An analysis of the effect of orientation on the heat transfer in a scaled model pin fin heat sink utilized in Light Emitting Diode (LED) lighting has been carried out using numerical method. The present study involves natural convective heat transfer that takes place in particular heat sink. A pin fin type heat sink has been studied since they are widely used in LED lighting systems which in tu...

Abstract Additive manufacturing (AM) has an affinity with topology optimization to think of various designs complex structures. Hence, this paper aims optimize the design a lattice-structured heat sink, which can be manufactured by AM. The objectives are maximize thermal performance convective transfer in natural convection simulated computational fluid dynamics (CFD) and minimize material cost...

Design of machine components plays a vital role in the field of Engineering where it includes the shape of component, size, applied loads, position and materials used. Due to the applied loads namely static, thermal and combined loads etc., the component undergoes stresses and deformations which effects the life of component and also the system.The Finite Element Method (F.E.M) is a numerical t...

Astyanax douradilho, new species, is described from the rio Tramandaí system, coastal drainage of Rio Grande do Sul State, Brazil. The new species is distinguished from its congeners by possessing 37-39 perforated scales along the lateral line, 3-5 maxillary tricuspid teeth, 22-24 branched anal-fin rays, absence of a conspicuous dark stripe from humeral region to caudal peduncle, two vertically...

Natural convection heat transfer was investigated experimentally in a concentric-cylinders annulus. To enhance the rate of heat transfer, pin fins were installed on the surface of the inner cylinder. Two fin arrangements were employed, namely, staggered and in-line arrangements. The length of the fins varied from 2 to 8 cm and the Rayleigh number Ra changed in the range from 5 x 105  to 5 x 106...

This work experimentally investigates the effect of vapour velocity during condensation of a ref rigerant on the outside of a single horizontal enhanced tube with particular reference to the fluid-dynamic mechanisms indu ced by vapour shear stress, surface tension and gravity on the condensate flow. More than 70 experimental runs were done in a transparent test section in order to directly o bs...

In this study, the frozen stress photoelastic method was used to investigate the three-dimensional effect on the crack growth behavior in a centrally perforated circular cylinder under internal pressure. The inner surface of the cylinder had a star shape, which consisted of six fins. The specimens were capped at the ends and pressurized internally above critical temperature after real cracks we...