Showing papers by "Sreenivas Jayanti published in 2013"
TL;DR: In this paper, an integrated configuration of a fuel cell and an auto-thermal ethanol reformer has been studied conceptually for high temperature (HT) and low temperature (LT) polymer electrolyte membrane fuel cells (PEMFCs) for a 5kW, stand-alone power unit.
45 citations
TL;DR: In this article, the authors investigated the effectiveness of an external coolant system using a multiscale, stack heat transfer model on a commercially available computational fluid dynamics (CFD) computer code which takes account of the convective and conductive heat transfer occurring through various layers of the cell and stack elements of an HT-PEMFC operating at 473 K (200 °C).
29 citations
TL;DR: In this article, the effect of spacer grids on flow and heat transfer in rod bundles was investigated using the Eulerian-Lagrangian framework for calculating single-phase, vapour-only flow as well as the droplet-laden flow through a typical bundle geometry.
25 citations
TL;DR: In this paper, the authors present an efficient, computational fluid dynamics (CFD)-based shape optimization method which results in lesser pressure drop and more streamlined flow while adhering to site-specific constraints in terms of the extent of changes that can be made.
Abstract: Sudden changes in the flow direction are quite common but are inevitable in the lay-out in gas ducting in process and power plants. While it is well known that such changes lead to high pressure drops and flow separation, the scope for optimization is limited by constraints such as on-site fabrication and lay-out limitations. In the present paper, we present an efficient, computational fluid dynamics (CFD)-based shape optimization method which results in lesser pressure drop and more streamlined flow while adhering to site-specific constraints in terms of the extent of changes that can be made. The method is based on velocity defect in the plane of the bend: if, at a particular streamwise location, the average velocity in one half of cross section is above (or below) the cross sectional average velocity by, say, 10% or more, then the width of the duct locally is increased (or decreased), if it is possible to do so within the lay-out restrictions. An iterative application of this criterion using a commercial CFD code is shown to lead to better design of the bend. The optimized solution is validated with experimental results.
8 citations
TL;DR: In this paper, a heat transfer-only model was proposed to calculate the safe heat flux for a flat, downward-facing patch of a nuclear power plant, taking into account the conduction within the plate and the convective and boiling heat transfer to the surrounding liquid medium.
1 citations