Department of Energy Conversion (2014 - Present)
mechanical engineering
Mechanical Engineering, Sharif University of Technology,
Mechanical Engineering,Energy Conversion: Internal Combustion Engines
Mechanical Engineering, Sharif University of Tehnology,
Mechanical Engineering, Thermofluids: Internal Combustion Engines
Mechanical Engineering, Iran University of Science and Technology,
Research field: روش های اندازه گیری
Expert: Vahid Moshfegh
Phone: 02182883505
Address:
My name is Mohammad Zabetian, I was born in city of Natanz in Isfahan province, Iran. Since 2007, I have focused on conducting research projects and enhancing university-industry collaborations. I hope that team work and usage of huge potential of Iran, especially its human resources, result in improvement in scientific and life aspects of humans in Iran and the world.
One of the crucial phenomena to enhance the heat transfer of microchannel heat sinks is the flow mixing and wall interaction through the secondary flow. In the present study, a combination of the wavy and the oblique grooved microchannel patterns was investigated to improve the performance of the microchannel heat sink. The oblique grooves with a pitch of 375 ?m were combined with the wavy microchannel. The effect of fins with widths of 250 and 125 ?m on thermal performance was investigated (Type-1 and Type-2). The amplitude of 250 ?m and wavelength of 2500 ?m were considered for wavy microchannels. Furthermore, the effect of pitches on the heat transfer was studied; subsequently, pitches of 750 and 1500 ?m were analyzed (Type-3 a
Objective: We present a four-branch model of the dielectrophoresis (DEP) method that takes into consideration the inherent properties of particles, including size, electrical conductivity, and permittivity coefficient. By using this model, bioparticles can be continuously separated by the application of only a one-stage separation process. Materials and Methods: In this numerical study, we based the separation process on the differences in the particle sizes. We used the various negative DEP forces on the particles caused by the electrodes to separate them with a high efficiency. The particle separator could separate blood cells because of their different sizes. Results: Blood cells greater than 12 μm were guided to a special branch, which
With progress in technology and miniaturization of electronic devices, liquid coolants were used increasingly in personal computers, laptops, servers, and supercomputers. Micro heat sinks are widely used for cooling rate enhancement. Geometrical design plays a crucial role in the thermal performance of microchannel heat sinks. This work reviews the researches concerning micro heat sinks via three aspects: (1) Flow passage patterns, (2) Geometry of cross-sections (3) Inlet and outlet manifolds containing header shapes and the manifold position. Main specifications of each feature were tabulated to make it appropriate for comparisons. The main aims of this study are to cover the research gap in a review of cross-section impact on the thermo-h
This study proposes a microfluidic device capable of separating monocytes from a type of cancer cell that is called T-cell acute lymphoblastic leukemia (RPMI-8402) in a continuous flow using negative and positive dielectrophoretic forces. The use of both the hydrodynamic and dielectrophoretic forces allows the separation of RPMI-8402 from monocytes based on differences in their intrinsic electrical properties and sizes. The specific crossover frequencies of monocytes and RPMI-8402 cells have been obtained experimentally. The optimum ranges of electrode pitch-to-channel height ratio at the cross sections with different electrode widths have been generally calculated by numerical simulations of the gradients of the electric field intensities
Isolation of microparticles and biological cells on microfluidic chips has received considerable attention due to their applications in numerous areas such as medical and engineering fields. Microparticles separation are of great importance in bioassays owing to the need for a smaller sample and device size, and lower manufacturing costs. In this study, we first explain the concepts of separation and microfluidic science along with their applications in the medical sciences, and then, a conceptual design of a novel inertial microfluidic system is proposed and analyzed. The PDMS spiral microfluidic device was fabricated, and its effects on the separation of particles with sizes similar to biological particles were experimentally analyzed. Th
In the present study, chemiluminescence analysis is used to determine the optimum range for equivalence ratio (Φ) in a multi-hole cylindrical burner. The premixed burner which uses natural gas is widely applied in gas condensing boilers and is examined here by Flame Emission Spectroscopy (FES). A spectrometry setup was implemented to capture emission of the burner, in order to detect OH*, CH*, C2*, and CO2* species by their chemiluminescence. The emission of OH* and CO2* was investigated for different equivalence ratios and burner power showing a peak in the lean ranges of Φ?=?0.77–0.85 and 0.78–0.85 respectively, that corresponds to the maximum heat release rate. In addition, the OH*/CH* intensity ratio was investigated for range of
In this paper, a cylindrical premixed perforated burner which is mostly used in condensing boilers is investigated by image processing methods. The burner is experimentally analyzed in its operating heating capacities (11.7–17.1 kW) and equivalence ratios (0.4–1.2). Flame properties were studied using digital images by CCD camera and color processing techniques. The method devised a procedure for finding a reliable relation between a digital image color and flame characteristics in the visible wavelength domain. It is observed that by decreasing the equivalence ratio from 1.2 to 0.4, the flame color changed from green with yellow and then blue. Besides, flame lift-off and blow off were also observed. Lower flammability limit is in the
The induced flow effect is the rotary motion generated in the fluid flow due to the temperature gradient. The phenomenon of thermophoresis is the movement of particles from the warmer side of the fluid to the cooler side. Laser is a very suitable device for creating a temperature gradient due to its unique features such as high power density, harmonic waves, single wavelength and very low divergence. Thermophoresis phenomenon and induced flow have many uses in the transfer of particles and in various fields such as medicine and industry. In the present work, the phenomena of laser thermal interactions and flows of microparticles were studied. Thermophoresis phenomenon and induced flow were investigated experimentally using laser. Scale anal
The two thermal effects, thermophoresis and photophoresis phenomena that cause particle movements due to thermal gradient through the liquid and thermal gradient through the particle, respectively, have been widely studied over the past years because of their wide range of applications. This thermal gradient can be made by laser beam. There are a few studies concerning these two effects, especially photophoresis, in liquid media. In this paper, these two effects and their induced velocity to particles are studied in liquid media. The affecting parameters on these effects are studied and their effect on particles are determined. Effect of laser parameters like laser power and wavelength in the channel are discussed and the maximum velocity a
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