Sondheim 6/2/2009 9

PIXEL mechanics; Pixel Layer 1 Pixel Layer 2 Each pixel layer is CAD modeled in as much detail as is available to account for all materials used to maximize the limited space available. This is why detailed effort was made to route the readout cables from each ladder to their SPIRO read-out card. Three different pre-bent extension cables have been designed to interface between the pixel ladder bus cable and the SPIRO boards. Walter Sondheim 6/2/2009 10

Pixel mechanics; Extension cable for the layer 1 ladders, note details of bends, 2 different length cables needed for layer 2 ladders. R 9. 5 40. 0 degrees Walter Sondheim 6/2/2009 11

Stripixel mechanics; • Develop a design for the stave that meets the requirement of keeping the sensor at 0 degrees C, to avoid increase in leakage current from beam irradiation. • Decide to base design on proven ATLAS technology, embedding an Aluminum cooling tube in a carbon skin sandwich, with a carbon foam core. M 55 J skin, . 25 mm thick 1/8 x ¼ in Al. tube Carbon foam core, 4. 5 mm thick PEEK end blocks Walter Sondheim 6/2/2009 12

Stripixel mechanics; • Once ladder electronics demonstrated, BNL designed a prototype Aluminum stave , incorporating all electronic components, fasteners, interconnection materials and cooling. • This design was handed off to HYTEC to perform a thermal analysis and incorporate into the VTX global model – producing detailed drawings. Front Back Walter Sondheim 6/2/2009 BNL 3 D model and drawing 13

Stripixel ladder Thermal model Coolant Flow Calculations Cooling Tube Dimensions Width 0. 00600 Height 0. 00300 Fluid Flow Coefficients Re 10000 Pr 9. 43 m m Total Length 0. 375 m Nu (Sleicher and Rouse) 94. 31 Active Length 0. 75000 m Nu (Petukhov) 96. 81 Active Thermal Area 0. 00450 m 2 cf (Petukhov; f=4 cf) 7. 86 E-03 Number of Ladders/Cooling Loop 12 f (friction coefficient) 0. 031 Total input power 21. 6 W Dh (hydralic diameter) 4. 00 E-03 Heat flux through cooling tube contact 4800 W/m 2 m Thermal Conditions Temperature Drop (tube to bulk fluid) 2. 71 °C Bulk Temperature Increase/ladder 0. 68 °C Bulk Temperature Increase/cooling loop 8. 14 °C r Novec HFE 7200 1420 kg/m 3 n 0. 58 centi. Poise Mean Flow Velocity 1. 02 m/s n 5. 80 E-04 Pa. s Volumetric Flow Rate 1. 84 E-05 m 3/s m Cp k 4. 08 E-07 1220 0. 075 m 2/s J/kg°C W/m. K Mass Flow Rate Dp (total/ladder) Dp (total/cooling loop) 26. 10 0. 51 6. 13 g/s Psi Coolant Properties Walter Sondheim 6/2/2009 Coolant Flow Conditions 14

FEA Results – Expected Temperature Distribution • • Coolant wall temperature of -6° C Peak temperature 3. 2 ºC Meets Strip requirements Sensor temperature ≈-0. 5 ºC Temperature rise between coolant and stave surface 2. 46 ºC • Temperature rise between stave and sensor 3. 09 ºC Cross Section Temperature Surface Temperature Walter Sondheim 6/2/2009 15

FEA Results – Thermal Distortion • • Used nodal temperatures derived from the expected temperature distribution Bending due to CTE difference between pp ROC layup and stave material Peak sensor deflection – 26 µm Some “droop” of ROC due to low sensor CTE No significant thermal distortion Thermal study completed Walter Sondheim 6/2/2009 16

Stripixel mechanics; updated stave design based on BNL model 394. 66 mm layer 4 330. 96 mm layer 3 34. 94 mm stave width *LBNL composite shop has already laid up sheets of M 55 J material that. 408 mm, is. 408 mm thick. change 5 - This material will now be used for 28 -09* the skins of the strip stave. Final detained Drawings will be completed by June 5 th Walter Sondheim 6/2/2009 17

