Target & Horns Fluxes were distributed. W/ J-PARC type 2.5 o, 2 o, 3 o. Target cooling evaluation and test Target stress analysis Serious stress analysis started for 1 st horn consistent w/ simple calculation Optimization of the horns Load test was done w/ mini-1 st horn.

Fluxes w/ J-PARC type 2.5 o, 2 o, 3 o.

Progress by S.Ueda and Target&Monitor group Required heat convection coefficient btw. water and graphite was evaluated. T surf < 100 o Both  T surf and T water were evaluated. Actual heat convection coefficient was measured. Target cooling Q : ~60kJ/3.3sec. T water T surf water target Q

T surf Max. α=6α=6  T surf Required Heat Convection coefficient Q Z=0cm Z=90cm beam ターゲット 水 Result >6.5[kW/Km 2 >5.8[kW/Km 2 Heat deposit onto the water is not yet taken account. These are based on simple calculations. FEM analysis is being carried out. S.Ueda

horn target 90 cm One of cooling schems

electrode Cooling water Cooling Test water DC Current

Thermal stress estimation (ANSYS) Condition: Simulate the hottest part (z=100mm ~ 200mm) : The edges (z=100 & 200mm) are fixed in z direction. just after the spill (after 5  s) Equivalent stress (Because both of the edges were fixed) z (mm) maximum r=0, z=200mm maximum temperature ~8.8MPa. (r=0,z~170mm) r (mm) 0 15 slightly larger but consistent with the analytical calculations (analytical calc.: 6.0MPa) (due to the approximation of the temperature distribution) Hayato, Minakawa

Further optimization –Horn1- Parameters default Current I320kA Inner conductor radius r in 26 mm Horn1 Length L1 1.5 m Distance to Horn2 D2 0.5 m Horn2 shape parameter a Horn3 shape parameter a Fixed Parameters Horn2 Length L2 2 m Horn3 Length L3 2.5 m Total Length 11.5 m L1 D2 L2 D3 L3

Rin = 28 mm L1 = 140cm D2 = 50cm

Heat load by radiation to 1 st horn Ver4.8 Rin=23mm, Total : 70kJ/pulse 26mm, Total : 37kJ/pulse 28mm, Total : 35kJ/pulse

Time evolution of temperature at inner-condcutor r in =26mm, L1=150cm, w pulse =0.4ms 最高温度部 Asuming  from K2K (Yamanoi et al.)

Stress analysis using ANSYS beam 1 st horn Cylindrical model Only stress from Lorenz force is considered. Stress from heat load should be considered. 3mm thick aluminum  eq < 20 MPa Deformation < 60  m

I=320kA 3mm thick aluminum  eq < 20 MPa Deformation < 60  m Only stress from Lorenz force  eq < 23 MPa Deformation < 100  m Previous version Rin=26mm Rin=28mm

Load Test FSW w/ Yamanoi