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Heat transfer enhancement has always been an issue that has plagued the scientific
corridors for decades. Various techniques have been adopted using both active and passage
techniques to reduce the thermal resistance and supplement the heat efficiency. Annular
passages are one of the most commonly used in various industries and engineering systems
due to their simplistic geometry and compact size. Efficiency of such systems have always
been a keen point of interests for researchers and have resulted in advancements that have
resulted in superior heat transfer as compared to primitive methods.
One such advancement has been the introduction of nanofluids in limited concentrations
with a base fluid to circumvent the limitations of the usual fluids used in the annular
passages. A research gap exists in usage of Trihybrid Nanofluids in the annular passages
which greatly enhances the heat transfer while providing greater thermal conductivity,
improved flow and minimal thermal resistance. My research aims to study the effects of
Tri hybrid nanofluids in two different types of annular passage ways (Circular and
Diamond Shape) with inner and outer heating for 4 different Tri hybrid Nano fluids which
are Al2O3, CuO and Fe3O4, Al2O3, TiO2, and SiO2, SWCNT, MWCNT, and TiO2, SiO2,
TiO2, and ZnO, Gr, Ag, and TiO2 , CuO, MgO, and MWCNTs, all of which had a
volumetric concentration of 3 percent and were suspended in water. The effectiveness of
these tri hybrid Nano fluids was gauged by several factors which include calculation of
Nusselt Number, hydraulic performance quantified by pressure drop whilst the heat
transfer from the surface is calibrated by the heat transfer coefficient. An increase of 19.92
% for Nusselt number was observed for TiO2, SiO2, TiO2, and ZnO but the pressure drop
was way too high. In order to study the confluence of these factors a performance
coefficient index was computed through which a tri hybrid Nano fluid (Al2O3, TiO2, and
SiO2) was selected to be coupled with longitudinal vortex generators. The vortex generators
are to be applied at various pitch angles mainly at 20,30 and 40 degrees and tested for all
the performance parameters.