Other affiliations: Indian Institutes of Technology
Bio: Ranjith Mohan is an academic researcher from Indian Institute of Technology Madras. The author has contributed to research in topic(s): Dynamic soaring & Flatness (systems theory). The author has an hindex of 3, co-authored 19 publication(s) receiving 62 citation(s). Previous affiliations of Ranjith Mohan include Indian Institutes of Technology.
01 Oct 2013-Journal of The American Helicopter Society
22 May 2014-Computers & Fluids
Abstract: We describe the use of a spectral collocation method to compute the characteristics of incompressible, viscous flow in a lid driven right triangular cavity with wall motion away from the right angle. First, the 2-D Gauss–Lobatto grid on the square [ - 1 , 1 ] × [ - 1 , 1 ] is mapped to a triangular domain by means of a singular mapping. A singularity subtraction technique is used to account for the most singular terms of the asymptotic expansions near the top corners of the flow. The unsteady Navier–Stokes equations in the vorticity–streamfunction formulation are then solved in this transformed grid using an influence matrix technique. A third order Adams Bashforth/Backward differentiation method appears to provide excellent numerical stability for the scheme and also permits a larger critical time step. Detailed characteristics of the flow and comparisons with published results are presented.
01 Nov 2018-Aeronautical Journal
Abstract: The flatness of a six-degree-of-freedom (6DoF) aircraft model with conventional control surfaces – aileron, flap, rudder and elevator, along with thrust vectoring ability is established in this work. Trajectory optimisation of an aircraft can be cast as an inverse problem where the solution for control inputs that yield desired trajectories for certain states is sought. The solution to the inverse problems for certain systems is made tractable when they exhibit differential flatness. Flatness-based trajectory optimisation has a significant advantage over an equivalent collocation-based method in terms of computational efficiency and viability for real-time implementation. An application for the flatness of 6DoF aircraft is shown in the trajectory optimisation for dynamic soaring, and its connection with an equivalent 3DoF flatness-based implementation is also brought out. The results are compared with that from a collocation-based approach.
01 Apr 2012-Journal of The American Helicopter Society
25 Jun 2018-
Abstract: Numerical study of mixed convection in a partially heated nanofluid-filled lid driven cavity with internal heat generation and having a partial flexible wall was performed. The bottom wall of the triangular enclosure is moving with constant speed and left vertical wall is partially heated. The inclined wall of the cavity is cooled and partially flexible. The governing equations are solved with Galerkin weighted residual finite element method. The effects of Richardson number (between 0.05 and 50), internal Rayleigh number (between 10 4 and 10 8 ), size and elastic modulus of the partial flexible wall and nanoparticle volume fraction (between 0 and 0.04) on the fluid flow and heat transfer were numerically investigated. It was observed that the local and averaged heat transfer reduce as the value of the Richardson number and internal Rayleigh number increase. As the value of the elastic modulus of the inclined wall and nanoparticle volume fraction increase, local and average heat transfer enhance. The discrepancy between the averaged Nusselt number increase for different sizes for the lower values of elastic modulus of the flexible wall. When heat transfer process is effective adding nanoparticles to the base fluid is advantageous.
01 Nov 2016-Journal of Magnetism and Magnetic Materials
Abstract: In this numerical study, magnetohydrodynamics natural convection in a flexible sided triangular cavity with internal heat generation is investigated The inclined wall of the cavity is cooled and flexible while the left vertical wall is partially heated Galerkin weighted residual finite element method is used to solve the governing equations The effects of pertinent parameters such as external Rayleigh number (between 104 and 106), internal Rayleigh number (between 104 and 107), elastic modulus of flexible wall (between 500 and 105), Hartmann number (between 0 and 40) and inclination angle of the magnetic field (between 0° and 90°) on the fluid flow and heat transfer characteristics were numerically investigated It was observed local and averaged Nusselt number enhance with external Rayleigh number but in the vicinity of the upper location of the heater local heat transfer deteriorates due to the inclined wall deformation with increasing external Rayleigh number Heat transfer reduces with internal Rayleigh number and Hartmann number Averaged heat transfer decreases 1325% when internal Rayleigh number is increased from 104 to 107 and decreases 4056% when Hartmann number is increased from 0 to 10 The reduction in the convection with magnetic field is effective for higher values of external Rayleigh numbers and averaged heat transfer increases with magnetic field inclination angle
01 Jan 1974-
01 Mar 2019-International Journal of Mechanical Sciences
Abstract: The present work examines the two-dimensional, steady, laminar mixed convective fluid circulation and heat transfer in a square lid-driven cavity influenced by the change in the location of the triangular block with constant heat flux (CHF) thermal condition. The effect of the changes in the location of block along the vertical centerline ( x = 0.5 , y ) of the cavity has been explored. The dependence of various flow governing dimensionless parameters, such as, Reynolds number ( R e = 1 − 1000 ) , Richardson number ( R i = 0.01 , 1 , 10 ) , blockage ( B = 0.1 , 0.2 , 0.3 ) and location ( L y = 0.25 , 0.5 , 0.75 ) of triangular block on the streamline, temperature contours, Nusselt numbers, etc. has been illustrated. A normalized Nusselt number is also calculated for studying the difference in heat transfer rate with that of constant wall temperature condition. The results of the study indicates higher heat transfer rates for centered block position ( L y = 0.5 ) than remaining two ( L y = 0.25 , 0.75 ) . For a given blockage, Nusselt number shows decline with increasing Ri. The summary of research is expressed by using two forms of empirical correlations ( N u ¯ = f ( L y , R e ) ) , N u ¯ = f ( B , R e ) for possible utilization in engineering design.
Author's H-index: 3