Heat and mass transfer, in this paper, is considered in one-row heat exchanger, that fins are hotter than air flow and water is added to fins. Related governing equations are derived by analyzing a two-dimension model in a unique cell of a heat exchange. These equations are numerically solved by finite difference method. Heat transfer and efficiency under partially wet surface are calculated by...

a numerical investigation of forced convection in a channel with hot solid block inside a square porous block mounted on a bottom wall was carried out. the lattice boltzmann method was applied for numerical simulations. the fluid flow in the porous media was simulated by brinkman-forchheimer model. the effects of parameters such as porosity and thermal conductivity ratio over flow pattern and t...

Novel architectures with nanometric are very promising as building blocks for future nanotechnological applications. Metallic substrates with ordered morphology have been shown to be very effective for surface-enhanced Raman scattering (SERS). The sensitivity of detection is increased by several orders of magnitude by using this technique. In this paper we investigate SERS on thermal evaporated...

A combined experimental and theoretical investigation was conducted to examine the thermal conductivity of layers of wire mesh screen. Employing a carefully controlled sintering process, layers of sintered wire screen were examined experimentally. The experimental results indicate that the effective thermal conductivity in the z-direction (i.e., normal to the plane of the wire screen layers) fo...

Metal coating, metal materials are of two or more layers. The coating metals are widely used in industry. These sheets or saving performance and cost effective solution or both the user. Performance coating metals according to usage in structural applications, settings thermal expansion of the thermo-mechanical control (thermostat), electrical, magnetic, corrosion resistant, flowering and decor...

The sensor characteristics of a coated Fiber Bragg grating (FBG) thermal sensor for cryogenic temperatures depends mainly on the coating materials. The sensitivity of the coated FBG can be improved by enhancing the effective thermal strain transfer between the different layers and the bare FBG. The dual coated FBG’s has a primary layer and the secondary layer. The primary coating acts as an int...

Heat transfer through the gas diffusion layer (GDL) is a key process in the design and operation of a PEM fuel cell. The analysis of this process requires determination of the effective thermal conductivity. This transport property differs significantly in the through-plane and in-plane directions due to the anisotropic micro-structure of the GDL. In the present study, a novel test bed that all...

in this investigation the silicate nano structure of mcm-41 has been used for the production of nanofluid.the particles have negligible heat conductivity and therefore by their dispersion in a base fluid likewater, it is possible to study the increase of heat conductivity due to the brownian motion effects. in thiswork a suitable apparatus for the measurement of heat conductivity has been built...

We have investigated experimentally the thermal conductivity of suspended twisted bilayer graphene. The measurements were performed using an optothermal Raman technique. It was found that the thermal conductivity of twisted bilayer graphene is lower than that of monolayer graphene and the reference, Bernal stacked bilayer graphene in the entire temperature range examined (∼300-700 K). This find...

Heat transfer through the gas diffusion layer (GDL) of a PEM fuel cell is a key process in the design and operation a PEM fuel cell. The analysis of this process requires determination of the effective thermal conductivity as well as the thermal contact resistance between the GDL and adjacent surfaces/layers. In the present study, a guarded-hot-plate apparatus has been designed and built to mea...