The impact of modularisation strategies on small modular reactor cost

Small Modular Reactors (SMRs) based on established light-water technology have gained a lot of attention from the nuclear industry; however, the potential that SMRs have to reduce the cost of nuclear construction has been under-studied. Modularisation is a cost reducing mechanism where a SMR power plant is subdivided into smaller units, or modules. These modules can be produced offsite in a controlled environment, potentially offering cost reductions that offset their apparently higher capital costs. This paper will investigate the effects modularisation and standardisation might have on SMR capital costs. Modularisation and standardisation not only reduce direct and indirect costs, respectively, but also enable activation of other cost-reducing mechanisms, such as shifting construction work from site to a factory, transferring learning between tasks, and achieving economies of multiples. It will show that constructing a SMR using the same methods as current large reactors is not economically feasible and will demonstrate how modularisation reduces SMR capital costs. The primary constraints on module size are imposed by weight and height transport limitations, linking reactor size to ease of modularisation. This leads to an analysis of which SMR components and structures should be targeted for modularisation in order to achieve optimal cost benefits

Numerical Simulations of Melt-Driven Double-Diffusive Fluxes in a Turbulent Boundary Layer beneath an Ice Shelf

AbstractThe transport of heat and salt through turbulent ice shelf–ocean boundary layers is a large source of uncertainty within ocean models of ice shelf cavities. This study uses small-scale, high-resolution, 3D numerical simulations to model an idealized boundary layer beneath a melting ice shelf to investigate the influence of ambient turbulence on double-diffusive convection (i.e., convection driven by the difference in diffusivities between salinity and temperature). Isotropic turbulence is forced throughout the simulations and the temperature and salinity are initialized with homogeneous values similar to observations. The initial temperature and the strength of forced turbulence are varied as controlling parameters within an oceanographically relevant parameter space. Two contrasting regimes are identified. In one regime double-diffusive convection dominates, and in the other convection is inhibited by the forced turbulence. The convective regime occurs for high temperatures and low turbulence levels, where it is long lived and affects the flow, melt rate, and melt pattern. A criterion for identifying convection in terms of the temperature and salinity profiles, and the turbulent dissipation rate, is proposed. This criterion may be applied to observations and theoretical models to quantify the effect of double-diffusive convection on ice shelf melt rates.</jats:p

Towards automated tracking of initiation and propagation of cracks in aluminium alloy coupons using thermoelastic stress analysis

Raw Thermoelastic Stress Analysis (TSA) data to accompany submitted paper. Data collected during constant amplitude tensile-tensile cyclic loading. Manuscript submitted to Journal of Nondestructive Evaluation (Springer). Submission Date June 2018

Comparing full-field data from structural components with complicated geometries

A new decomposition algorithm based on QR factorization is introduced for processing and comparing irregularly shaped stress and deformation datasets found in structural analysis. The algorithm improves the comparison of two-dimensional data fields from the surface of components where data is missing from the field of view due to obstructed measurement systems or component geometry that results in areas where no data is present. The technique enables the comparison of these irregularly shaped datasets without the need for interpolation or warping of the data necessary in some other decomposition techniques, for example, Chebyshev or Zernike decomposition. This ensures comparisons are only made between the available data in each dataset and thus similarity metrics are not biased by missing data. The decomposition and comparison technique has been applied during an impact experiment, a modal analysis, and a fatigue study, with the stress and displacement data obtained from finite-element analysis, digital image correlation and thermoelastic stress analysis. The results demonstrate that the technique can be used to process data from a range of sources and suggests the technique has the potential for use in a wide variety of applications