the excellent performance of fluidized bed heat exchangers is due to the interaction between particles and heat transfer surface and to the mixing effects in the viscous sublayer. in this paper, the results of experimental investigations on heat transfer for a wide range of newtonian and non-newtonian (shear-thinning power law) fluids are presented. new design equations have been developed for ...

OBJECTIVE To compare the degree of bacterial circuit colonization, frequency of ventilator-associated pneumonia (VAP), character of respiratory secretions, rewarming of hypothermic patients, disposable costs, and air flow resistance in intensive care patients ventilated using either a heat and moisture exchanger (HME) or hot water (HW) humidifier circuit. DESIGN A prospective, randomized blin...

A Lagrangian computational method is used to explore the performance of heat exchangers in conditions of oscillating flow and oscillating pressure relevant to thermoacoustic devices. Pressure oscillations cause temperature oscillations within the working gas. Depending on phase, these ‘‘pressure-driven temperature oscillations’’ can enhance or degrade heat transfer within the exchangers of a th...

The paper studies optimization of shell-and-tube heat exchangers using the particle swarm optimization technique. A total cost function is formulated based on initial and annual operating costs of the heat exchangers. Six variables – shell inside diameter, tube diameter, baffle spacing, baffle cut, number of tube passes and tube layouts (triangular or square) – are considered as the design para...

The present study investigated the effect of distilled-water/ silver nanofluid on heat transfer in a closed cooling system of one of the electrical energy generation units at Isfahan power plant. The difference between this study and previous researches refers to silver properties which have a high thermal conductivity and is non-toxic, hydrophilic and eco-friendly. Distilled water/ silver ...

The forced convection experiment of fan plate-finned tube heat exchangers which are mainly used in air conditioners and the forced convection model have been studied for which the heat transfer effect of this type exchangers has not been proposed by a model. All measurements were made when there is no refrigerant flow in the pipe at Reynolds's number of 580. According to the experiment results,...

This paper demonstrates the use of poly(dimethylsiloxane) (PDMS), polyurethane (PU), epoxy, and poly(methyl methacrylate) (PMMA) as mandrils to fabricate metallic heat exchangers having 300–700 m internal channels. The mandrils were prepared using two soft lithographic techniques-replica molding, and microembossing. To fabricate the heat exchangers, the polymeric mandrils were coated with a thi...