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Whilst numerical modelling is commonly used for simulation to check the design of water conveyance, sluicing and spillway structure design, the numerical modelling has rarely been compared with the physical model tests. The objective of this research presented in this paper was to examine the validity and suitability of the numerical computational fluid dynamics (CFD) modeling method within an ANSYS Fluent/CFD R 18.2 software and compare its results with a fully instrumented and well-run physical model test at the 1:45 scale, carried out for Patrind Hydropower Project located in Pakistan. The physical model test was conducted for confirmation and optimization of a natural de-sanding basin, and diversion of suspended sediment-rich flood waters using a bypass tunnel. The numerical simulation was able to reproduce physical model test results and data gathered over a 7-year project operation to an acceptable level of accuracy. A detailed explanation of the approach used in numerical modelling together with analysis of simulation diagrams of ANSYS Fluent/CFD is also presented. The research shows that a 3D numerical model with accurate boundary conditions and mesh size can replace the need for physical model tests. [ABSTRACT FROM AUTHOR]

A new non-dispersive, anti-washout grout consisting of ordinary Portland cement, slag, superplasticizer, and methylbenzyl cellulose is proposed herein for the treatment of open karst, jointed and fractured rock, open-work gravel, and permeable sediments. A series of laboratory experiments were performed to design an anti-wash out grout suitable for grout injection of coarse aggregates depicting partially and open-jointed saturated rock mass and grouting concrete aggregates for underwater construction. The Taguchi orthogonal array was used to obtain nine different grout mix ratios. A total of four variables were considered, each with three different levels of the water–cement ratio, slag, and dosage of additives such as the superplasticizer and methyl benzyl cellulose. The laboratory determination of grout characteristics recording of mini slump, temperature, pH, visual assessment of grout dispersion, bleeding, and initial setting time and as well as uniaxial compressive strengths and permeabilities of the hardened grout samples were tested. To evaluate the suitability of the grout mixes, an analysis of variance was used for factor analysis and Grey relational analysis (GRA) was used to determine the optimal grout mix design. Based on the GRA, the following levels of the factors afforded the best results: water level 1 (0.3%), SP level 3 (0.01%), methylbenzyl cellulose level 2 (0.002%), and slag level 3 (0.1%). This paper describes the research methodology, detailed research observations, and analyses involved in designing the appropriate concrete mix. Based on the conclusions, relevant commendations regarding the suitability of grout testing equipment and grout mix designs are presented. [ABSTRACT FROM AUTHOR]