Rapid industrialization and progress in the standard of living lead the world countries to an increasing consumption of energy. Since significant part of energy demand in the world is supplied by fossil fuels, depletion of fossil fuel resources and increasing pollutants formation are the main consequences of this modernization. Hence, scientific research on clean combustion technologies as well as renewable and sustainable energy resources has intensified to cope with resource scarcity and global warming issues. Combustion is a key element of many modern society’s critical technologies. Electric power generation, home heating, ground transportation, spacecraft and aircraft propulsion, and materials processing all use combustion to convert chemical energy to thermal energy or propulsive force.
The goal of Combustion and Sustainable Energy Laboratory (ComSEL) is to address scientific challenges of Energy Conversion and its Environmental impacts. Issues such as combustion systems modifications for reduction of pollutants (NOx, CO2, etc), improvements of combustion efficiencies of low calorific fuels, hybrid energy generation systems such as hybrid hydrogen production from renewable sources, or hybrid solar combustion system are hot areas of research in which combustion plays a key role.
Research in ComSEL includes both experimental and numerical investigations. In numerical studies various energy conversion systems as well as combustion technologies are modeled and optimized. In experimental investigations, the focus is to understand underlying physical and chemical processes as well as design and fabrication of energy and combustion systems.
Mechanical Engineering
Corley Hall
1811 N Boulder Avenue
Russellville, AR 72801
Phone: (479) 964-0877
Email: shosseini@atu.edu
Combustion and Sustainable Energy Laboratory (ComSEL) conducts research in the area of Renewable and Sustainable Energy and computational and experimental combustion field. Most current research involves hydrogen production, energy generation from alternative fuels (such as biogas), small-scale combustion system (meso-scale combustion) and clean combustion technology (flameless combustion) in power plants. Other research areas include application of Phase Change Material (PCM) in solar energy and refrigeration system, gas turbine systems and solar energy.
Our Vision: Promote the use of alternative fuels in clean power generation systems and transportation and using renewable and sustainable energy resources to supply environmentally-friendly power.
Mission Statement: Lead in the discovery, innovation, and advancement of science and technology for improvement of our way of life.
Current Research Projects: The lab has active research projects in the following areas:
Hydrogen Fuel Cell Drone
Hydrogen Fuel Cell Car
ATU Quadcopter
Flameless Combustion
Recently, flameless combustion has been developed widely due to extremely low pollutant
formation and fuel consumption reduction in flameless mode. However, investigation
about combustion stability is still the most important issue in flameless combustion
systems. In most past efforts, attempts have been made to increase burned-gas internal
recirculation ratio (Kv) to achieve stable flameless combustion and minimize pollutant
formation rates (especially, NOx formation). The Kv parameter is defined as the ratio
of mass flow rate of burned gases to that of the reactant previous to combustion.
In this regard, co-axial counter-flow configuration for flameless combustion has been
studied numerically and experimentally. It was found that the stability of flameless
combustion can be enhanced in this configuration.
The objective of this study is to fundamentally investigate the effects of burner air and fuel inlet configuration on the stability of flameless combustion and the rates of pollutant formation. In this newly proposed design, fuel is injected axially from one end of the cylindrical-shaped combustion chamber and air is introduced tangentially (imparting air swirl) from the other end of the chamber. Effects of air swirl being considered here has not been previously investigated but is expected to enhance performance. Exhaust gases exit the combustor from the same end where the air is introduced.
(1) (2) (3)
(1) Conventional Combustion (Flame mode)
(2)Transition from flame mode to flameless combustion
(3) Flameless mode
Experimental Investigation on Flameless Combustion
The miniaturization of small-size power supply appliances with high energy density is becoming an important issue all around the world. This is because of the fast development of Micro Electro Mechanical Systems (MEMS) during the previous decades. Small-scale combustion has great potential to be employed in many small-volume systems to supply energy demands such as power supplies for portable devices as well as propulsion units in small spacecrafts. Due to the large energy densities of hydrocarbons (~50 MJ/kg), small-scale combustion-based power generation is competitive with lithium batteries (~0.6 MJ/kg), even when the overall efficiency is around 10%. However, the reduction of combustor size has encountered some challenges. In small-scale combustion systems, due to small size of combustor some issues such as thermal management, fluid mixing, residence time and flame quenching become more important. In non-premixed meso-scale combustion systems the rate of heat loss from combustor’s wall raises because of increment in surface-to-volume ratio and hence less enthalpy is preserved in the combustion products. Moreover, since in small-scale systems the flow residence time becomes less than the combined mixing and chemical times, flame stability will be a crucial challenge. To overcome flame quenching issue in meso-scale combustors, the concept of excess enthalpy has been developed to redirect hot burned gases to preheat cold reactants (without mass exchange) to make a stable flame. However, excess enthalpy designs suffer from complexity.
Therefore, in this work, experimental investigation on meso-scale non-premixed vortex combustion systems with thermal recuperation is suggested to stabilize gaseous flames in small scale combustor for use in power generation in micro-electro-mechanic systems (MEMS) and propulsion systems. The proposed system is based on non-premixed asymmetric-swirl combustion concept which has shown stability characteristics for small-scale combustors. It is expected that the results of this proposal will substantially improve combustion stability in meso-scale combustors. This will also contribute towards the performance of small-scale propulsion units. It is expected that the flame stability region to increase due to fully tangential inlet air which creates a strong vortex flow. Moreover, the vortex flame in the reaction zone has a toroidal structure resulting from the interaction between the axial fuel jet and strong forced air vortex. Therefore, even though the fuel and air are non-premixed at the combustor, the reaction zone of asymmetric vortex flame shows premix combustion features, particularly regarding the flame color and brightness. Indeed, it is anticipated that the flow in the asymmetric vortex combustor to demonstrate recirculation phenomena. A central recirculation zone could be in the core of the combustor, and two other recirculation zones were found in the in the asymmetric region. A strong azimuthal velocity component, created by the negative pressure, is formed in the central recirculation zone. A strong swirl flow will be ensured when the inlet air velocity is very high.
