Amirhossein Azimi

Aerospace and Mechanical Engineer

About Me

     Hello. My name is Amirhossein and I am an aerospace and mechanical engineer interested in research on the advancement of science and technology. Throughout my studies, I have acquired many skills and experiences that allow me to participate in investigations on thermofluids with a vast realm of applications. During the past five years, I have been working on the development of combustion test facilities, leading to the emergence of clean and efficient combustion methodologies. Among these techniques was the development of MILD combustion technology for liquid fuels, which has numerous applications in the respective industry.

     I am genuinely interested in the advancement of new combustion systems for clean, efficient, and stable combustion. I have a predilection for internal combustion engines, such as gas turbines and reciprocating engines, as well as other combustion systems such as furnaces and boilers. Besides, I am interested in the design of heating, ventilation, air-conditioning, and refrigeration systems, as well. Please take a moment to explore my website, where you will find some information about my background and my areas of expertise. For more details, you may view my CV.

Experience

Oct. 2016 - Apr. 2019

R.A. at Sharif University Aerospace Advanced Combustion Lab. (AACL)

  • Designed and constructed a laboratory-scale test rig to investigate the combustion of liquid fuels under hot-diluted conditions
  • Developed an image processing code for analysis of flame photographs                                            [View Documents]
Feb. 2015 - Sep. 2016
  • Participated in the design and construction of a gas turbine combustor test rig
  • Participated in the testing of a sample gas turbine combustor for performance optimization
  • Developed a numerical code for heat transfer analysis of gas turbine combustors                                 [View Documents]

Education

Sep. 2016 - Jan. 2019

M.Sc. in Aerospace Engineering

Sharif University of Technology, Tehran, Iran

Cum. GPA: 3.89/4.0 [View Transcript]

Thesis Title: “Experimental and Numerical Investigation of Spray Flame under Hot-Diluted Conditions” 

Sep. 2011 - Aug. 2016

B.Sc. in Mechanical Engineering

Amirkabir University of Technology (Tehran Polytechnic)

Cum. GPA: 3.76/4.0 [View Transcript]

Sep. 2011 - Apr. 2016

B.Sc. in Aerospace Engineering

Amirkabir University of Technology (Tehran Polytechnic)

Cum. GPA: 3.89/4.0 [View Transcript]

Thesis Title: “Design and Construction of an Atmospheric Gas Turbine Combustor Test Rig ” 

Expertise

Experimental Combustion Investigation 90%
Design and Construction of Test Facilities 90%
Project Management, Team Work, Technical Report Writing 85%
Measurement Techniques and Data Analysis 90%
Numerical Simulation of Reactive Flows 70%
Heat Transfer Analysis of Combustors and Coolig Techniques 85%
HVAC and Refrigeration Sys. Design 60%
SolidWorks | AutoCAD 65%
ANSYS Fluent, Gambit, ICEM; TecPlot360 70%
Fortran 95, MATLAB 60%

Interests

Experimental Research on Reactive Flows 100%
Numerical Simulation of Multiphase Reactive Flows 90%
Design and Construction of Combustion Systems 95%
Turbulent Combustion of Liquid and Gaseous Fuels 90%
Heat Transfer Analysis of Combustors 80%
Thermo-Acoustic Coupling 80%

English Proficiency

TOEFL iBT Score: 109/120

Reading
Listening
Speaking
Writing

Honors and Awards

  • 2018

    Select M.S. Thesis of the year in Aerospace Department of Sharif University of Technology

  • 2017

    19th Khwarizmi Youth Award for Design and Construction of Gas Turbine Combustor Test Rig

  • 2016

    Awarded Sharif University of Technology Fellowship for M.S.

  • 2016

    Selected for graduate studies without the National University Entrance Exam (Konkoor) at Sharif University of Technology

  • 2015

    Ranked 3rd out of 67 students of Aerospace Department, Amirkabir University of Technology, Class of 2011-2015

  • 2013

    Distinguished Double Major student at Amirkabir University of Technology

  • 2011

    Awarded Amirkabir University of Technology Fellowship for B.S.

