FLARE Constructing the detector First FLARE Workshop November 4-6, 2004 Rafael Silva Fermilab / PPD / MD Fermilab Liquid Argon Experiments

Overall Project Scale (Model by Bartoszeck Engineering)

Some numbers Inner tank Inner tank –Height: 108 ft = 33 m –Diameter: 132 ft = 40 m –Volume: 1,500,000 ft 3 = 11,000,000 gal = 42,000 m 3 = 42,000 m 3 Argon density = 1.4  total weight = 60 kton Argon density = 1.4  total weight = 60 kton Weight of inner tank cylindrical wall = 1.5 kton Weight of inner tank cylindrical wall = 1.5 kton

We can divide the design and construction issues in 3 major groups: We can divide the design and construction issues in 3 major groups: Tank Tank Detector Detector Integration of detector into tank structure Integration of detector into tank structure

Tank issues Tank issues Shape Shape Design requirements Design requirements Material Material Insulation Insulation

Shape Shape Double steel wall Double steel wall Insulation between walls Insulation between walls Flat bottom Flat bottom Flat roof (short electronics path) or self-supporting curved roof Flat roof (short electronics path) or self-supporting curved roof

CB&I double steel wall tank

Design requirements Design requirements Roof structure capable of supporting vertical wire load of 300 tons Roof structure capable of supporting vertical wire load of 300 tons Side wall capable of supporting horizontal wire load of 115 tons Side wall capable of supporting horizontal wire load of 115 tons

Design requirements (cont.) Design requirements (cont.) Access to electronics on top of roof Access to electronics on top of roof No leaks (from joints) No leaks (from joints) No contamination (from internal surfaces) No contamination (from internal surfaces)

3D model (Model By Chuck Crimm / FNAL) 3D model (Model By Chuck Crimm / FNAL)

Material Normally used: 9% Ni alloy steel Normally used: 9% Ni alloy steel –3 x costlier than regular carbon steel, –ductile at low temperatures, –somewhat better corrosion resistance. –May it be coated?

Material (cont.) Stainless steel (no atmospheric corrosion) Stainless steel (no atmospheric corrosion) –9 x costlier than regular carbon steel, –ductile at low temperatures, –may have lower strength (thicker, heavier, costlier)

Insulation Insulation Perlite (expanded volcanic glass) Perlite (expanded volcanic glass) –Normal “in place” density range between 8 and 9 lb/ft 3

Detector 6 HV wire sectors, 6 HV wire sectors, 7 cathode planes, and 7 cathode planes, and field shaping tubes in between them. field shaping tubes in between them.

Detector Each wire sector has 6 wire planes oriented at: +30°,-30°,vertical,vertical, -30°, and +30°, in this order.

Layout of wire sectors Layout of wire sectors

Stereo Planes

Field shaping tubes (Model by Bartoszeck Engineering) Field shaping tubes (Model by Bartoszeck Engineering)

How are the wires held in place? Using same method used by Icarus (according to A. Para) Using same method used by Icarus (according to A. Para) –Need to be tested  small scale model One end is connected to the electronics and the other end is connected to the weight One end is connected to the electronics and the other end is connected to the weight

Stereo Wires These are guided through a system of insulated pulleys. These are guided through a system of insulated pulleys. Preliminary estimates indicate availability of space on the sides and at the bottom for the pulleys Preliminary estimates indicate availability of space on the sides and at the bottom for the pulleys Pulleys are staggered and pre-assembled in groups to panels to be located by rails attached to the tank Pulleys are staggered and pre-assembled in groups to panels to be located by rails attached to the tank Prototype required Prototype required

Wire analysis Wire analysis 150  m dia. stainless steel wire 150  m dia. stainless steel wire Max. wire length = 125 ft = 38 m Max. wire length = 125 ft = 38 m Wire tension achieved by 1.3kg weight Wire tension achieved by 1.3kg weight –Max. stereo wire “bowing” (deflection) is 0.38 in = 1 cm –Max. wire elongation = 5.4 in = 14 cm

Integration of detector into tank structure Integration of detector into tank structure Among the options, an analysis was made of the flat roof case Among the options, an analysis was made of the flat roof case –Wire load is supported by space frames (trusses) at the top –Trusses are supported by inner wall –Inner wall also supports horizontal loads from wires

3D model – space frame detail (Model By Chuck Crimm / FNAL)

Example – loading and wall thickness

Example - FEA: hydrostatic load only

Example - FEA: boundary conditions

Example - FEA: static / max. shear

Example - FEA: linear buckling / B.L.F.

Integration of detector into tank structure (cont.) Preliminary analysis indicates feasibility of flat roof and load supported by inner shell Preliminary analysis indicates feasibility of flat roof and load supported by inner shell More loading cases need to be studied More loading cases need to be studied Subsequent more detailed analysis is needed Subsequent more detailed analysis is needed

Fermilab Liquid Argon Experiments