In this study, the continuous separation of hexane and water in micro-systems was investigated. For this purpose, two dimensional glass microfluidic chips were fabricated using laser ablation and thermal bonding method. The chips comprised of a main microchannel and few lateral micro channels. It was aimed to exit hexane and water from the, respectively, main and lateral micro channels. It was found that decreasing the width and increasing the number of the lateral micro channels, and increasing the flow rate of water result in increased separation. Also, increasing the flow rate of hexane and increasing the length of the lateral micro channels result in the reduction of the separation. In order to increase the operating flow rate of the capillary separation, three-dimensional microfluidic chips were fabricated by parallelization of four microscale capillary separators. With the three-dimensional microfluidic chips, the separation efficiency of up to 60% was achieved at the operating flow rate of 1. 5 mL min-1.

Due to immiscibility of the most polymer blends, the present article relies on review the theories and relation between morphology and rheology of immiscible polymer blends. The results of morphological investigation revealed that the ultimate structure of immiscible polymer blends relates to two parameters of viscosity ratio and capillary number. Capillary number connected to matrix viscosity, strain rate and interfacial tension as well. The other parameter which affects on drop break-up and morphology of polymer blends is type of flow. The outcomes indicated that droplet breaks-up in elongation flow easier than shear flow. The models of Palierne, Coran, Jarzebski and Doi- Ohta are very famous models in correlation between rheology and morphology of immiscible polymer blends. It was illustrated in Doi- Ohta model the more differences in first normal stresses of immiscible polymer blends the smaller of droplet size of dispersed phase. In Palierne model, the complex modulus of immiscible polymer blends relates to droplet diameter and interfacial tension.

The aim of this study is to provide a method of making ultralight open cell copper foam with high surface area using chemical procedures. Among the various methods of making open-cell metal foams, electrodeposition method is selected because it can be done in a clean way and is cheaper than other methods. In this method, an open cell polyurethane sponge was used as substrate. Then by choosing appropriate chemical solutions with specific technical knowledge, first polyurethane surface has activated and then by electroless-deposition method, polyurethane activated surface covered with a thin layer of copper. In the final stage, with the aid of electrodeposition the thickness of copper layer was increased to the desired thickness with a minimum required strength. The results show that electrodeposition can increase the thickness of copper layer from 3-5 microns that is obtained in electroless-deposition method to above100 to 150 microns. SEM results show that the micro structure of the deposited layer is globular. By controlling the thickness of deposited copper in electroplating, the surface area of the copper foam can be increased. According to results optimum time for electroless-deposition is between 5 to 7 minutes and for electrodeposition is 1 hour. The open-cell copper foam that is produced in this research is ultralight and due to it high surface can transfer heat with high rates.

Cross flows and molecular diffusion are of high importance in recovery of bypassed oil. Thus, reinforcing viscous cross flow as a driving force in order to increase the oil recovery is proposed. In order to strengthen viscous cross flow, injection of a viscose fluid such as foam in fractured micromodels was applied, and bypassed oil was recovered. Based on the results, effective mechanisms of bypassed oil displacement were viscous cross flow and emulsion. Moreover, two distinct region were observed in displacement front: a dynamic region in which the saturation of foam is low and participation of surfactant saturation is higher than gas phase, and a static region that foam saturation is high and fluids’ mobility are lower than dynamic region. In dynamic region, some oil was recovered by emulsion. The oil droplets flew through arc-like aqueous phase and accumulated near the downstream. As oil saturation decreases in fracture, an area that is known as mixing zone is observed in middle parts of matrix-fracture interaction. Moreover, pressure drop in the main stream is the driving force for moving these oil droplets through arc-like front. This pressure drop is constant in a steady state foam injection in porous media. Hence, the driving force is constant and strengthens the fluid flow up to a certain level in dynamic region. Therefore, each pressure drop in the mainstream corresponds with particular foam invasion depth and is proportional to an individual recovery factor.

The paper deals with the flow of two immiscible couple stress fluids between two homogeneous permeable beds. The flow is considered in two zones: zone I and II contain free flow of two immiscible couple stress fluids between two permeable porous beds at the bottom and top. The flow in the free channel bounded by two permeable beds is assumed to be governed by Stokes’s couple stress fluid flow equations and that in the permeable beds by Darcy’s law. The continuity of velocity, vorticity, shear stress and couple stress are imposed at the fluid-fluid interface and Beavers-Joseph (BJ) slip boundary conditions are employed at the fluid-porous interface. The equations are solved analytically and the expressions for velocity, skin friction and volumetric flow rate are obtained. The effects of the physical governing parameters on velocity are investigated.