  • 2011

    Ranked as top 0.2% in the National University Entrance Exam for Undergraduate Studies (Konkoor) among more than 300,000 participants

Publications

An Experimental Study on Spray Combustion under Conventional and Hot-Diluted Conditions

     Combustion and Flame, 2020 | Co-Author: Amir Mardani

     A laboratory-scale test facility has been developed at Sharif University of Technology to investigate the combustion of a heavy liquid fuel (kerosene) spray under hot-diluted conditions, as well as conventional conditions. By examining flame photographs, chemiluminescence images, and in-field temperature measurements, the autonomous effect of different variables including oxygen concentration, temperature and velocity of the co-flowing air, fuel flow rate and injection pressure, and eventually the type of spray nozzle on the operational parameters such as flame stability, structure, luminosity, temperature distribution and CH radical concentration, as well as HCO and NO2, in the reaction region, have been studied. It was observed that an increment in injection pressure and co-flow temperature enhances the spray flame stability, while dilution exacerbates it. Also, a solid cone spray pattern with a lower spray angle has better stability as compared to hollow cone ones with higher spray angle. For combustion of spray in conventional condition, a double-flame structure was observed consisting of a bluish section at the leading edge emerging into a yellowish sooting trail. An increase in co-flow velocity, as well as injection pressure, strengthens the inner flame front, whereas raising the co-flow temperature or diluting the oxidant, deteriorates the inner flame front. In the case of highly preheated air, the flame liftoff height is reduced to as close to the atomizer as a few millimeters, forming a single flame structure, similar to gaseous flames. Combined effects of preheating and dilution alter the spray flame structure in a way that the reaction volume is reduced, the temperature field has become more homogeneous, the peak temperature is limited to less than 1500k, and temperature fluctuations have significantly decreased, resembling MILD combustion regime conditions.

[To be published by Elsevier; full text is available on request]

Design and Construction of MILD-Spray Test Facility and Experimental Investigation on Kerosene Spray Flame in MILD Combustion Regime

     Fuel and Combustion, 2020 | Co-Author: Amir Mardani

     MILD (moderate or intense low oxygen dilution, also known as FLOX, CDC, and LNI) combustion is a promising technology for a clean, stable, and high-efficiency combustion. On the other hand, the combustion of liquid fuels under this combustion regime has immeasurable potentialities in industrial applications such as gas turbines, petrochemical furnaces, and steel heat treatment furnaces. Even though up to this day multiple research groups have investigated the physical and practical aspects of MILD combustion for gaseous fuels, research on liquid fuels, in particular in their most practical manner, i.e., spray, has been so scanty. In the present Work, a novel type test rig is designed and constructed at Sharif University Advanced Combustion Laboratory (AACL) to scrutinize the phenomena involving the combustion of liquid spray under hot-diluted conditions. The process of designing the underlined test rig is comprehensively presented, and the operability tests are delineated. Additionally, results of tests with kerosene spray issued in a coflow with various conditions are thoroughly discussed. Based on the experimental results, in conventional combustion, spray flame emerges a double flame structure consisting of an inner and an outer flame front. On the other hand, increasing the coflow temperature or diluting the oxidant, deteriorates the inner flame front, leading to a semi-single flame structure, similar to gaseous flames. It was also noticed that in such hot-diluted environment the reaction volume is reduced, the temperature field has become more homogeneous, the peak temperature is limited to less than 1500k, and temperature fluctuations have significantly decreased, which resembles MILD combustion regime conditions, corroborating its viability for liquid fuels. The experimental results can be used as a database to verify the capability of numerical models in simulating the underlined combustion regime, as well.

