Modelling Transient Winds

This paper examines the flow field associated with a variety of transient winds and discussed in detail the physical and numerical simulation of a flow structure that could be interpreted as a thunderstorm downburst. The possible pressure field arising from such a structure as it impacts on a high-rise building is examined. Possible differences between such flow phenomena and those corresponding to typical boundary layer winds are observed to occur – the magnitude and importance of these differences currently remains an open point.Laboratorio de Capa Límite y Fluidodinámica AmbientalGrupo Fluidodinámica Computaciona

Modelling Transient Winds

This paper examines the flow field associated with a variety of transient winds and discussed in detail the physical and numerical simulation of a flow structure that could be interpreted as a thunderstorm downburst. The possible pressure field arising from such a structure as it impacts on a high-rise building is examined. Possible differences between such flow phenomena and those corresponding to typical boundary layer winds are observed to occur – the magnitude and importance of these differences currently remains an open point.Laboratorio de Capa Límite y Fluidodinámica AmbientalGrupo Fluidodinámica Computaciona

On the assessment of pedestrian distress in urban winds

Urban winds can cause a risk to pedestrian safety if not properly assessed. High-rise buildings produce a complex flow field at ground level, where regions of accelerated and recirculating flows are present. Gust wind speeds provide an indication of the maximal speed pedestrian might experience due to the unsteady flow. In this study, low- and high-fidelity numerical and experimental techniques to predict pedestrian level winds are tested on a realistic full-scale test-route at the University of Birmingham Campus during a storm event. Results show that it is beneficial to increase the complexity of simulations as a direct correspondence exists between the gust wind speed and the turbulent environment. While not much gain is achieved switching from Irwin Probes to hot-wire anemometry, LES greatly outperforms RANS and challenges experimental simulations in terms of reliability. The validity of the peak factor is also questioned and a general comment on the adequacy of each technique is discussed

Protein fractionation of Hibiscus cannabinus (kenaf) seeds, its characterization, and potential use for water treatment.

This study evaluates the coagulation performance of kenaf protein fractions (KPFs) comprising of albumin (AlbKP), globulin (GloKP), prolamin (ProKP), and glutenin (GluKP), in the treatment of high (500 NTU), medium (150 NTU), and low (30 NTU) turbidity water. Based on preliminary experimental results, the study focused on GloKP due to it outperforming the other kenaf coagulation products (KCPs) in all water types tested. The influence of GloKP, both as a primary coagulant and coagulant aid to aluminum sulfate (AS) on organic matter removal, was examined. Parametric analysis on turbidity, TSS, pH, dosages, retention time, and KPFs storage time was completed. Results indicated that GloKP could be used both as a primary coagulant and coagulant aid. GloKP had a higher turbidity and solids removal than the AlbKP and other KPFs (ProKP and GluKP). Solution pH greatly influenced the performance of the GloKP, and optimum dosage at pH 2 resulted in the highest organic matter removal. High dosages also resulted in negative mobility of particles and a more stable suspension. When used as a coagulant aid to AS, GloKP was more effective in removing dissolved organic carbon (DOC). Scanning electron microscopy elemental analysis (SEM-EDAX) and Fourier transform infrared (FT-IR) spectra showed the structure of the KPFs. SEM-EDAX indicated the presence of metal cations capable of forming complexes essential for flocs formation. The enhanced floc formation, detailed in this paper, is ascribed to the collective effect of charge neutralization of the AS species and the adsorption and bridging effect of the GloKP, which improves the bonds formed between flocs. The coagulation-flocculation process can be significantly improved using dual coagulants. GloKP was also an excellent alternative to its crude (CrKP) and solvent extract (HxKP) form for removing suspended and dissolved particles from all water types. PRACTITIONER POINTS: Kenaf protein fractionates can destabilize stable particles. The globulin protein fractionate (GloKP) aggregated the most particles and contained least dissolved organic material. GloKP is pH sensitive with pH 2 reported as best working pH. Coagulant dosage and coagulation mechanism were assessed