ISSN Online: 2688-7231
ISBN Online: 978-1-56700-478-6
EXPERIMENTAL INVESTIGATION OF ORTHOGONAL MULTI-JET AIR IMPINGEMENT ON COMBINED DIMPLE AND PIN-FIN HEAT SINK
摘要
The research is a fundamental investigation of heat transfer to
an impinging air jet. Jet impingement is known method for high heat transfer coefficients. The most important objective of
the current research wok is to conduct an investigation of the
heat transfer mechanisms for an impinging air jet for
combined heat sink with pin fin and dimpled surface.
The methodology of the research work is to make the use of jet
air impingement to find heat transfer enhancement in dimpled
flat target surface and pin fin flat surface. A target plate and its sidewalls were hung from the nozzle plate. The distance
between the nozzle plate and the target plate (Z/D) was
adjusted in between 4, 6 and 8 jet-diameters. Acrylic plate
sidewalls were installed or removed to change the cross flow
schemes such as, minimum, intermediate and maximum spent
air exits.
The following sample graphical results show the comparisons
between various pin-fin array arrangements similar to dimple
surface for maximum spent air. Where Heat Sink 1:- 8 mm pin
diameter, Heat sink 2:- 6 mm pin diameter, Heat sink 3:-
8 mm pin diameter.
Nu =Nusselt Number, Re= Reynolds Number, Z= Height of Nozzle from heat sink, D= Nozzle diameter.
It has been seen from graph that pin fin 6 mm at transfer
augmentation for all Z/D ratios. Heat sink two with dimple 6
mm diameter and staggered arrangement of dimples shows
maximum augmentation at Re = 6000. Further investigation
in heat transfer enhancement for combined dimple and pin fin
is to be carried out by experimentation