Pin Power Distribution Determined by Analyzing the Rotational Gamma Scanning Data of HANARO Fuel Bundle

  • Published : 1998.10.01


The pin power distribution is determined by analyzing the rotational gamma scanning data for 36 element fuel bundle of HANARO. A fission monitor of Nb$^{95}$ is chosen by considering the criteria of the half-life, fission yield, emitting ${\gamma}$-ray energy and probability. The ${\gamma}$-ray spectra were measured in Korea Atomic Energy Research Institute(KAERI) by using a HPGe detector and by rotating the fuel bundle at steps of 10$^{\circ}$. The counting rates of Nb$^{95}$ 766 keV ${\gamma}$-rays are determined by analyzing the full absorption peak in the spectra. A 36$\times$36 response matrix is obtained from calculating the contribution of each rod at every scanning angle by assuming 2-dimensional and parallel beam approximations for the measuring geometry. In terms of the measured counting rates and the calculated response matrix, an inverse problem is set up for the unknown distribution of activity concentrations of pins. To select a suitable solving method, the performances of three direct methods and the iterative least-square method are tested by solving simulation examples. The final solution is obtained by using the iterative least-square method that shows a good stability. The influences of detection error, step size of rotation and the collimator width are discussed on the accuracy of the numerical solution. Hence an improvement in the accuracy of the solution is proposed by reducing the collimator width of the scanning arrangement.



  1. Nucl. Tech. v.57 J.T. Dawson;G. Smith
  2. Nucl. Tech. v.68 G. Ducros
  3. Nature v.217 D.J. de Rosier;A. Klug
  4. IEEE Trans. Nucl. Sci. v.NS-21 Z.H. Cho
  5. Astrophys. J. v.386 J.M. Hollis;J.E. Dorband;F. Yusef-Zadeh
  6. Los Alamos Scientific Laboratory Report, LA-4676 B.K. Barnes;J.R. Phillips
  7. Los Alamos Scientific Laboratory Report, LA-UR-81-1662 B.K. Barnes;J.R. Phillips;M.L. Barnes
  8. Int. J. Ener. Res. v.20 C. Niculae;T. Craciunescu;R. Dobrin
  9. Nucl. Instr. and Meth. v.A312 D.F.G. Reher;B. Denecke
  10. Nucl. Sci. and Eng. v.118 R.J. Estep;T.H. Prettyman;G.A. Sheppard
  11. private communications B.J. Jun
  12. Atomic Energy of Canada Limited Report, AECL-5236 J.D. Chen;D.G. Boase;R.B. Lypka
  13. HANARO Safety Analysis Report, KAERI/TR-710/96 v.2 Korea Atomic Energy Research Institute
  14. Table of Isotopes R.B. Firestone;V.S. Shirley;C.M. Baglin;S.Y.F. Chu;J. Zipkin
  15. NUDAT Wallet wide format from NNDC, Feb 96.
  16. Nucl. Instr. and Meth. v.137 G.W. Phillips;K.W. Marlow
  17. Nucl. Instr. and Mech. v.144 S. Taczanowski
  18. NISTIR 5632 J.H. Hubbell;S.M. Seltzer
  19. Complete Report for HANARO Work, KAERI/PR-001/97 Korea Atomic Energy Research Institute
  20. IEEE Trans. Nucl. Sci. v.44 T. Yuasa;M. Akiba;T. Takeda;M. Kazama;A. Hoshino;Y. Watanabe;K. Hyodo;F.A. Dilmanian;T. Akasuka;Y. Itai
  21. IEEE Trans. Nucl. Sci. v.44 G.L. Zeng;G.T. Gullberg
  22. J. Roy. Stat. Soc. v.39 A.P. Dempster;N.M. Laird;D.B. Rubin
  23. Phys. Rev. v.106 E.T. Jaynes
  24. Numerical Methods for Least Square Problems Å. Bjorck
  25. IEEE Trans. Nucl. Sci. v.NS-21 T.F. Budinger;G.T. Gullberg
  26. Nucl. Instr. and Meth. v.101 M. Goitein
  27. J. Korean Nucl. Soc. v.24 Y.-G. Lee;S.-H. Eom;K.-J. Park;K.-P. Hong;S.-G. Ro