1,721,393 research outputs found
Dataset in support of the article "Towards a genuinely stable boundary closure for pentadiagonal compact finite difference schemes"
No full textDataset supporting the plots in the article:
Wu, L. and Kim, J.W. (2024) Towards a genuinely stable boundary closure for pentadiagonal compact finite difference schemes. Journal of Computational Physics, 10.1016/j.jcp.2024.112887
This dataset contains the ASCII data files and the Tecplot data and layout files that were ORIGINALLY produced in the work and used for generating the figures in the publication. The titles of the files are self-explanatory.
Additional related data collected that was not included in the current data package:
Note that data taken from external sources and used for plotting in Fig. 14c, Fig. 15, and Fig. 17 in the publication is not included. If needed, they should be found from their original source – see reference [17] cited in the paper.
Related projects: EPSRC UK Turbulence Consortium (EP/R029326/1)
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Fan buzz-saw noise under intake flow distortion: a computational study
No full textSteady intake flow distortion due to non-axisymmetric intake geometry and angle of attack of the flight stream can affect various fan tone noise, especially fan buzz-saw noise. In this paper, unsteady CFD simulations have been performed on fully coupled fan and intake models to study the effect of intake flow distortion on fan buzz-saw noise. Three cases have been investigated, namely a baseline case, an axisymmetric distorted case, and a drooped distorted case, and comparisons have been made on the intake noise data extracted from the CFD calculations. The distortion fields generated in the last two cases have been compared and characterised by Fourier-Bessel harmonics. The results show that the distortion generated in the drooped case is more significant and has resulted in stronger circumferential mode scattering appearing initially in the fan domain. The main effect of the distortions in both cases is to cause scattering of the rotor-locked modes into adjacent circumferential harmonics, as the shock waves propagate through the intake ducts.</p
Towards a genuinely stable boundary closure for pentadiagonal compact finite difference schemes
No full textA new optimisation strategy to develop high-order and genuinely stable boundary closure schemes for a pentadiagonal, seven-point stencil, compact finite difference system is proposed. Previous approaches to developing boundary compact schemes often yielded either potential instabilities or non-optimal accuracy in the numerical solutions. In the present optimisation, the numerical accuracy and stability of the compact differencing system are addressed simultaneously by maximising the global accuracy of the system under stability constraints that are enhanced by a non-Dirichlet boundary condition. A unified extrapolation method is proposed to assist in the derivation of boundary schemes. A set of optimised boundary compact schemes is obtained for use along with an existing interior compact scheme. The resultant fourth-order compact finite difference system is applied to flow and acoustic benchmark problems as well as a large-eddy simulation, demonstrating superior performance in numerical stability, accuracy, and spatial resolution
Annual average rainfall and runoff at Wu Long Station.
No full textAnnual average rainfall and runoff at Wu Long Station.</p
Annual sediment discharge at Wu Long Station (1960–2016).
No full textAnnual sediment discharge at Wu Long Station (1960–2016).</p
A new strategy towards stable and accurate boundary closures for high-order finite difference schemes
No full textThis paper presents a generalised strategy to develop linearly stable and accurate boundary closure schemes for large-stencil, high-order, finite difference systems in computational aero acoustics. The optimisation problem is formulated to maximise the global accuracy of the differencing system under a linear stability constraint evaluated by eigenvalue analysis. The strategy for constructing boundary schemes is based on an interpolation-differentiation procedure. Three sets of optimised boundary closure schemes have been presented for three widely used central schemes in computational aero acoustics. The present boundary schemes, when used together with the corresponding central scheme, are guaranteed to be linearly stable. Moreover, they are more accurate compared with the previous boundary schemes optimised for resolution.</p
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Detection results of ApEn on annual sediment discharge at Wu Long station by sliding t.
No full textDetection results of ApEn on annual sediment discharge at Wu Long station by sliding t.</p
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