Walter Sondheim 6/2/20091 DOE – Review of VTX upgrade detector for PHENIX Mechanics: Walter Sondheim - LANL Mechanical Project Engineer

Walter Sondheim 6/2/20092 VTX global model: “Big Wheel” regions in gas enclosure, where all read out cards are located Space Frame central truss Isolation mounts (3) flexures Pixel layer 1 ladders, followed in R by layer 2 then strip layers 3 &4 View not showing FVTX detector* FVTX detector support cage* Barrel mounts

Walter Sondheim 6/2/20093 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 5th.

Walter Sondheim 6/2/20094 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 6/2/20095 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 3D - 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 6/2/20096 Pixel mechanics: Released for production drawing of pixel stave

Walter Sondheim 6/2/20097 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; –M55J 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 6/2/20098 Pixel mechanics; Assembled staves, with travelers in QA process, LBNL composite shop

Walter Sondheim 6/2/20099 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/ 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/ Pixel mechanics; Extension cable for the layer 1 ladders, note details of bends, 2 different length cables needed for layer 2 ladders degrees R9.5

Walter Sondheim 6/2/ 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. M55J 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/ 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 BNL 3D model and drawing

Walter Sondheim 6/2/ Stripixel ladder Thermal model Coolant Flow Calculations Cooling Tube DimensionsFluid Flow Coefficients Width mRe10000 Height mPr9.43 Total Length0.375mNu (Sleicher and Rouse)94.31 Active Length mNu (Petukhov)96.81 Active Thermal Area m2m2 c f (Petukhov; f=4c f )7.86E-03 Number of Ladders/Cooling Loop12f (friction coefficient)0.031 Total input power21.6WDh (hydralic diameter)4.00E-03m Heat flux through cooling tube contact 4800W/m 2 Thermal Conditions Temperature Drop (tube to bulk fluid)2.71°C Bulk Temperature Increase/ladder0.68°C Bulk Temperature Increase/cooling loop 8.14°C Coolant Properties Novec HFE 7200 r1420kg/m 3 Coolant Flow Conditions n0.58centiPoiseMean Flow Velocity1.02m/s n5.80E-04Pa.sVolumetric Flow Rate1.84E-05m 3 /s m4.08E-07m 2 /sMass Flow Rate26.10g/s CpCp 1220J/kg°C  p (total/ladder) 0.51Psi k0.075W/mK  p (total/cooling loop) 6.13Psi

Walter Sondheim 6/2/ FEA Results – Expected Temperature Distribution Coolant wall temperature of -6° C Peak temperature 3.2 ºC 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 Meets Strip requirements

Walter Sondheim 6/2/ 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/ Stripixel mechanics; updated stave design based on BNL model mm layer mm layer mm stave width.408 mm, change * *LBNL composite shop has already laid up sheets of M55J material that is.408 mm thick. This material will now be used for the skins of the strip stave. Final detained Drawings will be completed by June 5th

Walter Sondheim 6/2/ 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/ 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/ 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 M55J face sheets with Allcomp K3 type material core.

Walter Sondheim 6/2/ Barrel Mounts & LBNL; Pixel layer 2 barrel mount in LBNL assembly fixture. Orange blocks are Carbon loaded PEEK material, panel is M55J face sheets with Allcomp K3 type material core.

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

Walter Sondheim 6/2/ Space Frame & Gas Enclosure; The Space frame will be constructed using CN60/EX1515 Carbon cloth material, thicker then M55J, 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 G10 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/ 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 the thermal interface between the SPIRO board and the cooling plate we are using Beroquist Gap-Pad 500S35 pads.

Walter Sondheim 6/2/ Big Wheel bench test;

Walter Sondheim 6/2/ Isolation Mounts and Mounting in the IR: 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. The three isolation mounts, or flexures, are based on a proven HYTEC design for a space launched telescope called “stereo” Solar Terrestrial Relations Observatory.

Walter Sondheim 6/2/ Summary; Pixel stave; –In production at LBNL, total 30 minimum + spares, completed in June 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/ 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.