Volume 1 Issue 1

Authors: Yang Liu; Wenqiang Meng; Zheng’e Wang; Bingqian Wei

Abstract: Horseshoe cross-section and circular cross-section are commonly used in water diversion project and water delivery project. It is difficult to calculate hydraulic elements of nonstandard horseshoe shape and circular shape because of their complex section. This article gives the formulas of hydraulic elements and iterative formulas of normal depths and critical depths of horseshoe shape section composed of 6 arcs and 2 kinds of irregular circular shape section by mathematical derivation. And on the basis of the relation with depth, normal depth and critical depth, we can estimate the type of water surface profile. It can be applied in calculation of water surface profile in 81.68 km Qinling tunnel of south water to north project. The formulas of normal depth and critical depth and hydraulic elements can be expected to be used in other similar water delivery project.

Keywords: Hydraulic elements; Normal depth; Critical depth; Water surface profile


Authors: Murali. K; Noarayanan. L; Sundar. V

Abstract: The wave run-up over beaches and coastal structures is the most important parameter that dictates the fixing of the crest elevation in order to avoid flooding during extreme events, like tsunami, typhoon and storm surge. The choice of type depends on the purpose for which it is proposed. This paper deals with the study of efficiency of vegetation as a buffer system in attenuating the incident ocean waves through a well-controlled experimental program. The focus of this study was on the measurement of forces due to Cnoidal waves on a model building mounted on a slope in the presence of varying densities of vegetation, starting with no vegetation present. In order to obtain a holistic view of the wave-vegetation interaction problem chosen for study, the vegetative parameters like the width of the green belt, its position from the reference line, diameter of the individual stems, and the spacing between them and their rigidity were varied. This paper introduces two new parameters, namely, Vegetation-Flow Parameter that combines the characteristics of vegetation and waves and Vegetal Parameter that describes the width of green belt (BG), spacing (SP) and diameter (D) of the vegetation. The details of experimental test set-up, measurement procedures, and results on the effect of vegetation on the variation of forces on a model building are presented and discussed in this paper.

Keywords: Cnoidal Waves; Vegetal Stems; Wave Force; Vegetal Drag; Vegetation Flow Parameter; Staggered Vegetation; Vegetal Parameter


Authors: Harry Edmar Schulz; Luiz Antonio Daniel; Marcio Ricardo Salla

Abstract: Experiments on Chemical Oxygen Demand (COD) performed in an ozonization column for wastewater treatment showed fluctuations following irregular time patterns, which could not be explained only by the experimental uncertainties or by stripping, the last being the cause of fluctuations during the first stages of ozonization procedures. Fluctuations observed in more advanced times of the experiments suggest that changes in the oxidation state of the organic matter also affected the COD values. The effect of intermediate compounds was considered in order to quantify this influence. A mathematical model is proposed in this study, which considers the consequences of intermediate compounds formed during oxidation. The different behaviors observed in the COD results of the ozonization column could be explained applying the model with different sets of adjustable constants. The joint analysis of the experimental results and the mathematical model allows suggesting that fluctuations observed in COD results, superposed to the mean decreasing trend and occurring at larger contact times, are forced by organic intermediate compounds.

Keywords: Wastewater Treatment; Water Conservancy; Ozone; Ozonization Columns; COD Fluctuations