Stripixel mechanics; Alternate ladder stagger between layers 3 & 4, enable use of same ladder electronics in both layers. Ready to submit drawings to LBNL to produce prototype stave during the month of June. Walter Sondheim 6/2/2009 18

Barrel mounts; • Barrel mounts for pixel layers 1 & 2 are complete and detailed drawings have been sent to LBNL to begin production. Tooling is being developed. There are 14 detailed sheets. Walter Sondheim 6/2/2009 19

Barrel Mounts & LBNL; • Pixel layer 1 barrel mount tooling fixture shown on the left. • Pixel layer 2 barrel mount, on the right, in LBNL assembly fixture. Orange blocks are Carbon loaded PEEK material, panel is M 55 J face sheets with Allcomp K 3 type material core. Walter Sondheim 6/2/2009 20

Barrel Mounts & LBNL; • Pixel layer 2 barrel mount in LBNL assembly fixture. Orange blocks are Carbon loaded PEEK material, panel is M 55 J face sheets with Allcomp K 3 type material core. Walter Sondheim 6/2/2009 21

VTX Support Structure; Space Frame Barrel mounts Space frame detailed drawings sent to LBNL. Contract in place to begin production. Status; waiting on production drawings which will be available in June. Walter Sondheim 6/2/2009 22

Space Frame & Gas Enclosure; • The Space frame will be constructed using CN 60/EX 1515 Carbon cloth material, thicker then M 55 J, less labor intensive which reflects on the cost. – Detail production drawing set needs final adjustment based on updated length of strip-pixel ladder. Material is in hand at LBNL, because contract has been in place. • The Gas Enclosure is made from thin sheets of G 10 type material, gas seals soft Silicone and Mylar tape as needed. – Detail drawings generated, including allowance for mounting and services penetrations. Walter Sondheim 6/2/2009 23

Big Wheel Region; • “Big wheel region” are where read-out electronic cards for the VTX barrel layers, as well as the FVTX read-out cards – 5 layers at each end of the barrel; – 1 layer for strip-pixels, 3 layers for pixels and 1 layer for FVTX. • Fabricated a full scale Big Wheel cooling plate, incorporating a 3/16” diameter Aluminum tube bonded along the edge using Tra-Con 2902 silver loaded epoxy. • To mock up the expected 30 watt head load from the SPIRO III board or 230 watts from each FVTX disk, we are using Watlow pressure sensitive heater pads. • To duplicate thermal interface between the SPIRO board and the cooling plate we are using Beroquist Gap-Pad 500 S 35 pads. Walter Sondheim 6/2/2009 24

Big Wheel bench test; Walter Sondheim 6/2/2009 25

Isolation Mounts and Mounting in the IR: The three isolation mounts, or flexures, are based on a proven HYTEC design for a space launched telescope called “stereo” Solar Terrestrial Relations Observatory. • Interface designed between VTX assembly and existing mounts for the HBD detector, currently in the IR, supported between the Central Magnet pole pieces. Robert Pak will have details in his talk. Walter Sondheim 6/2/2009 26

Summary; • Pixel stave; – In production at LBNL, total 30 minimum + spares, completed in June 09. 20 staves are in the queue at LBNL for CMM work. • Stripixel staves; – Preliminary engineering and design complete, detailed drawings complete this week, send to LBNL June 09. LBNL will work on producing a prototype stave during the month of June. • Barrel Mounts; – Pixel barrel mounts in production at LBNL. – Stripixel barrel mounts, update complete. • Space Frame; – Design complete, update detailed drawings by beginning of June 09, available for review. Contract in place with LBNL. Walter Sondheim 6/2/2009 27

Summary cont; • Gas Enclosure; – Preliminary design completed, available for review. • Big Wheel Region; – Preliminary design work completed, continue thermal studies at HYTEC, generate detailed drawings July 09. • Isolation Mounts; – Detailed drawings available in June 09. Walter Sondheim 6/2/2009 28