A numerical analysis is carried out in a lid-driven cavity using silver (Ag)-water nano-fluid by keeping different shape of conducting as well as insulating cylinders at the centre. The cavity is heated isothermally by a heater placed at the bottom. The right and the left walls are in insulated condition and the upper cold wall is moving with some constant speed. The thermal performance of the nanofluid with the cylinder is being analyzed at two Richardson number (Ri=0.01, 10), four percentage volume of Ag nanoparticles (0 %, 2 %, 5 %, 8 %), and a constant value of Grashof and Prandtl number as 10 4 and 6.2 respectively. The two-dimensional, incompressible and steady Navier-Stokes equations are solved using the commercially available Finite-volume based software Fluent. It is analysed that the thermal mixing inside the enclosure is highly dependent on the shape of a solid cylinder. Moreover, the insignificant variation in flow and thermal field is observed with change in the thermal boundary conditions (insulation and conduction) of centrally placed solid cylinder for all the range of Richardson number (Ri). With increase in percentage volume of nanoparticle Nusselt number (Nu) increases whereas Ri has reverse effect on Nu.

The Present study is an endeavor to laminar flow heat transfer of Cu-water nanofluid inside a square cavity. The cavity is heated by different length heaters with isothermal boundary condition placed symmetrically on two adjacent sides. The moving lid has low temperature and rest of the boundaries are insulated. A thermally conducting solid cylinder is placed at the center of the cavity. The effect of different parameters, nanoparticles volume fraction (0-0.08), Richardson Number (0.01-10) on the fluid flow and temperature fields have been studied. The average Nusselt number increases with the increase in nanoparticle concentration and size of the heater. The effect of concentration of nanoparticles reduces with decrease in Richardson Number.

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The present study is an attempt to elucidate mixed convection flow in a shear driven enclosure incorporating silver nanofluid with a square cylindrical heat source placed at several locations. The simplicity from the point of view of computational expense has been achieved by carrying out 2-D simulations using the finite volume method. The effects of the change in heat source locations are studied observing the isotherms and average Nusselt number with respect to the concentration of silver in the nanofluid (0%, 1%, 3%, and 5%) and Richardson number (0.01, 0.1, 1 and 10) as decisive parameters. Prandtl number and Grashof number have been fixed to 6.2 and 104 respectively. The investigation is undertaken for five different locations of the square cylindrical heater. The study shows that maximum heat dissipation at higher Reynolds number occurs when the heater is placed near the bottom right corner of the enclosure; whereas in case of low Reynolds number, the heater when placed near the top left a corner of the enclosure yields maximum heat transfer. The investigation also yields a positive correlation between average Nusselt number with increasing silver concentration.

Abstract. The general objective of this study is to estimate the performance of the Horizontal Roughing Filter(HRF) by using Weglin's design criteria based on 1/3–2/3 filter theory. The motive is to reduce the Slow Sand load in the raw water by using HRF as the pretreatment unit, but the main objective is to verify the Weglin's design criteria for HRF with respect to raw water condition. A model was also built with the help of neural network which tries to predict the filter efficiency of the HRF. Three results achieved from the three different models were compared to find whether the experimental HRF output conforms to the other two models. According to the results the results from experimental setup is coherent with the neural model but incoherent with the results from Weglin's formula. As neural models are known to learn a problem with utmost efficiency, the model verification result was taken as positive.

A numerical study of mixed convection in a square enclosure from a heating element to a cold moving wall is performed under the isothermal heating conditions. The heater is placed at the bottom boundary and the cold upper wall moves horizontally towards right side with constant velocity. The lateral walls are insulated. The study includes the thermal performance of nanofluid for various shaped obstacles kept at center of the enclosure. The application of hydro-magnetism with uniform and constant magnetic intensity throughout the bottom wall is considered. The heat convection is studied at two Richardson number (0.01 and 10), four percentage volume of silver nanoparticles (0%, 2%, 5%, and 8%) and four Hartmann number (0, 10, 20, and 50). Grashof number, Prandtl number, and Reynolds number have a constant value of 104, 6.2 and 100 respectively. The obtained results indicate the suppression of heat fluxes with increasing intensity of magnetic field whereas it increases with increasing Richardson number and percentage volume of the nano-material in the base fluid.

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Abstract:The hydrologic adversaries like high magnitude storms, extreme dryness, aridity, more than normal demand for water etc. often cause a huge stress on the storage structures such as reservoirs and check dams. This stress implies a lot of adverse effects on the adjacent population. One of the major causes of floods and droughts were due to the mis-management of stored water during hydrologic adversaries. The present study tries to estimate the distribution of the surplus water in the case of hydrologic adversaries. In this regard, two years of daily discharge data of one of the reservoirs, Panchet, of the river Damodar was randomly selected and grouped into six categories based on their magnitude. Three neural models were built. One out of the three was selected due to better performance validating criteria. The behaviour of the inputs in the case of hydrologic abnormality was configured with respect to the available historical records and applied to the selected model. The output would give the magnitude of surplus in the case of the pre-configured hydrologic adversaries. According to the results, the Panchet reservoir could not mitigate the stress created due to the applied hydrologic adversaries. The study was conducted with a single reservoir and one major hydrologic pattern of the decade. A more detailed study with the help of this approach could further improve the model estimation.