Measuring the Flow Functions of Pharmaceutical Powders Using the Brookfield Powder Flow Tester and Freeman FT4

This study examined the feasibility of combining data from different powder flow testers to determine the flow function characteristics of pharmaceutical powders. The Brookfield PFT and Freeman FT4 can measure flow function over different scales of consolidation load but were found to be most complementary with CRM limestone powder and lactose. The brittle behaviour of Easytab particles at higher loads made obtaining repeatable results with the FT4 challenging. By using the method of Wang et al., where the flow function coefficient ffc is plotted against the dimensionless cohesion C* (measured cohesion Ta divided by the initial compaction I), a plot was formed which could be used to predict the behaviour of other systems, which compared well with previous studies.

Development of a Novel Plastic Hardening Model Based on Random Tree Growth Method

The flow functions for plastic deformation have been developed to describe the plastic behavior of sheet metals. In order to explain the plastic behavior of material in metal forming processes via finite element analyses, two basic input functions should be applied. One is the yield function that determines the yielding behavior. The other is flow function to describe the hardening property of sheet metal. To describe the hardening properties of sheet materials under quasi-static tension condition in a wide range of plastic straining, various different equations are known such as classical Swift, Voce, Holloman, combined Swift-Voce, and recently proposed Kim-Tuan equations, etc. Those hardening equations are based on metallurgical or phenomenological investigations, and however the application of each equation has some limitation. In this study, the random growth of the binary tree method is introduced to develop the reliable hardening equations of various sheet metals (i.e. DP980, Pure Ti, AA5052-O, STS304, Ti-Gr2, and Mg-AZ31B) with no knowledge of existing hardening equation types. To evaluate the proposed method, the proposed equations developed by new approach are compared with the Voce, Swift, and Kim-Tuan hardening equations for stress-strain curve and the plastic instability point. Consequently, the proposed approach was proven to be very efficient to find the reliable and accurate hardening equation for any kind of materials.

Optimal and Perfectly Parallel Algorithms for On-demand Data-Flow Analysis

Interprocedural data-flow analyses form an expressive and useful paradigm of numerous static analysis applications, such as live variables analysis, alias analysis and null pointers analysis. The most widely-used framework for interprocedural data-flow analysis is IFDS, which encompasses distributive data-flow functions over a finite domain. On-demand data-flow analyses restrict the focus of the analysis on specific program locations and data facts. This setting provides a natural split between (i) an offline (or preprocessing) phase, where the program is partially analyzed and analysis summaries are created, and (ii) an online (or query) phase, where analysis queries arrive on demand and the summaries are used to speed up answering queries.In this work, we consider on-demand IFDS analyses where the queries concern program locations of the same procedure (aka same-context queries). We exploit the fact that flow graphs of programs have low treewidth to develop faster algorithms that are space and time optimal for many common data-flow analyses, in both the preprocessing and the query phase. We also use treewidth to develop query solutions that are embarrassingly parallelizable, i.e. the total work for answering each query is split to a number of threads such that each thread performs only a constant amount of work. Finally, we implement a static analyzer based on our algorithms, and perform a series of on-demand analysis experiments on standard benchmarks. Our experimental results show a drastic speed-up of the queries after only a lightweight preprocessing phase, which significantly outperforms existing techniques.

About the features of hypersonic flow past a yawed plate

The flow around the yawed plate in the regime of strong interaction is considered in the case when the pressure at its trailing edge is not constant, but changes along the transverse coordinate. It is shown that in the case of large transverse gradients of the induced pressure, the type of expansions of flow functions in the vicinity of the leading edge changes significantly and the third term of the expansions should be taken into account.

Robust Nonlinear Newton Solver With Adaptive Interface-Localized Trust Regions

Summary The interplay of multiphase-flow effects and pressure/volume/temperature behavior encountered in reservoir simulations often provides strongly coupled nonlinear systems that are challenging to solve numerically. In a sequentially implicit method, many of the essential nonlinearities are associated with the transport equation, and convergence failure for the Newton solver is often caused by steps that pass inflection points and discontinuities in the fractional-flow functions. The industry-standard approach is to heuristically chop timesteps and/or dampen updates suggested by the Newton solver if these exceed a predefined limit. Alternatively, one can use trust regions (TRs) to determine safe updates that stay within regions that have the same curvature for numerical flux. This approach has previously been shown to give unconditional convergence for polymer- and waterflooding problems, also when property curves have kinks or near-discontinuous behavior. Although unconditionally convergent, this method tends to be overly restrictive. Herein, we show how the detection of oscillations in the Newton updates can be used to adaptively switch on and off TRs, resulting in a less-restrictive method better suited for realistic reservoir simulations. We demonstrate the performance of the method for a series of challenging test cases ranging from conceptual 2D setups to realistic (and publicly available) geomodels such as the Norne Field and the recent Olympus model from the Integrated Systems Approach for Petroleum Production (ISAPP) optimization challenge.