Kumaran Kannaiyan

Bio: Kumaran Kannaiyan is an academic researcher from Texas A&M University at Qatar. The author has contributed to research in topics: Combustion & Jet fuel. The author has an hindex of 8, co-authored 25 publications receiving 254 citations. Previous affiliations of Kumaran Kannaiyan include Technion – Israel Institute of Technology & Texas A&M University.

Theoretical Prediction of Laminar Burning Speed and Ignition Delay Time of Gas-to-Liquid Fuel

Abstract: Gas-to-liquid (GTL), an alternative synthetic jet fuel derived from natural gas through Fischer–Tropsch (F–T) process, has gained significant attention due to its cleaner combustion characteristics when compared to conventional counterparts. The effect of chemical composition on key performance aspects such as ignition delay, laminar burning speed, and emission characteristics has been experimentally studied. However, the development of chemical mechanism to predict those parameters for GTL fuel is still in its early stage. The GTL aviation fuel from Syntroleum Corporation, S-8, is used in this study. For theoretical predictions, a mixture of 32% iso-octane, 25% n-decane, and 43% n-dodecane by volume is considered as the surrogate for S-8 fuel. In this work, a detailed kinetics model (DKM) has been developed based on the chemical mechanisms reported for the GTL fuel. The DKM is employed in a constant internal energy and constant volume reactor to predict the ignition delay times for GTL over a wide range of temperatures, pressures, and equivalence ratios. The ignition delay times predicted using DKM are validated with those reported in the literature. Furthermore, the steady onedimensional premixed flame code from CANTERA is used in conjunction with the chemical mechanisms to predict the laminar burning speeds for GTL fuel over a wide range of operating conditions. Comparison of ignition delay and laminar burning speed shows that the Ranzi et al. mechanism has a better agreement with the available experimental data, and therefore is used for further evaluation in this study. [DOI: 10.1115/1.4033984]

Effect of Carbon Dioxide on the Laminar Burning Speed of Propane-Air Mixtures

Abstract: This experimental research examined the effect of CO2 as a diluent on the laminar burning speed of propane–air mixtures. Combustion took place at various CO2 concentrations (0–80%), different equivalence ratios (0.7<ϕ<1.2) and over a range of temperatures (298–420 K) and pressures (0.5–6.2 atm). The experiments were performed in a cylindrical constant volume chamber with a Z-shaped Schlieren system, coupled with a high-speed CMOS camera to capture the propagation of the flames at speeds up to 4000 frames per second. The flame stability of these mixtures at different pressures, equivalence ratios, and CO2 concentrations was also studied. Only laminar, spherical, and smooth flames were considered in measuring laminar burning speed. Pressure rise data as a function of time during the flame propagation were the primary input of the multishell thermodynamic model for measuring the laminar burning speed of propane-CO2-air mixtures. The laminar burning speed of such blends was observed to decrease with the addition of CO2 and to increase with the gas temperature. It was also noted that the laminar burning speed decreases with increasing pressure. The collected experimental data were compared with simulation data obtained via a steady one-dimensional (1D) laminar premixed flame code from Cantera, using a detailed H2/CO/C1–C4 kinetics model encompassing 111 species and 784 reactions.

Theory of cross-correlation analysis of PIV images : Image analysis as measuring technique in flows

Abstract: To improve the performance of particle image velocimetry in measuring instantaneous velocity fields, direct cross-correlation of image fields can be used in place of auto-correlation methods of interrogation of double- or multiple-exposure recordings. With improved speed of photographic recording and increased resolution of video array detectors, cross-correlation methods of interrogation of successive single-exposure frames can be used to measure the separation of pairs of particle images between successive frames. By knowing the extent of image shifting used in a multiple-exposure and by a priori knowledge of the mean flow-field, the cross-correlation of different sized interrogation spots with known separation can be optimized in terms of spatial resolution, detection rate, accuracy and reliability.

