Fa
  • Ph.D. (1996)

    mechanical engineering

    , Russia, Russia

  • M.Sc. (1990)

    mechanical engineering

    , Tarbiat Modares University,

  • B.Sc. (1984)

    mechanical engineering

    , Iran University of Science and Technology,

  • Engine, propulsion and turbo-machines
  • Thermodynamics and environment
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Curriculum Vitae (CV)

Performance of a multi-stage thermoacoustically-driven pulse tube cryocooler: Uncertainty quantification and sensitivity analysis

M Bahrami, F Ommi
Journal Paper , , {Pages }

Abstract

Experimental Study of the Effect of a Non-Oxygenated Additive on Spark-Ignition Engine Performance and Pollutant Emissions

S Davari, F Ommi, Z Saboohi, M Safar
Journal PaperInternational Journal of Engineering , Volume 34 , Issue 4, 2021 April 1, {Pages 1035-1045 }

Abstract

In this study, effects of adding butene, homopolymer to gasoline on the performance of a four-stroke spark ignition (SI) engine and pollutant emissions have been investigated. This additive increases the octane number of gasoline. In this research, the additive was combined with a non-leaded gasoline. Also, in addition to fuel changes and the use of additives, engine spark plugs were replaced and three types of spark plugs were used for this study. These include single electrode spark plug, dual electrode spark plug and Platinum+ 4 spark plug. The results of experimental tests showed that with the addition of additive to gasoline, the brake torque and braking power were increased with the use of each of the three spark plug type. The result

Study of the effect of bluff body size on stability limits of a premixed natural gas swirl burner

Milad Behzadi, Seyed Hamzeh Siyadat, Fathollah Ommi, Zoheir Saboohi
Journal PaperJournal of Thermal Analysis and Calorimetry , 2021 February 5, {Pages 14-Jan }

Abstract

Flame stabilization is highly important in lean premixed combustion which is considered a desirable technology for low-emission gas turbines. Swirl stabilization is one of the most common methods used for this purpose. Simple generation of swirl, however, is not enough to reach an acceptable operating range. A method of improving stability is using a bluff body in order to resist flame flashback caused by combustion-induced vortex breakdown at moderate to high swirl numbers. The present study aims to investigate the effect of bluff body size on the stability boundaries of flashback and blowout and also on flame shape. A premixed swirl burner is designed and built to operate with natural gas at atmospheric condition. In addition to gas and a

Experimental study of the effects of multi-electrode spark plugs to improve engine performance and reduce pollutants of the XU7JP/L3 engine

Meysam Safar, Fathallah Ommi, Zahir Saboohi
Journal Paper , Volume 50 , Issue 493001046, 2021 January 20, {Pages 105-113 }

Abstract

In this study, the effects of using multi-electrode spark plugs on the performance parameters of an internal combustion engine were investigated using experimental tests. In this regard, experimental tests have been carried out using two types of lead-free gasoline, as well as a combination of gasoline with commercial additive (Keropur-G). The results of experimental tests show that with the use of multi-electrode spark plugs in conventional fuel and fuel with additive, the braking torque and braking power are increased and in comparison the specific fuel consumption (SFC) is decreased. Also the use of multi-electrode spark plugs increases the emission of nitrogen oxides and reduces the emissions of unburnt hydrocarbons, carbon monoxide and

A new synthetic metamodel methodology for liquid‐propellant engine's cooling system optimization

Hamid Reza Alimohammadi, Hassan Naseh, Fathollah Ommi
Journal PaperHeat Transfer , Volume 50 , Issue 1, 2021 January , {Pages 907-941 }

Abstract

The present paper strives for optimization of the cooling system of a liquid‐propellant engine (LPE). To this end, the new synthetic metamodel methodology utilizing the design of experiment method and the response surface method was developed and implemented as two effective means of designing, analyzing, and optimizing. The input variables, constraints, objective functions, and their surfaces were identified. Hence, the design and development strategy of combustion chamber and nozzle was clarified, and 64 different experiments were carried out on the RD‐161 propulsion system, of which 47 experiments were approved and compatible with the problem constraints. This engine used all three modes of cooling: the radiation cooling, the regene

Experimental and numerical study of a twin-fluid two-phase internal-mixing atomizer

Alireza Mohammadi, Fathollah Ommi, Zoheir Saboohi
Journal PaperJournal of Thermal Analysis and Calorimetry , 2021 April 26, {Pages 15-Jan }