Fig1. Experimental Setup
Fig2. Photographs of flame with 80 mg/s at various equivalence ratios (ϕ) (a) with thermal recuperator (b) without thermal recuperator
This study is focused on the application of phase change materials (PCM) in low temperature systems, and the influence of using PCM in a domestic refrigerator. A type of eutectic PCM solution is added to the inner compartment walls of a household refrigerator by using commercially available PCM filled containers. Water is also used as a PCM and is added to the surface of the evaporator. The system is tested to determine the effects the PCMs have on the system. The effects of PCM on the refrigeration system are investigated by comparing the On-Off cycling of the system, total run time, and energy consumption with and without PCM. The benefit of PCM in the case of power outages is also investigated. The analysis of the results illustrates a significant improvement of the performance compared to a conventional refrigeration system.
Three different cases were tested for a time period of about 1,000 minutes.
Case 1 : Empty operation (no PCM was applied)
Case 2: 0.5 kg of water applied to the surface of the evaporator.
Case 3 : 2.5 kg of eutectic material applied to walls of compartment section.
Inside refrigerator temperature and electricity usage were monitored for each case.
Dr. Ehsan Hosseini
Associate Professor
Mechanical Engineering
Corley Hall
1811 N Boulder Avenue
Russellville, AR 72801
Phone: (479) 964-0877
Email: shosseini@atu.edu
Profiles: Google Scholar
Dr. Hosseini is an Associate Professor in the Department of Mechanical Engineering at Arkansas Tech University (ATU) since August 2017. He established Combustion and Sustainable Energy Laboratory (ComSEL) at ATU working on several projects such as Solar-to-Hydrogen, Hydrogen production using hybrid concentrated photovoltaic thermal (CPVT) system integrated with Organic Rankine Cycle (ORC), Using Flameless combustion in gas turbine system, Thermal recuperation in small-scale combustion system, and application of Phase Change Material (PCM) in the refrigeration and electronic systems. Before joining Arkansas Tech University, Dr. Hosseini was a postdoctoral researcher fellow in Combustion and Solar Energy Laboratory with the Department of Mechanical Engineering at San Diego State University (SDSU) working on a hybrid solar thermal energy generation system funded by Department of Energy (DOE). He received the Ph.D. and M.Sc. degrees in mechanical engineering in 2016 and 2012, respectively. His research interests clean combustion technologies, flameless combustion, micro/meso scale combustion, propulsion, detonation, alternative fuels, renewable and sustainable energy, hybrid energy systems and optimization. Dr. Hosseini has published more than 95 scientific papers in the energy and thermofluids fields in high ranked international journals. He has more than eight years work experience in energy systems industry.
We gratefully acknowledge funding from our sponsors.
2023 “Machine Learning in Interdisciplinary Research: Space Exploration Benefits from Artificial Intelligent (AI) Solutions” NASA ($25,000), Seyed Ehsan Hosseini (PI), Azin Sanjari Pirmahaleh (Co-PI)
2023 “The performance of a hybrid photovoltaic-thermoelectric generator (PV-TEG) in comparison to a solar PV system” NASA ($25,000), Zahra Zamanipour (PI), Seyed Ehsan Hosseini (Co-PI)
2022 “Hydrogen Fuel Cell Powered Quadcopter” NASA ($25,000), Seyed Ehsan Hosseini (PI)
2021 “Control System of a Hydrogen Fuel Cell Powered Hexacopter” NASA ($10,000), Seyed Ehsan Hosseini (PI)
2020 “Fundamental Study of Hydrogen Fuel Cell Powered Systems in the Aviation and Aerospace with Special Focus on Small Unmanned Aircraft” NASA ($40,000), Seyed Ehsan Hosseini (PI), John Krohn, Aboozar Mosleh.
2019 “Experimental Investigation and Optimization of a Hydrogen Fuel Cell Engine in a Lightweight Vehicle Aligns with Clean Transportation Strategy”, Department of Transportation ($63,648), Seyed Ehsan Hosseini (PI), John Krohn.
2019 “Combustion-driven Micro-electricity Generation Using Thermoelectric System” ATU Interdisciplinary Research Center ($6,000), Seyed Ehsan Hosseini (PI), Charles Mebi, Hamed Shojaei, Reza J Hamidi.
2019 “Combustion-based Small-scale Micro-power Generation” ATU Professional Development Grant ($1,950), Seyed Ehsan Hosseini (PI).
2019 “Application of Phase Change Materials in Cooling of Electronic Devices”, NASA STEM advisor ($1,500).
2018 “Meso-scale vortex combustion with thermal recuperation system”, NASA ($35,000), Seyed Ehsan Hosseini (PI), Bruce Chahroudi, James Laylak.
2018 “Electricity consumption reduction in a refrigeration system using phase change material”, ATU Interdisciplinary Research Center ($6,000), Seyed Ehsan Hosseini (PI), Bruce Chehroudi, Mostafa Hemmati.
2018 “Experimental investigation of lab-scaled flameless combustion system with thermal recuperation”, ATU Professional Development Grant ($1,655), Seyed Ehsan Hosseini (PI).
2018 “Combustion-based small-scale power generation”, NASA Arkansas Space Grant Consortium ($2,500), Seyed Ehsan Hosseini (PI), Bruce Chehroudi.
2018 “Application of phase change material in electronic devices for cooling purposes”, NASA STEM advisor ($1,500).