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A numerical study of entropy generation in dissipative and radiative Casson hybrid ferrofluid past a thin needle

Abstract The interest of raising thermal conductivity and optimizing industrial based materials for an enhanced efficiency and productivity has propels various studies on nanomaterials and non-Newtonian fluids. The uses of nanotechnology in technological advancement and industrial promotion could not be overstressed. Thus, the aim of this study is to numerically investigate the entropy formation, heat propagation and conduction of hybridized Casson ferrofluid with dissipation and radiation in a thin needle. The inherent heat transfer capability of magneto-hybridized Fe2O3 and Al2O3 solid nanoparticles in H2O based solvent motivated the study. The streaming nanofluid is controlled by magnetic field, heat generation and continuous stretching velocity. A partial derivative mathematical model is developed to describe the flow dimensions, and via similarity quantities, an invariant transformation of the model is obtained. A numerical and localized spectral linearization scheme is adopted for the thermodynamic and parameters sensitivities analyzes of the thermal fluid. As observed, the heat transfer comparison rate establishes that the thermal propagation of Fe2O3-Al2O3/water is 8.28% higher than Al2O3/water at 0.01% of volume fraction. The entropy formation is raised with rising nanoparticle size, and radiation and dissipation terms boosted temperature distribution.

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The reactions of some <i>ortho</i>‐substituted anilines with various α,β‐acetylenic ketones. A route to substituted quinolines

AbstractThe reactions of some ortho‐substituted anilines with various α,β‐acetylenic ketones were investigated as a route to 4‐alkyl‐, 4‐aryl‐, 4‐hydroxy‐, and 4‐amino‐3‐quinolyl ketones. The anilines examined were 2‐aminoacetophenone (1), 2‐aminobenzophenone (2), anthranilonitrile (3), methyl anthranilate (4), and ethyl anthranilate (5). The acetylenic ketones used were 1,4‐diphenyl‐2‐butyne‐1,4‐dione (6), 3‐butyn‐2‐one (7), 1,3‐diphenyl‐2‐propyn‐1‐one (8), and 4‐phenyl‐3‐butyn‐2‐one (9). The acetylenic ketones typically reacted with the anilines to give enamines; however, exceptions were found. Acetylene 6 reacts with 3 to give the enamine (13) along with a small amount of 2,3‐dibenzoyl‐4‐quinolamine (14). The reactions of 1 or 2 with 6 give the respective quinoline derivatives directly. Acetylene 8 reacts with 2 to give 3‐benzoyl‐2,4‐diphenylquinoline (22) directly, whereas no reaction occurs between 8 and 1 or 3. Acetylene 9 does not react with 1, 2, or 3. The enamines exist as the intramolecularly hydrogen bonded isomers and usually undergo cyclization with 5 molar equivalents of methanolic sodium methoxide to give quinoline derivatives. The 4‐quinolinols exist predominantly as the 4‐quinolinone tautomer.

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