Modelling solids friction factor for dense-phase pneumatic conveying of powders

This paper presents results from an investigation into power-function modelling of solids friction factor for the dilute-phase and fluidised dense-phase (FDP) conveying of powders. Three different diameters/lengths of pipeline were used to generate a wide range of steady-state data and also explore important scale-up issues. The effect of pressure tapping locations on the data and derived models was also investigated. Different sets of power-function model solutions were used for comparison purposes and also to check scale-up stability and accuracy. Comparisons with predictions from recent models developed by other researchers are included. It is concluded that certain forms of the power function model are more stable (in terms of scale-up) than others. The paper also demonstrates how existing models can go unreliable or unstable under certain scale-up conditions and discusses possible causes of such problems

Theoretical Modelling of Rotary Valve Air Leakage for Pneumatic Conveying Systems

Rotary valve air leakage is an important parameter for the design and operation of many dilute- and dense-phase pneumatic conveying systems. Previous methods to estimate air leakage have been largely empirical and have been found inaccurate and/or limited in their use. This paper describes a new theoretical model that has been developed to estimate rotary valve (radial clearance) air leakage. Model predictions are compared with experimental data obtained on a rotating and stationary valve subjected to a wide range of operating pressures typical of dilute- and dense-phase systems. Knowing accurately the air leakage present for any given situation, the required total supplied air mass flow rate can be determined properly for the pneumatic conveying system, so that optimal transport velocities can be established

Evaluation of Belt Conveyor Trajectories

Since the early 1900s, numerical methods have been used to predict the trajectory of material discharged from a belt conveyor. These methods range from the very basic to complex iterative approaches. Some methods predict similar paths and others vary noticeably, however it is clear that they cannot all be correct. The discrete element method (DEM) is also becoming more widely accepted as a design tool, however, hesitation still exists in some quarters stemming from the lack of experimental validation available. A conveyor transfer research facility has been commissioned at the University of Wollongong to experimentally investigate particle flow mechanisms through a variety of conveyor transfers. As part of this research, preliminary investigations into conveyor trajectories have been undertaken at varying belt speeds and material flow rates using granular polyethylene pellets. This paper presents the trajectory results of an experimental test program and compares these findings with numerous numerical trajectory methods as well as DEM simulations in an attempt to validate the predictive approaches available to generate conveyor trajectories. Early findings suggest the method of Booth provided the most accurate prediction, while the DEM also compares favourably to the experimental results

Comparison of Rotary Valve and Blowtank Feed Rate Capacities

Rotary valves and blowtanks are widely used in industry for the pneumatic conveying of products, each having their pros and cons depending on the required application. This paper aims to show the differing results that can be obtained when conveying a product through a common pipeline using either a drop-through rotary valve or a bottom discharge blowtank. The rotary valve system has a number of issues, the main one being air leakage effects, whereas the blowtank system does not as it is an enclosed unit. The results of these experiments showed dramatic differences in product tonnage

Development and Implementation of a Flipped-Classroom Delivery in Engineering Computing and Analysis for First Year Engineering Students

University of Wollongong recently undertook a major restructure of its academic and professional units, after the appointment of a new Vice Chancellor in 2012. As a result, the previous 11 faculties have been merged and rationalised into five new faculties. The Faculty of Engineering and the Faculty of Informatics merged to become the Faculty of Engineering and Information Sciences (EIS), consisting of six schools representing a total of 13 disciplines. Following the restructuring, EIS made the decision to develop a new common first year curriculum for all engineering undergraduate programs, spanning nine disciplines, they being; civil, mining, environmental, electrical, computer, telecommunications, mechanical, materials and mechatronic engineering. The process of developing the new first year subjects was undertaken in 2014 by a Task and Finish (T&F) group aiming for full implementation at the commencement of 2015. Through consultation with key stakeholders from each discipline area, as well as teaching teams from existing first year programs, five new engineering subjects were to be created, to coexist with the unaltered physics and mathematics subjects. The T&F group met regularly over the course of 2014, where they initially tasked with identifying the key mastery skills that all engineering students should have developed by the end of their first year of full time study. These skills were then grouped into themes, leading to the creation of the five new subjects. The final role of the T&F group was to report back to the Heads of School who would then assign key personnel to develop the curriculum content for each new subject. This paper will focus on the development of one of those newly created subjects, ENGG105 Engineering Computing and Analysis, which adopted the flipped-classroom approach to deliver the subject content

Discovery of molecular subtypes in leiomyosarcoma through integrative molecular profiling.

Leiomyosarcoma (LMS) is a soft tissue tumor with a significant degree of morphologic and molecular heterogeneity. We used integrative molecular profiling to discover and characterize molecular subtypes of LMS. Gene expression profiling was performed on 51 LMS samples. Unsupervised clustering showed three reproducible LMS clusters. Array comparative genomic hybridization (aCGH) was performed on 20 LMS samples and showed that the molecular subtypes defined by gene expression showed distinct genomic changes. Tumors from the muscle-enriched cluster showed significantly increased copy number changes (P=0.04). A majority of the muscle-enriched cases showed loss at 16q24, which contains Fanconi anemia, complementation group A, known to have an important role in DNA repair, and loss at 1p36, which contains PRDM16, of which loss promotes muscle differentiation. Immunohistochemistry (IHC) was performed on LMS tissue microarrays (n=377) for five markers with high levels of messenger RNA in the muscle-enriched cluster (ACTG2, CASQ2, SLMAP, CFL2 and MYLK) and showed significantly correlated expression of the five proteins (all pairwise P<0.005). Expression of the five markers was associated with improved disease-specific survival in a multivariate Cox regression analysis (P<0.04). In this analysis that combined gene expression profiling, aCGH and IHC, we characterized distinct molecular LMS subtypes, provided insight into their pathogenesis, and identified prognostic biomarkers

Cognitive and neuroscientific perspectives of healthy ageing

With dementia incidence projected to escalate significantly within the next 25 years, the United Nations declared 2021–2030 the Decade of Healthy Ageing, emphasising cognition as a crucial element. As a leading discipline in cognition and ageing research, psychology is well-equipped to offer insights for translational research, clinical practice, and policy-making. In this comprehensive review, we discuss the current state of knowledge on age-related changes in cognition and psychological health. We discuss cognitive changes during ageing, including (a) heterogeneity in the rate, trajectory, and characteristics of decline experienced by older adults, (b) the role of cognitive reserve in age-related cognitive decline, and (c) the potential for cognitive training to slow this decline. We also examine ageing and cognition through multiple theoretical perspectives. We highlight critical unresolved issues, such as the disparate implications of subjective versus objective measures of cognitive decline and the insufficient evaluation of cognitive training programs. We suggest future research directions, and emphasise interdisciplinary collaboration to create a more comprehensive understanding of the factors that modulate cognitive ageing