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Showing 3 results for Ami ahmadi
Hesam Ami ahmadi, Borhan Beigzadeh,
Volume 17, Issue 4 (6-2017)
Abstract
Controlling the path of drugs movement is one of the processes that can effectively help to treat a variety of diseases. For example, in chemotherapy, small fraction of drug is delivered to the cancer cells and other amounts cause destruction of healthy tissues of body, as a result, before destruction of tumors, the body will be destroyed. Hence we cannot remove tumors from body completely. If we are able to control the path of drugs, we could remove tumors with the least injury. One of the ways through which we can control the movement of the drugs is MDT. In this project, we inspect movement of magnetic particles in the blood and their interactions with consideration of constant magnetic field gradient. After governing its equations and presenting a good model for the forces between particles we simulate these processes in the fluent software. The model we used here is a vein with 8 mm diameter. The simulation was done over 8 cm length of the vein, and from the moment of injection. The base fluid is blood which is considered none-Newtonian fluid. Distribution of magnetic particles in the base fluid has been governed by multiphase approach. The simulation results show that residence time of drug in the presence of magnetic field, increases which in turn increases the possibility of drug absorption.
S.m. Hosseinalipoor, H. Ami ahmadi, A. Ebadi, M. Abdollahi Gol,
Volume 20, Issue 1 (January 2020)
Abstract
Nowadays, the interaction of oil droplets with gas bubbles plays an important role in many industrial, environmental and biological processes. Therefore, in this paper, the outcome of a collision between a silicon oil droplet and an air bubble in water has studied in order to identify the effective parameters in this process. For this purpose, an especial setup was built and four series of experiments in both dynamic (in which the relative velocity of collision is equal to the bubble velocity due to the Buoyancy force) and static conditions were carried out. The results of these experiments were presented and discussed in the form of several tables and pictures. In these experiments, a high-speed camera and image processing were used to gain a better understanding about bubble-drop coalescence qualitatively, and to obtain some quantitative information such as contact time, velocity, and kinetic and interfacial energies of bubbles and drops during the impact. The results of this study show that in addition to the spreading coefficient, the kinetic energy of bubble/droplet in the collision and their contact time, are also determinative parameters in the determination of the outcome of a collision. In the dynamic and static states, the effect of kinetic energy and contact time are more effective, respectively.
H. Ami ahmadi, A. Ebadi, S.m. Hosseinalipour ,
Volume 20, Issue 8 (August 2020)
Abstract
Nowadays, the interaction between gas bubbles and oil droplets plays an important role in the efficiency of many industrial processes. Therefore, it is of great importance to study the influencing factors on these processes. So, in the present paper, the effect of droplet and bubble size on the drainage time of the trapped intervening film between droplet and bubble was investigated. Six series of experiments were conducted for various sizes and three characteristic time scales including drainage time, coverage time, and rupture time were measured. Each of these experiments was repeated at least five times. The results showed that the drainage time changed independently of the droplet/bubble size. Moreover, it was observed that due to the nature of the phenomenon, the measured drainage times in each equivalent size are notably scattered, which means that the microscopic interactions in the water film and between bubble-droplet interfaces have significant impacts on the drainage time. Also, in the current experiment, it was found that the volume of the intervening film between droplet and bubble has no vital role in the drainage time of the mediate water film.
