lbnf horns update - indico-fnal (indico)€¦ · – plate frame, pinned & bolted. – select...

Long-Baseline Neutrino FacilityLBNF

LBNF Horns Update

Cory Crowley

BIWG

December 05, 2019

LBNF

Outline

12.05.19 Cory Crowley | LBNF Horns Update2

• Horn A Design Status

• Horn Design Considerations for B & C

• Module Design Status

• Upcoming Work

LBNF

Horn Design – Horn A FEA

3

• Inner & Outer Conductors Analyzed Last Year

– Acceptable max temperatures of 65C & min S.F. of 2.2

w/6061-T6. Increase to 2.8 w/6013-T6 due to fatigue life

increase (124MPa vs. 97MPa).

– Should take advantage of better materials on inner

conductor & high-stress stripline regions.

• Stripline

– Analyzed for temperature & stress concerns, basic modal

analysis. Must be experimentally tested & verified.

FEA Credit: Zhijing Tang / Ang Lee

12.05.19 Cory Crowley | LBNF Horns Update

LBNF

Revision in Progress

4 12.05.19 Cory Crowley | LBNF Horns Update

Make this 400mm?

• Requested change per RAL integration meeting 12/4/19.

• John Back is currently analyzing & this will likely be a reality by next

week.

LBNF

Still Gauging Impact of Updates

5

• Most significant update is different target design.

– Shorter target length (~150cm) & no D.S. target mount needed.

– Cone transition on U.S. end (which horn A must mimic) to reduce deflection.

• Should reduce horn EDEP further on D.S. end where most problematic.

• Stress / erosion concerns arose after NuMI Horn prototype disassembly.

– Found that wear resistant nickel coating wore through in several areas.

• Horn A inner conductor changed from 2mm thick to 2.5mm thick to allow

more material for stress distribution / reduced joule heating / Safety

Factor.

• Endcap had to be stiffened throughout analysis iterations due to high

magnetic stresses from 300kA pulse.

• Thicker wall also helps keep circularity requirements due to 30cm

diameter cone on U.S. end & keep conservative design with unknown

erosion effects, 300kA pulse, variability in cooling, etc…

• Still need to document heat input into horn A I.C. from hot target tube.


LBNF

Horn Design – Current Design Status (Horn A)


LBNF

Horn A Design Prototypes – Water Ports

8

• LBNF Horns pursue a revision of port design as

compared to NuMI / BNB. Different from T2K as well.

• Small footprint, inexpensive, immediate assembly,

higher pressure rating, & reduced component count.

• Required prototype testing in preparation for design

review & to verify resilience of concept.


LBNF

Horn A Design Prototype – Conductor Supports

9

• Conductor supported by 3 rods in tension as opposed to compression.

• Tension method required for larger horns due to L^2 term in critical

buckling denominator. ~1.5m diameter horns would need large

spacers if using available designs.

• Desire to make a resilient, minimal mass, universal conductor support.


LBNF

Horn A Design Prototype – Conductor Supports

10

• Prototype / Design Advancement

– Full thermal, stress / cyclic fatigue, & water flow analysis.

– Built mockup for technician assembly training / design

review aid.

– Electrical analysis remains for ~800V.

Print Credit:Quinn P.

FEA Credit: Ang Lee& Jacob Kintner


LBNF

Horn Design – Considerations for Horns B & C

11

Max V@PS

Max Allow. E Field

Max Isolator PathLength Potential

Horn AΔV

Horn BΔV

Horn CΔV

~3700V 35V/.001” 5V/.001” ~550V ~1550V ~1050V

EE Credit: Ken Quinn


LBNF

Horn Design – Horns B & C FEA

12

• Inner & Outer Conductors

– Very resilient designs utilizing 6061-T6. Max conductor temp 28C, need to

incorporate equalization sections (80C) into actively cooled conductor volume.

• Stripline

– Analyzed temperature &

stress, basic modal analysis.

Must also be experimentally

tested & verified. B & C

design should be a mirror.

FEA Credit: Zhijing Tang / Ang Lee


LBNF

Design Plan


• Would like to confirm:

– Outer conductor diameter is large enough that incorporation of

equalization sections has no impact.

– Flaring of I.C. to reach O.C. outside of advertised focal length has trivial

impact on physics.

• Good models will take a little time, but I could provide dimensions for

flux simulations that would be on par with what Laura used for

optimization effort. Is this of use? Or better to wait?

LBNF

Module Design – Horn Integration

14

• Mainframe Placement

– Endwalls & stripline shielding

block (SLB).

• Challenging SLB Connection

– Increased clamping surface area.

– Increased voltage potential at

Horn C (3.7kV).

– Increased reusability / resilience.


LBNF

Module Design – Horn & Target Integration

15

• Challenges

– SLB Connection

– Utility feedthroughs

– Voltage Issues

– More and more and more…..


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Module Design – Mainframe & Motion Control

16

• Construction

– Plate frame, pinned & bolted.

– Select areas of stainless steel where required.

– Allows for ¾” gap to all shield blocks for remote

alignment of horn.

– Designed for life of facility.

• Motion Control Concept

– Simple sliding block & pad joints for horizontal

translation.

– Vertical actuation internal to module mainframe.

Design Credit: Mike Campbell


LBNF

Major Push: Standardization of Ancillary Structures

17

• Everything needs to have identical distance to beam centerline.

– Stripline block pads.

– Carriage Support Beams.

– Stripline Connection Point to Horns.


LBNF

Working Towards Improving Cartoons

18

• Engineering placeholders need to be improved.

– Conductor Profiles

– Stripline Design

– Water tanks

– Connections to Modules


Design Credit: Mike Campbell

LBNF

Summary

19

• Horn & Support Structure design progressing according to plan.

• Roughly 1 year remaining on final design of Horn A, followed by

fabrication start of conductors & stripline components.

• Anticipating additional prototyping:

- Critical stripline ceramics (~1000+).

- Horn A + Stripline.

- Horn B & C Stripline.

• Need to advance Horn B & C conductor design to help advance

target chase / modules / simulations...

• Likely going to re-analyze Horn A stripline due to design

changes, but Horn A conductor analysis still valid after transition

to cone on U.S. end. Should be judicious with FEA (Time / $$$).

• What should I provide? Horn B & C revised equalization specs?


lbnf horns update - indico-fnal (indico)€¦ · – plate frame, pinned & bolted. – select...

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