[In preparation; full text will be available by March 2020]

On the Chemiluminescence of Multiple Species in Combustion of Spray under Conventional and Hot-Diluted Conditions

     8th Iran Fuel and Combustion Conference, March 2020 | Co-Author: Amir Mardani

     CH chemiluminescence has been a technique used in the study of the flame structure of different configurations for decades. In the Present Study, a comprehensive investigation on the effects of preheating and dilution of oxidizer on the structure of kerosene spray flame is conducted by utilizing CH chemiluminescence photographs, as well as HCO and NO2 photos. To do so, a DSLR camera is equipped with three sets of optical bandpass filters, each of which coincides with the before mentioned species in the reaction region. Flame photos are analyzed by using an in-house image processing code capable of scrutinizing multiple aspects of flame such as length, width, liftoff height, and spectral analysis. Based on the experimental data, a double-flame structure, consisting of an inner and an outer flame front, was observed with a bluish, presumably premixed, section at the leading edge emerging into a yellow sooting trail. It is also observed that an increase in either airflow rate or injection pressure considerably boosts the intensity of the inner flame front due to enhancement in air entrainment toward central region. An Increase in coflow temperature alters from a double-flame to a single flame front, similar to gaseous flames. Also, liftoff height is reduced to as close to the atomizer as a few millimeters, the flame volume is contracted, and the flame luminosity is considerably heightened. On the other hand, dilution causes the flame volume to expand, reduces the flame intensity and luminosity, and undermines the inner flame front. 

[In preparation; full text will be available by March 2020] 

Effects of Preheating and Dilution on Kerosene Spray Flame Structure

     Iran’s First International Combustion School Poster Presentation (ICS2019), August 2019 | Co-Author: Amir Mardani

     To investigate the combustion of liquid fuel spray under hot-diluted conditions, a novel type rest rig was designed and constructed at Sharif University of Technology Aerospace Advanced Combustion Laboratory (AACL). By examining flame photographs, as well as CH chemiluminescence images, and in-field temperature measurements, effects of preheating (up to 733k) and dilution of the oxidant (as low as 17%O2) on kerosene spray flame structure have been studied. It was observed that, in conventional combustion, spray flame emerges a double flame structure consisting of an inner and an outer flame front. On the other hand, increasing the coflow temperature or diluting the oxidant, deteriorates the inner flame front, leading to a semi-single flame structure, similar to gaseous flames. It was also noticed that in such hot-diluted environment the reaction volume is reduced, the temperature field has become more homogeneous, the peak temperature is limited to less than 1500k, and temperature fluctuations have significantly decreased, which resembles MILD combustion regime conditions, corroborating its viability for liquid fuels.

[Download PDF]

Designing a Gas Turbine Combustor Test Rig and Testing a Sample Combustor at Atmospheric Conditions

    Fuel and Combustion, Volume 10, Issue 1, Page 87-104, 2017. (In Persian) | Co-Author: Sadegh Tabejamaat

     In this paper, the design and construction of a gas turbine combustor test rig and the experimental results of a sample combustor sector at atmospheric conditions are described. This test rig can be used to evaluate the effects of geometric variations on the performance of the combustion chamber. Flammability, stability and ignition maps, exhaust gas composition and temperature profile, and liner wall temperature can be studied. This rig has the potentiality of performing combustion tests with a maximum airflow rate of 800m3/h and preheated air up to 1000K, as well as different types of liquid or gas fuels. A single swirler sector of an annular combustor is tested at different air and fuel mass flow rates. The results show that the exhaust gas temperature has a non-linear correlation with the fuel to air ratio. Using a one-dimensional model, the exhaust temperature of the combustion chamber is predicted and compared with the experimental results. The model results show good agreement with the experimental results.

[Download PDF]

Design and Construction of an Atmospheric Gas Turbine Combustor Test Section

   6th Iran Fuel and Combustion Conference, Mashhad, Iran, February 2016, Paper No. 92. (In Persian) | Co-Author: Sadegh Tabejamaat

     In this paper, the procedure of designing a gas turbine combustion chamber test rig test section operating at atmospheric conditions is described. This test rig can be used to evaluate the effects of geometric variations on the performance of the combustion chamber, as well as determining the flammability, stability and ignition maps, exhaust gas composition and temperature profile, and liner wall temperature. This rig has the potentiality of performing combustion tests with a maximum airflow rate of 800m3/h and preheated air up to 1000K, as well as different types of liquid or gas fuels.

[Download PDF]

Dr. Amir Mardani

  • Website
  • amardani@sharif.edu
  • (+9821) 6602 2731

Prof. Sadegh Tabejamaat

Dr. Mehran Tadjfar

  • Website
  • mtadjfar@aut.ac.ir
  • (+9821) 6454 3211