Photothermal and Heat-Transfer Properties of Aqueous Detonation Nanodiamonds by Photothermal Microscopy and Transient Spectroscopy

The paper presents experimental results which show significant changes of the intake manifold air temperature during fast tip-in/tip-out engine transients. An adequate two-state polytropic manifold model is developed and experimentally validated. An emphasis is on the derivation and parameterization of a time-variant structure of the heat transfer coefficient. The polytropic manifold model is extended to a three-state form for the more general case of different heat transfer properties for the manifold plenum and runners. An influence of the engine back flow on the runner thermal transients is observed. A simple extension of the three-state model with the back flow effect is proposed.

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Structuring zeolite bodies for enhanced heat-transfer properties

Microporous and Mesoporous Materials ◽

10.1016/j.micromeso.2015.01.028 ◽

2015 ◽

Vol 208 ◽

pp. 196-202 ◽

Cited By ~ 11

Author(s):

Lars Borchardt ◽

Nina-Luisa Michels ◽

Torsten Nowak ◽

Sharon Mitchell ◽

Javier Pérez-Ramírez

Keyword(s):

Heat Transfer ◽

Enhanced Heat Transfer ◽

Transfer Properties

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An Analytical Study to Compare the Heat Transfer Performances of Water-Based TiO2, SiO2, TiC and SiC Nanofluids

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.408.119 ◽

2021 ◽

Vol 408 ◽

pp. 119-128

Author(s):

Md Yeashir Arafat ◽

Shashwata Chakraborty

Keyword(s):

Heat Transfer ◽

Thermophysical Properties ◽

Figure Of Merit ◽

Analytical Study ◽

Convection Heat Transfer ◽

Effective Density ◽

Dispersion Effects ◽

Water Based ◽

Laminar And Turbulent Flow ◽

Transfer Properties

The thermophysical properties as well as the thermal performance of a nanofluid can be altered upon varying the nanoparticle type and/or nanoparticle volume concentration. Herein, the effects of variable nanoparticle concentration on water-based TiO2, SiO2, TiC, and SiC nanofluids have been studied analytically. The dispersion effects of 1-4% nanoparticle on the single-phase forced convection heat transfer performance of the nanofluids have been investigated. The effective thermophysical properties of the nanofluids are determined adopting the general correlations. The flow velocities of the nanofluids relative to their base fluids are assumed to be constant. Mouromtseff number has been employed as a convenient figure of merit to compare the nanofluids under fully developed internal laminar and turbulent flow conditions. The results indicate an increase in effective density, thermal conductivity, and dynamic viscosity of the nanofluids. Nanofluids containing carbide suspensions exhibit superior heat transfer properties compared to those having oxide suspensions.

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