The objective of the present study is the synthesis of MWCNT-TiO2 hybrid nanostructures by solvothermal synthesis method with TiCl4 as precursor. The heat transfer enhancement due to the use of MWCNT-TiO2 nanofluid was investigated. As-prepared hybrid materials were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results showed that MWCNTs were uniformly dec...

this paper presents a simple methodology for cost estimation of a near optimal heat exchanger network, which comprises mixed materials of construction. intraditional pinch technology and mathematical programming it is usually assumed that all heat exchangers in a network obey a single cost model. this implies that all heat exchangers  in a network are of the same type and use the same materials...

Heat transfer coefficient in nucleate pool boiling near critical heat flux at least one orderhigher than the convectional heat transfer modes. In this paper, an experimental setup isdesigned and fabricated to investigate the mechanism of heat transfer from boiling surface tobulk liquid near critical heat flux. The images of pool boiling near the high heat flux regionreveals that the individual ...

In this paper, we present an experimental investigation of pool boiling heat transfer on multiscale (micro/ nano) functionalized metallic surfaces. Heat transfer enhancement in metallic surfaces is very important for large scale high heat flux applications like in the nuclear power industry. The multiscale structures were fabricated via a femtosecond laser surface process (FLSP) technique, whic...

This work presents an experimental investigation of the thermal performance of a flatplate heat pipe during startup and shutdown operations. Using the analytical model developed in a previously study, analytical and experimental results on the effect of input power and cooling heat transfer coefficient on the thermal performance of the heat pipe are presented and discussed. The results indicate...

Experiments were conducted to investigate flow boiling heat transfer to a dielectric fluid in a silicon chip-integrated microchannel heat sink. Twenty-four microchannels, each 389 m  389 m in crosssection, were fabricated into the 12.7 mm  12.7 mm silicon substrate. High-speed visualizations (at 12,500 frames per second) were performed simultaneously with heat transfer and pressure drop mea...

This paper presents and discusses the numerical simulations of transient laminar natural convection cooling of high Prandtl number fluids in cubical cavities, in which the six walls of the cavity are subjected to a step change in temperature. The effect of the fluid Prandtl number on the heat transfer coefficient is studied for three different fluids (Golden Syrup, Glycerin and Glycerin-water s...

High heat transfer coefficients and large interfacial areas make bubble columns ideal for dehumidification. However, the effect of geometry on the heat transfer coefficients outside cooling coils in shallow bubble columns, such as those used in multi-stage bubble column dehumidifiers, is poorly understood. The generallyoverlooked entry and coalescing regions become important in shallow bubble c...

one of the cooling systems that has received considerable attentions in recent years is the adsorption chiller, which works based on the adsorption and desorption of a working fluid in a solid porous bed. different parameters such as fin height directly affect the bed heat and mass transfer processes, and therefore, the performance of the adsorption chillers. in the present study a numerical mo...

Experiments are conducted with a perfluorinated dielectric fluid, Fluorinert FC-77, to identify the critical geometric parameters that affect flow boiling heat transfer and flow patterns in microchannels. In recent work by the authors (Harirchian and Garimella IJMF 35:349-362, 2009), seven different silicon test pieces containing parallel microchannels of widths ranging from 100 μm to 5850 μm, ...