Showing papers by "S.V. Prabhu published in 2019"
TL;DR: In this article, the performance of a Darrieus turbine is enhanced using a blocking plate optimally located at the upstream side of the retarding vane, which would enhance the coefficient of power of the turbine.
36 citations
TL;DR: In this paper, the effect of geometry of channel bottom and channel side wall distance on the performance of a Savonius turbine is investigated and a velocity correction methodology is proposed to determine the actual performance of the turbine.
35 citations
TL;DR: In this paper, the effect of dimpled surface configurations on heat transfer was investigated for multiple jets issuing from orifices arranged in a 3'×'3' array, where the distance between the orifice plate and the test surface is varied from 1d to 6d.
21 citations
TL;DR: In this article, the heat transfer characteristics of the impinging methane flame were determined using the minimization technique wherein the target surface is impinged by a methane flame from the bottom and is simultaneously cooled from the top by air jets of different Reynolds number.
14 citations
TL;DR: In this article, the thermal characterization of self-aspirating radial-type domestic gas stove burners is studied for varied inner port swirl angles and an alternate methodology is suggested to evaluate the thermal performance of burners which gives more technical insights in comparison with conventional water loading test.
9 citations
TL;DR: In this article, a partially-filled, rotating pipe with water flowing through it was experimentally investigated to study the effect of various parameters on the rotary evaporator operation, including wall heat flux, inclination angle, and volume flow rate.
7 citations
TL;DR: In this paper, the authors highlight the influence of circular pipe on the shedding characteristics of two-dimensional bluff bodies and discuss the design issues pertinent to vortex flow meters in laminar, transition and turbulent flow regimes.
6 citations
TL;DR: In this article, the effect of flame jet parameters such as mixture Reynolds number, equivalence ratio and burner to target surface spacing on heat transfer characteristics is investigated, and the thermal performance is quantified in terms of thermal efficiency.
Abstract: Thermally efficient gas burners can be designed by optimising the parameters associated with combustion and heat transfer mechanisms. The current study presents the thermal analysis of the premixed methane-air flame jets of circular tube gas burner impinging on a target surface. The effect of flame jet parameters such as mixture Reynolds number, equivalence ratio and burner to target surface spacing on heat transfer characteristics is investigated. The thermal performance is quantified in terms of thermal efficiency. The lean and stoichiometric mixtures release maximum amount of thermal energy. However, in lean flames, a part of the energy released is used for rising the temperature of excess air. Though the combustion is incomplete for fuel rich flames, higher heat transfer is achieved because of higher flame height. The optimal thermal performance is observed when the mixture is near stoichiometric and the burner is spaced from the target surface such that the premixed cone tip just touches the surface.
4 citations
TL;DR: In this article, the authors investigated the behavior of wall heat transfer coefficient with randomized packing of equal aspect ratio cylinders inside a concentric tube heat exchanger and found that the random sphere packing is superior to cylinder packing.
Abstract: Heat transfer enhancement is challenging area in which different techniques are utilized to dissipate the generated heat during operation. Packed beds are devices which enhance heat transport while being compact and are used in several applications such as energy storage, heat exchange devices, catalysis, food processing etc. In the present study, the behavior of wall heat transfer coefficient with randomized packing of equal aspect ratio cylinders is investigated. In this work, the local wall heat transfer coefficient is calculated from local wall temperature data obtained using infrared (IR) thermography in packed beds with randomized packing of cylinders under steady state conditions with water as the working fluid. The randomized packing of cylinders is done inside a concentric tube heat exchanger and the heat transfer enhancement is studied. Experiments are conducted for bed to equivalent particle diameter ratio 2 using random packing of mono-dispersed glass cylinders (dcyl = 6 mm and lcyl = 6 mm). The local wall temperatures are measured using an infrared (IR) camera while the fluid flow takes place through the packed beds. In literature, it is found that wall region contribution to heat transfer is above 90%. The comparison of enhancement in heat transfer for both packing of spheres and cylinders inside concentric tube heat exchangers is done and it is observed that the random sphere packing is superior to cylinder packing.
1 citations
21 Jun 2019
TL;DR: In this article, the performance of the intumescent coating (passive type fire retardant coatings) is studied with the help of cone calorimeter and open pool diesel fire as sources of heat.
Abstract: Accidental fire is a major concern in terms of safety of infrastructures and human lives. With the technological advancement, several novel methods are developed for minimizing the damages caused by the fire. One of the methods is to paint the base metals/ material with fire retardant coatings which can increase the lead time so that economic destruction and loss of human lives can be avoided. In this work, the performance of the intumescent coating (passive type fire retardant coatings) is studied with the help of cone calorimeter and open pool diesel fire as sources of heat. The transient temperature distribution for bare Stainless Steel 310 plate suggests that the cone calorimeter experiments alone cannot suffice for mimicking real life conditions. Comparison of the behavior of the available paints in cone calorimeter and open pool fire confirms that the performance of intumescent coatings in cone calorimeter is very different from that in open pool fire. The safe initial thickness of the intumescent coating is a function of heat release rate of the source. The effective thermal conductivity of the intumescent coatings is evaluated using one dimensional conduction heat equation with constant boundary temperature condition.