مسعود رحیمی
هیئت علمی / دانشگاه رازی
[ 1 ] - استخراج پروپیونیک اسید از آب در میکروکانالهای T شکل: اثر طول کانال اختلاط و دبی جریان
در این تحقیق، میکروکانالهای T- شکل برای استخراج پروپیونیک اسید از آب با استفاده از حلال 1-اکتانول به‌کار برده شده است. اثرات طول کانال اختلاط و دبی جریان سیال بر مشخصه‌های انتقال جرم بین دو فاز مورد بررسی قرار گرفت. آزمایش‌ها در چهار میکروکانال با طول‌های 10، 20، 30 و cm40 در شدت جریان‌های بین 2 و mL/min 16 انجام شد. اثر افزایش طول کانال بر ضریب انتقال جرم، بازده استخراج و افت فشار مورد مطالعه...
[ 2 ] - CFD Study on Hydrogen-Air Premixed Combustion in a Micro Scale Chamber
This paper reports a CFD modeling study to investigate the hydrogen-air mixture combustion in a micro scale chamber. Nine species with nineteen reversible reactions were considered in the premixed combustion model. The effect of operational and geometrical conditions including; combustor size, wall conductivity, reactant flow rates and hydrogen feed splitting on combustion stabilit...
[ 3 ] - CFD Modeling Study of High Temperature and Low Oxygen Content Exhaust Gases Combustion Furnaces
This paper reports a CFD modeling study on the possibility of using high temperature and low oxygen content exhaust gases as oxidant for combustion in an industrial furnace by a written computer program. Under these conditions,the predicted results for the flow and heat transfer properties are compared with those under the several cases of conventional and highly preheated...
[ 4 ] - Biodiesel production from soybean oil using ionic liquid as a catalyst in a microreactor
In the present study, Choline hydroxide (ChOH) as an ionic liquid catalyst was used for transesterification of soybean oil into biodiesel in a microchannel reactor. The effects of three variables i.e. reaction temperature, catalyst dosage and total flow rate on fatty acid methyl ester (FAME) content (wt. %) were optimized using Box–Behnken experimental design. In order to predict the FAME conte...
[ 5 ] - Waste water ammonia stripping intensification using microfluidic system
This paper reports the results of experimentally removing ammonia from synthetically prepared ammonia solution using a micro scale mixing loop air stripper. Effects of various operational parameters (such as: pH, air flow rate, wastewater flow rate and initial ammonia concentration) were evaluated. By increasing the pH from 10 to 12.25 the amount of KLa increased from 0.26 to 0.73 hr-1. A consi...
[ 6 ] - Ultrasound-Assisted Biodiesel Production in microreactors
The ultrasound-assisted (UA) soybean oil methanolysis using KOH as a catalyst was studied at different reaction conditions in a microreactor. Box–Behnken experimental design, with three variables, was performed and the effects of three reaction variables i.e. reaction temperature, catalyst concentration and the methanol-to-oil molar ratio on fatty acid methyl ester (FAME) yield were evaluated b...
[ 7 ] - An optimization study by response surface methodology (RSM) on viscosity reduction of residue fuel oil exposed ultrasonic waves and solvent injection
In this study, response surface methodology (RSM) based on central composite design (CCD) was applied for investigation of the effects of ultrasonic waves, temperature and solvent concentration on viscosity reduction of residue fuel oil (RFO). Ultrasonic irradiation was employed at low frequency of 24 kHz and power of 280 W. The results showed that the combination of ultrasonic waves and solven...
[ 8 ] - Propionic acid extraction in a microfluidic system: simultaneous effects of channel diameter and fluid flow rate on the flow regime and mass transfer
In this work, extraction of propionic acid from the aqueous phase to the organic phase (1-octanol) was performed in T-junction microchannels and effects of channel diameter and fluid flow rate on the mass transfer characteristics were investigated. The two-phase flow patterns in studied microchannels with 0.4 and 0.8 mm diameters were observed. Weber number and surface-to-volume ratio were ca...
[ 9 ] - Microfluidic extraction of tannic acid from Quercus leaves
In this study, extraction of tannic acid using microchannel was investigated. Affective parameters were optimized. Different solvents including buthanol, ethylacetate and n-hexane as organic phase, methanol, propanol, ethanol and water as aqueous phase investigated. Microchannels with different confluence angles and diameters were examined. Microchannels with different confluence angles and dia...
[ 10 ] - تأثیر نسبت پرشدن بر عملکرد و ضریب انتقال حرارت در تبخیرکننده و چگالنده ترموسیفون (لوله گرمایی بدون فتیله)
ترموسیفون، به دلیل ویژگی�های منحصربه فرد، جایگاه ویژه�ای در سیستم�های بهینه�سازی مصرف و بازیافت انرژی یافته �است. این مقاله، به بررسی تأثیر نسبت پرشدن، بر ضریب انتقال حرارت بخش های تبخیرکننده و چگالنده و همچنین عملکرد کلی ترموسیفون می پردازد. بدین منظور یک نمونه آزمایشگاهی ترموسیفون، از جنس مس به قطر داخلی mm5/17 و قطر خارجی mm19 و طول m1 طراحی و ساخته شد. طول بخش�های تبخیرکننده، بی�دررو و چگال...
[ 11 ] - Numerical Modeling and Simulation of Highly Preheated and Diluted Air Combustion Furnaces
This paper presents some of the results of the modeling and simulation of an industrial furnace under the conventional combustion as well as under the highly preheated and diluted air combustion (HPDAC) conditions. The results are obtained using a computer program written by authors in FORTRAN language. It was found that, the HPDAC offers a more uniform and relatively moderate gas temperature p...
[ 12 ] - Cooling Enhancement of a Photovoltaic Panel Through Ferrofluid Stimulation Using a Magnetic-Wind Turbine
Wind energy is used to rotate a magnetic turbine in order to remove heat from the surface of a photovoltaic (PV) panel. A three-bladed turbine, which rotates with wind energy, has rotational motion underneath the studied PV panel in order to move Magnetic Nano-Particles (MNPs). In addition, effects of the magnetic field strength (B=450-830 mT), rotational velocity of the magnetic turbine (ω), a...
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