Neutronic design study of accelerator driven system (ADS) for Jordan subcritical reactor as a neutron source for nuclear research.
In this paper, a preliminary neutronic design study of an accelerator driven subcritical system for Jordan Subcritical Assembly (JSA) is presented. The conceptual design of coupling the JSA core with proton accelerator and spallation target is investigated, and its feasibility as a neutron source for nuclear research, and possibly for target irradiation and isotope production evaluated. 3D MCNPX model of the JSA reactor, the accelerator beam, and the Pb target was developed, based on actual reactor parameters. MCNPX calculations were carried out to estimate the absolute radial and axial neutron flux in the reactor, and to calculate the multiplication factor Keff and heat generated in the reactor. Numerical results showed an enormous increase in the neutron flux, by seven orders of magnitude, compared to the current JSA core design using Pu-Be source. In this research the results obtained are discussed and compared with those of the JSA, and do confirm the feasibility of utilizing the JSA as a viable nuclear research facility with adequate neutron flux.
Design, Development and Installation of Jordan Subcritical Assembly
Following its announcement in 2007 to pursue a nuclear power program and in the absence of any nuclear facility essential for the education, training, and research, Jordan decided to build a subcritical reactor as its first nuclear facility. Jordan Subcritical Assembly (JSA) is uranium fueled light water moderated and reflected subcritical reactor driven by a plutonium-beryllium source, and the core consists of 313 LEU fuel rods, loaded into a water-filled vessel in a square lattice of 19.11 mm pitch. The fuel rods are based on PWR fuel structural pattern type, made of uranium oxide (UO2) with 3.4 wt% 235U enrichment in zirconium alloy (Zr-4) cladding. Design, optimization, and verification were performed using MCNP5 nuclear code; the computed effective multiplication factor is 0.95923. The JSA is designed to fulfill the training needs of students and is equipped to perform all of the fundamental experiments required for a typical nuclear engineering university program. This paper presents the design, development, modeling, core analysis, and utilization of Jordan’s first nuclear facility and why this simplified low cost reactor presents an attractive choice to fulfill the preliminary experimental needs of nuclear engineering education in developing countries.
Yet another application of the Gauss-Bonnet Theorem for the sphere
where K and dAg denote the Gaussian curvature and the area element of g, respectively. In particular, this implies the existence of at least an elliptic point of (S, g). In this short note we prove the Fundamental Theorem of Algebra as a consequence of this fact. As far as the authors know, this proof is new. Moreover, it does have the advantage of being directly based on the work of Gauss, who was the first mathematician giving an universally accepted proof of the Fundamental Theorem of Algebra (see [2], [3]). Hence our argument can also have some historical and pedagogical interest. As it is well known, the stereographic projection allows to identify the sphere S with the one-point compactification Ĉ = C ∪ {∞} of the complex plane C. Let us take p(z) = a0 + a1z+ · · ·+ anz n with a0 an 6= 0 and let us assume that p(z) 6= 0 for all z ∈ C. We set p∗(z) = an + an−1z + · · ·a0z , that is, the i-th coefficient of p∗(z) is the (n− i)-th coefficient of p(z). Clearly, p∗(z) = z n p(1/z) for all z ∈ C \ {0}. Put