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DOE issues RFQ for clean-energy projects at WIPP
The Department of Energy has issued a request for qualifications (RFQ) for interested parties that are looking to establish carbon pollution–free electricity (CFE) projects at its Waste Isolation Pilot Plant site in New Mexico.
G. C. Pomraning
Nuclear Science and Engineering | Volume 136 | Number 1 | September 2000 | Pages 1-14
Technical Paper | doi.org/10.13182/NSE00-A2144
Articles are hosted by Taylor and Francis Online.
We consider the energy-dependent pencil beam problem for a thin slab with screened Rutherford scattering. Under certain approximations, this problem can be reduced to a monoenergetic problem with an effective depth-dependent scattering cross section [overbar]s(z). The z dependence of this cross section arises from the explicit z dependence of the true scattering cross section s(z,E), as well as from an induced z dependence associated with the energy dependence of s(z,E). Prior work led to a quadrature result for the scalar flux in the special case that [overbar]s is a constant, independent of z. In this paper, we generalize this result by allowing [overbar]s(z) to have an arbitrary z dependence. We use these considerations to show that simple homogenization, namely, replacing [overbar]s(z) by its average over the slab, can lead to significant errors in the scalar flux. A more detailed homogenization algorithm is suggested, involving an effective screening parameter in the screened Rutherford scattering phase function, as well as an effective depth coordinate z.