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[Licence| Download | New Version Template] adst_v3_0.tar.gz(2413 Kbytes)
Manuscript Title: Code OK3 - An upgraded version of OK2 with beam wobbling function
Authors: A.I. Ogoyski, S. Kawata, P.H. Popov
Program title: OK3
Catalogue identifier: ADST_v3_0
Distribution format: tar.gz
Journal reference: Comput. Phys. Commun. 181(2010)1332
Programming language: C++.
Computer: PC (Pentium4, 1GHz or more recommended).
Operating system: Windows or UNIX.
RAM: 2048 MBytes
Keywords: Ion beam, Inertial confinement fusion, Energy deposition, Fuel pellet.
Classification: 19.7.

Does the new version supersede the previous version?: Yes

Nature of problem:
In heavy ion fusion (HIF), ion cancer therapy, material processing, etc., a precise beam energy deposition is essentially important [1]. Codes OK1 and OK2 have been developed to simulate the heavy ion beam energy deposition in three-dimensional arbitrary shaped targets [2,3]. Wobbling beam illumination is important to smooth the beam energy deposition nonuniformity in HIF, so that a uniform target implosion is realized and a sufficient fusion output energy is released.

Solution method:
OK3 code works on the base of OK1 and OK2 [2,3]. The code simulates a multi-beam illumination on a target with arbitrary shape and structure, including beam wobbling function.

Reasons for new version:
The code OK3 is based on OK2 [3] and uses the same algorithm with some improvements, the most important one is the beam wobbling function.

Summary of revisions:
  1. In the code OK3, beams are subdivided on many bunches. The displacement of each bunch center from the initial beam direction is calculated.
  2. Code OK3 allows the beamlet number to vary from bunch to bunch. That reduces the calculation error especially in case of very complicated mesh structure with big internal holes.
  3. The target temperature rises during the time of energy deposition.
  4. Some procedures are improved to perform faster.
  5. The energy conservation is checked up on each step of calculation process and corrected if necessary.
New procedures included in OK3
  1. Procedure BeamCenterRot() rotates the beam axis around the impinging direction of each beam.
  2. Procedure BeamletRot() rotates the beamlet axes that belong to each beam.
  3. Procedure Rotation() sets the coordinates of rotated beams and beamlets in chamber and pellet systems.
  4. Procedure BeamletOut() calculates the lost energy of ions that have not impinged on the target.
  5. Procedure TargetT() sets the temperature of the target layer of energy deposition during the irradiation process.
  6. Procedure ECL() checks up the energy conservation law at each step of the energy deposition process.
  7. Procedure ECLt() performs the final check up of the energy conservation law at the end of deposition process.
Modified procedures in OK3
  1. Procedure InitBeam(): This procedure initializes the beam radius and coefficients A1, A2, A3, A4 and A5 for Gauss distributed beams [2]. It is enlarged in OK3 and can set beams with radii from 1 to 20 mm.
  2. Procedure kBunch() is modified to allow beamlet number variation from bunch to bunch during the deposition.
  3. Procedure ijkSp() and procedure Hole() are modified to perform faster.
  4. Procedure Espl() and procedure ChechE() are modified to increase the calculation accuracy.
  5. Procedure SD() calculates the total relative root-mean-square (RMS) deviation and the total relative peak-to-valley (PTV) deviation in energy deposition non-uniformity. This procedure is not included in code OK2 because of its limited applications (for spherical targets only). It is taken from code OK1 and modified to perform with code OK3.

Running time:
The execution time depends on the pellet mesh number and the number of beams in the simulated illumination as well as on the beam characteristics (beam radius on the pellet surface, beam subdivision, projectile particle energy and so on). In almost all of the practical running tests performed, the typical running time for one beam deposition is about 30 s on a PC with a CPU of Pentium 4, 2.4 GHz.

References:
[1] A. I. Ogoyski, et al., Heavy Ion beam irradiation non-uniformity in inertial fusion, Phys. Lett. A Vol. 315 (2003) 372-377
[2] A. I. Ogoyski, et al., Code OK1 - Simulation of multi-beam irradiation on a spherical target in heavy ion fusion, Computer Physics Communications 157 (2004) 160-172.
[3] A. I. Ogoyski, et al., Code OK2 - A simulation code of ion-beam illumination on an arbitrary shape and structure target, Computer Physics Communications 161 (2004) 143-150.