This study utilizes silver nano-fluid filled flat heat pipe. It is aimed at effect of various concentrations on flat heat pipe thermal performance by air-cooling testing equipment. The particles used in these experiments were silver particles 35 nm in size. The base working fluid was pure-water. Nano-fluids were prepared using a two-step method. In the experiment, the thickness and length of th...

Heat transfer improvement in circular pipe by using nanofluid and twisted tape is presented in this review paper. Experimental and numerical studies are incorporated involving both the range of turbulent and laminar flow. Effect of type and volume fraction of nanofluid on performance of heat transfer was referred along with the length and twist ratio of the tape through the pipe on heat transfe...

In the present study, heat transfer and entropy analysis for flow through a pipe system is considered. The Reynolds number and the pipe wall temperature effects on entropy distribution and total entropy generation in the pipe are investigated. Numerical scheme employing a control volume approach is introduced when solving the governing equations. Steel is selected as pipe material, while water ...

Heat transfer from the internal surfaces of a vertical pipe to the adjacent air gives rise to the air flow establishment within the pipe. With the aim of optimizing the convective air flow rate in a vertical pipe, the details of the flow and thermal fields were investigated in the present study. Conservation equations of mass, momentum, and energy were solved numerically using simple implicit f...

This paper experimentally studies the heat absorption performance of a heat sink with vertical embedded heat pipes in the aluminum blade. The cooling system with embedded heat pipes distributes heat from the CPU to both the base plate and the heat pipes, and then transfer heat from fins to the Environment. The thermal resistance and heat transfer coefficient are evaluated for natural convection...

In the present research, the laminar forced convective heat transfer and fluid flow characteristics for Al2O3-water nanofluid flowing in different bend (i.e., 180o and 90o) pipes have been investigated numerically in a three-dimensional computational domain using the finite volume technique. The effects of different pertinent parameters, such as the Reynolds number of the duct, volume fraction ...

one way to increase the heat transfer is to use perforated twisted tapes with different hole diameters, which largely improve heat transfer with an increase in the heat transfer area at the constant volume and more mixed flow. in the previous studies, the effect of nanofluids with perforated twisted tapes is less studied. in this work, the performance of water / iron oxide nanofluid in a double...

A temperature jump in the water traveling through a pipe is delayed by the absorption of heat into the pipe wall. The convective transport of heat by the water and the conductive exchange with the interior pipe wall are described by a singular micromodel. The limiting form is a distributed microstructure model, which is successively better approximated by simpler firstand second-order kinetic m...

Nomenclature Ac collector area (m 2) Cb bond conductance (W/m·K) Cp specific heat (J/K·kg) De external pipe diameter (m) Di internal pipe diameter (m) FR heat removal factor hfi heat transfer coefficient (W/m 2·K) k thermal conductivity (W/m·K) ṁ mass flow rate (kg/sec) Qu useful energy per unit time (W) Ta ambient temperature (°C) Tpm average plate temperature (°C) UL overall heat loss coeffic...