A Benchmark Study on the Thermal Conductivity of Nanofluids

Abstract: This article reports on the International Nanofluid Property Benchmark Exercise, or INPBE, in which the thermal conductivity of identical samples of colloidally stable dispersions of nanoparticles or “nanofluids,” was measured by over 30 organizations worldwide, using a variety of experimental approaches, including the transient hot wire method, steady-state methods, and optical methods. The nanofluids tested in the exercise were comprised of aqueous and nonaqueous basefluids, metal and metal oxide particles, near-spherical and elongated particles, at low and high particle concentrations. The data analysis reveals that the data from most organizations lie within a relatively narrow band (±10% or less) about the sample average with only few outliers. The thermal conductivity of the nanofluids was found to increase with particle concentration and aspect ratio, as expected from classical theory. There are (small) systematic differences in the absolute values of the nanofluid thermal conductivity among the various experimental approaches; however, such differences tend to disappear when the data are normalized to the measured thermal conductivity of the basefluid. The effective medium theory developed for dispersed particles by Maxwell in 1881 and recently generalized by Nan et al. [J. Appl. Phys. 81, 6692 (1997)], was found to be in good agreement with the experimental data, suggesting that no anomalous enhancement of thermal conductivity was achieved in the nanofluids tested in this exercise.

Recent development in studies of alternative jet fuel combustion: Progress, challenges, and opportunities

Abstract: With the growing air transport demand and concerns about its environmental impacts, alternative jet fuels derived from non-conventional sources have become an important strategy for achieving a sustainable and green aviation. In the past 10 years, governments around the world along with aviation industry have invested significant efforts into exploring all sorts of alternative jet fuels that can be used to power aircraft engines. Among all the alternative jet fuels explored, the aviation sector has agreed that hydrocarbon-based ‘drop-in’ replacement fuels, which are fully interchangeable and compatible with current conventional jet fuels, would be the best choice in the near future, as they can be used without any modifications to today׳s aircraft or fuel infrastructure. This paper reviews the current state of development of ‘drop-in’ alternative jet fuels including various Fisher–Tropsch synthetic jet fuels and bio-jet fuels. Recent advances in research activities on alternative jet fuels, including fuel property evaluations, combustor component tests, engine tests, and flight tests, are highlighted. Furthermore, basic research needs for understanding the combustion characteristics of alternative jet fuels are underlined and discussed by reviewing recent fundamental combustion studies on ignition, extinction, flame propagation, emissions, and species evolution of various conventional and alternative jet fuels. Recognizing that the use of ‘simpler’ surrogate fuels to emulate the behavior of ‘complex’ alternative jet fuels is of fundamental and practical importance for the development of physics-based models to enable quantitative emissions and performance predictions using combustion modeling, recent studies on surrogate formulation for alternative jet fuels are also reviewed and discussed. This review concludes with a brief discussion of future research directions.

A review of carbon capture and utilisation as a CO2 abatement opportunity within the EWF nexus

Abstract: Carbon capture and utilisation (CCU) is considered an important CO2 mitigation strategy to support and compliment carbon capture and storage (CCS) objectives for the abatement and sequestration of CO2. It represents various pathways that utilise CO2 as a feedstock in process systems or otherwise for the generation of value-added commodities. The CO2 used can be captured from different sources including power plants and industrial activities via several existing carbon capture and separation technologies that ensure a pure and safe CO2 supply. CCU pathways are mainly divided into five wide-ranging categories: CO2 conversion to chemicals and fuels, mineral carbonation, enhanced oil recovery, biological conversion, and direct CO2 utilisation. This study reviews the main CCU pathways and highlights their intra-sectoral and inter-sectoral opportunities within the energy water and food (EWF) systems, which is an important resource management concept. It also discusses the global status of CCU operational projects, research and development efforts directed toward CCU deployment, and important decision-making directions when integrating CCU with the EWF nexus. This review highlights that CCU pathways provide several cross-sectoral opportunities within the EWF sectors, by allaying resource competition between sectors and proposing co/tri-integrated solutions for securing EWF resources. Future efforts in this regard should be directed towards studying the EWF nexus within CCU routes in a comprehensive, quantitative, and holistic approach to identify and measure all trade-offs and synergies within EWF sectors, and to optimise CCU supply chains.