Filmwise condensation on micro-fin surfaces produced by selective laser melting

This paper presents an experimental investigation on the condensation of steam on vertical flat surfaces with arrays of micro-fins. Three micro-fin surfaces (MF1, MF2 and MF3) of the same fin diameter and fin height but with different fin pitch were fabricated by selective laser melting. The surfaces were tested in a condensation chamber where the gravity driven condensate flow and vapor velocity are orthogonal to one another. The effects of fin pitch and vapor velocity on the heat transfer performances of the surfaces were examined. Our results suggest that fin pitch has significant influence on the condensate drainage path as compared to the increase in heat transfer area. In addition, above a certain wall subcooled temperature, the increase in vapor velocity also resulted in the systematic increase in condensation heat flux indicating the significant effects of vapor shear force. In all, up to 1.4 times enhancement in the heat transfer coefficient was achieved with the micro-fin surface with a fin pitch of 300 μm as compared to a plain Al-6061 surface at constant vapor velocity.Papers presented at the 13th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Portoroz, Slovenia on 17-19 July 2017 .International centre for heat and mass transfer.American society of thermal and fluids engineers

Enhanced thermal performance of a water-cooled cold plate with porous inserts fabricated by selective laser melting

The paper presents an experimental investigation of the thermal and hydraulic performance of a new class of porous metallic foams with ordered arrangements of the Rhombi-Octet unit cell design for use in a water-cooled cold plate. Selective laser melting (SLM) was employed to fabricate the porous metallic foams of two different unit cell sizes. A closed-loop chilled water test facility was set up to perform the experimental investigation and the results of the SLM fabricated porous metallic foams were compared with those of a commercially available metallic foam of random tetrakaidecahedron-like unit cell structures. The permeability (K) and inertia coefficient (CE) of the various metallic foams were characterized using the Forchheimer-extended Darcy equation and it was determined that K can be enhanced by 3.3 times with an increase in unit cell size of the Rhombi-Octet design from 5 mm to 10 mm. In addition, the Rhombi-Octet metallic foam insert also exhibits up to 91% enhancement in the heat transfer coefficient (have) as compared to the empty channel cold plate and up to 47% as compared to the commercial metallic foam insert.Papers presented at the 13th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Portoroz, Slovenia on 17-19 July 2017 .International centre for heat and mass transfer.American society of thermal and fluids engineers

Implications of serial measurements of natriuretic peptides in heart failure: insights from BIOSTAT‐CHF

No abstract available

A robust and accurate drain current I-V model for MESFET

Asia-Pacific Microwave Conference Proceedings, APMC1236-23

A novel drain current I-V model for MESFET

10.1109/22.993423IEEE Transactions on Microwave Theory and Techniques5041188-1192IETM

The formation of aldehydes from the photochemically activated reaction of Cp*Ir(CO)(Cl)(CH2R) complexes with water

10.1016/j.jorganchem.2012.11.030Journal of Organometallic Chemistry724275-280JORC

Hydrodynamic friction reduction in a MAC-hexadecane lubricated MEMS contact

10.1007/s11249-012-0056-zTribology Letters491217-22

Characterization and reduction of MEMS sidewall friction using novel microtribometer and localized lubrication method

10.1109/JMEMS.2011.2159094Journal of Microelectromechanical Systems204991-1000JMIY