Abstract

This paper presents a numerical, and experimental study on atomization characteristics and droplet distribution of a twin-fluid two-phase internal mixing atomizer. Using the discrete phase model and Eulerian–Lagrangian numerical study, internal and external flow fields are simulated to describe two-phase flow in mixing chamber. The exterior region near the exit nozzle in the combustion chamber is simulated by particle trajectory method. Internal-mixing atomizer is manufactured and tests are carried out to verify the numerical results by applying shadowgraph method visualizing flow near the exit nozzle of the atomizer and downstream in combustion chamber. In order to study atomization characteristics including droplet dimension and velocit

Numerical simulation of a solar air heater equipped with wavy and raccoon-shaped fins: The effect of fins’ height

Ebrahim Rahmani, Tofigh Moradi, Abolfazl Fattahi, Mostafa Delpisheh, Nader Karimi, Fathollah Ommi, Zoheir Saboohi
Journal PaperSustainable Energy Technologies and Assessments , 2021 April 15, {Pages 101227 }

Abstract

Increasing electricity demand in the world’s energy profile and the focus on carbon footprint reduction motivates countries to utilize renewable sources of energy, such as solar. This has elicited in development of solar air heaters, as a simple solar energy extraction device, academically and practically. Many efforts have been made to upgrade thermally solar air heaters using passive and active remedies. Many types of inserts have been examined; however, the effects of sinusoidal fins are rarely investigated. Therefore, a numerical simulation is implemented to evaluate fins in wavy and raccoon configurations. The effect of fins’ height (25% and 50% of the channel’s height) and the Reynolds number of the turbulent flow (12000 and 240

Developing a Multi-objective Multi-Disciplinary Robust Design Optimization Framework

MNP Meibody, H Naseh, F Ommi
Journal PaperScientia Iranica , 2021 March 10, {Pages }

Abstract

The purpose of this study is to provide an efficient Multi-Objective Multidisciplinary Robust Design Optimization (MOMRDO) framework. To this end, Bi-Level Integrated System Synthesis (BLISS) framework is implemented as a fast Multi-disciplinary Design Optimization (MDO) framework. Progressive Latin Hypercube Sampling (PLHS) is developed as a Design of Experiment (DOE) of the Uncertainty Analysis (UA). This systematic approach leads to a fast, adaptive and efficient framework for Robust Design Optimization (RDO) of complex systems. The accuracy and performance of the proposed algorithm have been evaluated with various tests. Finally, the RDO of a hydrazine monopropellant thruster is defined as a case study. The results show that the propose

Comparison of waste heat recovery from a Proton Exchange Membrane fuel cell by gas turbine or Organic Rankin Cycle: a display of 3E analysis

V Mohammadzadeh, F Ommi, Z Saboohi, E Gholamian
Journal Paper , , {Pages }

Abstract

Comparison of waste heat recovery from Proton Exchange Membrane fuel cell by gas turbine or Organic Rankin Cycle: a manifestation of 3E analysis

V Mohammadzadeh, F Ommi, Z Saboohi, E Gholamian
Journal Paper , , {Pages }

Abstract

Developing an augmented onset model for a thermoacoustically-driven, pulse tube cryocooler

M Bahrami, F Ommi
Journal Paper , , {Pages }

Abstract

Multi-objective optimization of a lean premixed laboratory combustor through CFD-CRN approach

H Khodayari, F Ommi, Z Saboohi
Journal Paper , , {Pages }

Abstract

Two-dimensional numerical simulation of pyrolysis and erosion in a solid rocket motor diverging-converging nozzle

M Razmjooei, M Shahbazi, F Ommi
Journal Paper , , {Pages }

Abstract

Numerical study of different flame regimes in the laminar counterflow spray

M Havasi, F Ommi, F Chitgarha
Journal Paper , , {Pages }

Abstract

Identification of the Droplet Group Combustion Formation Region by the Flame Index Parameter in the Laminar Counterflow Spray

M Havasi, F Ommi, F Chitgarha, Z Saboohi
Journal Paper , , {Pages }

Abstract

Uncertainty Analysis of the Chemical Reactor Network Approach for Predicting the Pollutant Emissions in a Double Swirl Combustor

Hamidreza Khodayari, Fathollah Ommi, Zoheir Saboohi
Journal PaperJournal of Energy Resources Technology , 2020 February 26, {Pages 22-Jan }

Abstract

The purpose of this study is to predict the pollutant emissions generated within an aero-engine combustor model using the computational fluid dynamics-chemical reactor network (CFD-CRN) approach by modeling combustion in highly swirled flows. The selected test case is a laboratory double swirled combustor for CH4/Air diffusion flames at atmospheric pressure. The numerically achieved time-averaged values of the velocity components are in good agreement with the experimental data for two different thermal power. The CRN is obtained by dividing the flow field into ideal chemical reactors using various filters on the CFD results. The temperature, axial velocity, CH4, and O2 mass fractions distributions are selected as the splitting criteria for

