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Item The evaporative drying of a two-dimensional rectangular brick is studied numerically as a conjugate problem. The conservation equations for the solid are obtained using the continuum approach. The Navier-Stokes equations have been employed for obtaining the flow field and the corresponding flow solutions are used for predicting the drying behavior of the brick. The predictions of temperature and moisture content show that the leading edge dries faster compared to other sides of the solid. The full two-dimensional solutions differ considerably from the solutions based on heat and mass transfer through the boundary layers over the top surface. Average heat and mass transfer coefficients appropriate to the conjugate problem have been defined, based on constant temperature and moisture differentials between the solid and the ambient. The corresponding Nusselt and Sherwood number values indicate that analogy does not exist between heat and mass transfer, until the entire brick reaches wet bulb conditions. Free convection effects on drying are also studied for some initial period for low Reynolds number. Due to the influence of buoyant forces imparted by gravity, the overall drying rate has improved. © 2001 Elsevier Science Ltd. All rights reserved.(Elsevier Ltd, A theoretical model of brick drying as a conjugate problem) Murugesan, K.; Suresh, H.N.; Seetharamu, K.N.; Aswatha Narayana, P.A.; Sundararajan, T.2001Item Study on shelter effect of solid wind fences(2011) Umesh, U.; Prashanth, J.; Yaragal, S.C.; Nagaraj, M.K.In this paper the shelter effect of solid wind fence is investigated. A solid fence was considered with different bottom gap ratios (ratio of bottom gap to the height of the fence) of 0, 0.1, 0.2 and 0.3. The numerical analysis was done for different free stream velocities of 7.5 m/s, 10 m/s and 12.5 m/s. The results obtained were compared with the results of wind tunnel testing and flow visualization. Comparison between the experimental and numerical results showed a fairly good agreement. Flow visualization technique provided sufficient information for planning and conducting flow field measurements with a clear demarcation of reattachment length. The modified k- ? turbulence model predicted the flow well. From both the experimental and numerical investigation it is shown that a fence with gap ratio of 0.1 is effective in providing good shelter effect. © 2011 CAFET-INNOVA TECHNICAL SOCIETY. All rights reserved.Item Investigation of 2-d wake pressures downstream of perforated plates(2012) Yaragal, S.C.The construction, calibration and measurements made by a built up static pressure probe for measurement of unsteady pressures in the flow field are discussed. The wind tunnel experiments were conducted on a series of two-dimensional perforated normal plates to an air stream to study the characteristics of unsteady wake pressures and to ascertain if they could be correlated in some way. The velocity ranged from 5 to 15 m/s in the present study. The pressure field gets significantly modified as the perforation level increases. The present study is concerned with three plates with perforation level of 0%, 25% and 35%. There appears to be a correlation between the maximum normalized value of the R.M.S pressure fluctuation levels, base pressure and the perforation level of the normal plate. © 2012 CAFET-INNOVA TECHNICAL SOCIETY.Item Assessment of hydropower potential in Nethravathi river basin using SWAT model(CAFET INNOVA Technical Society cafetinnova@gmail.com 1-2-18/103, Mohini Mansion, Gagan Mahal Road, Domalguda, Hyderabad 500029, 2015) Babar, S.; Shobhita, M.P.; Ramesh, H.Hydropower plants have the advantage of producing renewable and clean power, the renewable and reliable energy source that serves national environmental and energy policy objectives. Therefore, the development of hydropower plant and improvements of water management have essential in contributing to sustainable growth and energy production in developing countries like India. The present study is concerned with the development of methodology and assessment of hydropower potential in the Nethravathi River basin with the help of Remote Sensing and GIS. The drainage area covers about 3190 km2 at Bantwal gauging point, and most of the land cover of the basin is dominated by forest. The basin was divided into six sub-basins based on hydrology and topography using GIS tools. The climate over the basin is coastal humid tropical and receives an average annual rainfall of about 4000 mm. sub-basin discharges were estimated using the Soil Conservation Services (SCS) curve number method. To ensure the total discharge from six sub-basins computed from SCS curve number method, the flows were routed and simulated at the gauging location using Soil and Water Assessment Tool (SWAT). SWAT model was calibrated for monthly time steps from 1998–2001, and validated for 2002–2003. Flow-duration curves (FDC) were generated for each sub-basin to assess the dependable yield. The results have shown a good agreement between observed and the simulated flows. The available discharge at 75%, 80% and 90% of time for each sub-basin were extracted from the FDC. This result were used to calculate the hydropower potential in all the six sub-basins at Q75, Q80 and Q90, by integrating thematic layers using ArcSWAT. © 2015 CAFET-INNOVA TECHNICAL SOCIETY. All rights reserved.Item Performance analysis of novel V-shaped turbine blade profile by three-dimensional numerical investigations with varying overlap ratios for hydropower application(Elsevier Ltd, 2022) Shashikumar, C.M.; Madav, V.In the present paper, three-dimensional numerical simulations were carried out to examine the influence of the overlap ratio between the two straight edges on the advancing and returning blades of the novel V-shaped rotor blade profiles using the sliding mesh technique. The performance parameters were computed with respect to the tip speed ratio. The findings show that the coefficient of torque and power for the novel V-shaped turbine blade is maximum for the zero-overlap ratio compared to the turbine blade, with an overlap ratio ranging from 0.05 to 0.3. The blade profiles' flow field was visualized at different angular positions, and various significant zones developed during the turbine blade rotation were captured and analyzed. The new overlapping jet developed between the two straight edges of the advancing and returning blade profiles as the overlap ratio varies from 0.05 to 0.3. Therefore, the turbine's performance is reduced due to the development of an overlap jet as it travels parallel to the straight edges of the blade profile and does not impact the rear side of the returning blade profile. © 2022 Elsevier Ltd