Large eddy simulation of the destruction of convecting hot fluid pockets through a cold channel flow

Z Saboohi, F Ommi, A Fattahi, N Karimi
Journal PaperInternational Journal of Thermal Sciences , Volume 156 , 2020 October 1, {Pages 106475 }

Abstract

Hot fluid pockets or hot spots can be found in many engineering systems, such as chemical reactors, internal heat engines and gas turbines. They are inherently fluid parcels with rapid temperature rising in comparison with the base medium and usually convect with the flow inertia. Due to the higher energy content, hot fluid pockets can change thermal characteristics of the system. Ignoring the destruction of them, which has been mainly missed in the literature, can therefore change the related predictions. The destruction of the hot fluid pockets is so investigated in this paper using a large eddy simulation and some statistical indices are used to reveal the coherence of the pockets. The results show that the convecting hot pocket can be s

Comparison of gas turbine inlet air cooling systems for several climates in Iran using energy, exergy, economic, and environmental (4E) analyses

Mohammad Reza Majdi Yazdi, Fathollah Ommi, MA Ehyaei, Marc A Rosen
Journal PaperEnergy Conversion and Management , Volume 216 , 2020 July 15, {Pages 112944 }

Abstract

The effects are investigated of using absorption chiller, heat pump, and inlet fogging systems for cooling the inlet air of a gas turbine power plant for four cities in Iran representative of different climatic conditions, namely Yazd (hot–arid), Bandar Abbas (hot–humid), Ardabil (cold-humid) and Sari (humid subtropical). Gas turbine functional parameters, quantities of emitted pollutants, prices of generated electricity and capital cost payback periods are determined. The rates of pollutants produced and fuel consumption are considered per unit of electricity generated. The results show that the best cooling system for cities with hot climates is the absorption chiller; it improves gas turbine net power by 18% in Bandar Abbas and 14% i

A review on the applications of the chemical reactor network approach on the prediction of pollutant emissions

Hamidreza Khodayari, Fathollah Ommi, Zoheir Saboohi
Journal PaperAircraft Engineering and Aerospace Technology , 2020 March 12, {Pages }

Abstract

PurposeThe purpose of this paper is to review the applications of the chemical reactor network (CRN) approach for modeling the combustion in gas turbine combustors and classify the CRN construction methods that have been frequently used by researchers.Design/methodology/approachThis paper initiates with introducing the CRN approach as a practical tool for precisely predicting the species concentrations in the combustion process with lower computational costs. The structure of the CRN and its elements as the ideal reactors are reviewed in recent studies. Flow field modeling has been identified as the most important input for constructing the CRNs; thus, the flow field modeling methods have been extensively reviewed in previous studies. Netwo

Uncertainty Analysis of the Chemical Reactor Network Approach for Predicting the Pollutant Emissions in a Double-Swirl Combustor

Hamidreza Khodayari, Fathollah Ommi, Zoheir Saboohi
Journal PaperJournal of Energy Resources Technology , Volume 142 , Issue 9, 2020 September 1, {Pages }

Abstract

The purpose of this study is to predict the pollutant emissions generated within an aero-engine combustor model using the computational fluid dynamics-chemical reactor network (CFD-CRN) approach by modeling combustion in highly swirled flows. The selected test case is a laboratory double swirled combustor that came with an extensive experimental database from previous works for CH4/air diffusion flames at atmospheric pressure. The CFD-CRN modeling approach is initiated by solving Reynolds-averaged Navier–Stokes (RANS) equations for a 3D computational domain. The numerically achieved time-averaged values of the velocity components are in good agreement with the experimental data for two different thermal power. The CRN is obtained by divid

Current Teaching

  • Ph.D.

    Advanced Internal Combustion Engines

  • Ph.D.

    Selected Topics in Propulsion

Teaching History

  • Ph.D.

    Fundamentals of Propulsion

  • Ph.D.

    Spray Combustion

  • 2017
    Babamoradi, Mohsen
    Cross injection in supersonic flow test room equipment design, manufacture and test to investigate the stability of operating fluid in spraying to combustion chamber
  • 2018
    Ansari, Amirhosein
  • 2018
    Saadatjoo, Morteza
  • 2018
    Azizzadeh Araey, Ali
  • 2016
    Jafari Panah, Saeid
    Investigation of pergormance improvement of turbofan engine by aerodynamic optimization of high-pressure turbine and evalution og engine performance in off-design conditionsInvestigation of pergormance improvement of turbofan engine by aerodynamic optimiz
  • 2018
    Farokhinejad, Mehrdad
  • 2018
    Yadegari, Mehdi

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