Effect of Temperature, Pressure and Equivalence Ratio on Ignition Delay in Ignition Quality Tester (IQT): Diesel, n-Heptane, and iso-Octane Fuels under Low Temperature Conditions

2015 ◽  
Vol 8 (3) ◽  
pp. 537-548 ◽  
Author(s):  
Seung Yeon Yang ◽  
Nimal Naser ◽  
Suk Ho Chung ◽  
Junepyo Cha
Keyword(s):  
Low Temperature ◽  
Ignition Delay ◽  
Equivalence Ratio ◽  
Effect Of Temperature ◽  
Temperature Conditions ◽  
Ignition Quality ◽  
Ignition Quality Tester

A Proposed Biodiesel Combustion Kinetics Based on the Computational Fluid Dynamics Results in an Ignition Quality Tester

2019 ◽  
Vol 141 (8) ◽  
Author(s):  
Mahmoud Elhalwagy ◽  
Chao Zhang
Keyword(s):  
Methyl Ester ◽  
Ignition Delay ◽  
Methyl Esters ◽  
Direct Injection ◽  
Combustion Process ◽  
Major Fatty Acid ◽  
Combustion Behavior ◽  
Ignition Quality ◽  
Reaction Constants ◽  
Ignition Quality Tester

In this paper, five biodiesel global combustion decomposition steps are added to a surrogate mechanism to accurately represent the chemical kinetics of the decomposition of different levels of saturation of biodiesel, which are represented by five major fatty acid methyl esters. The reaction constants were tuned based on the results from the numerical simulations of the combustion process in an ignition quality tester (IQT) in order to obtain accurate cetane numbers. The prediction of the complete thermophysical properties of the five constituents is also carried out to accurately represent the physics of the spray and vaporization processes. The results indicated that the combustion behavior is controlled more by the spray and breakup processes for saturated biodiesel constituents than by the chemical delay, which is similar to the diesel fuel combustion behavior. The chemical delay and low temperature reactions were observed to have greater effects on the combustion and ignition delay for the cases of the unsaturated biodiesels. The comparison between the physical ignition delay and overall ignition delay between the saturated and unsaturated biodiesel constituents has also confirmed those stronger effects for the physical delay in the saturated compounds as compared to the unsaturated compounds. The validation of the proposed model is conducted for the simulations of two direct injection diesel engines using palm methyl ester and rape methyl ester.

Formulation of Sasol Isomerized Paraffinic Kerosene Surrogate Fuel for Diesel Engine Application Using an Ignition Quality Tester

2017 ◽  
Vol 139 (9) ◽  
Author(s):  
Ziliang Zheng ◽  
Tamer Badawy ◽  
Naeim Henein ◽  
Peter Schihl ◽  
Eric Sattler
Keyword(s):  
Diesel Engine ◽  
Ignition Delay ◽  
Alternative Fuels ◽  
Internal Combustion Engines ◽  
Cetane Number ◽  
Surrogate Fuels ◽  
Cycle Simulation ◽  
Ignition Quality ◽  
Surrogate Fuel ◽  
Ignition Quality Tester

Sasol isomerized paraffinic kerosene (IPK) is a coal-derived synthetic fuel under consideration as a blending stock with jet propellant 8 (JP-8) for use in military equipment. However, Sasol IPK is a low ignition quality fuel with derived cetane number (DCN) of 31. The proper use of such alternative fuels in internal combustion engines (ICEs) requires the modification in control strategies to operate engines efficiently. With computational cycle simulation coupled with surrogate fuel mechanism, the engine development process is proved to be very effective. Therefore, a methodology to formulate Sasol IPK surrogate fuels for diesel engine application using ignition quality tester (IQT) is developed. An in-house developed matlab code is used to formulate the appropriate mixture blends, also known as surrogate fuel. And aspen hysys is used to emulate the distillation curve of the surrogate fuels. The properties of the surrogate fuels are compared to those of the target Sasol IPK fuel. The DCNs of surrogate fuels are measured in the IQT and compared with the target Sasol IPK fuel at the standard condition. Furthermore, the ignition delay, combustion gas pressure, and rate of heat release (RHR) of Sasol IPK and its formulated surrogate fuels are analyzed and compared at five different charge temperatures. In addition, the apparent activation energies derived from chemical ignition delay of the surrogate fuel and Sasol IPK are determined and compared.

Experimental and Kinetic Modeling of Kerosene-Type Fuels at Gas Turbine Operating Conditions

2006 ◽  
Vol 129 (3) ◽  
pp. 655-663 ◽  
Author(s):  
P. Gokulakrishnan ◽  
G. Gaines ◽  
J. Currano ◽  
M. S. Klassen ◽  
R. J. Roby
Keyword(s):  
Low Temperature ◽  
Gas Turbine ◽  
Ignition Delay ◽  
Delay Time ◽  
Equivalence Ratio ◽  
Ignition Delay Time ◽  
Flow Reactor ◽  
Fuel Oil ◽  
Stirred Reactor ◽  
Lean Conditions

Experimental and kinetic modeling of kerosene-type fuels is reported in the present work with special emphasis on the low-temperature oxidation phenomenon relevant to gas turbine premixing conditions. Experiments were performed in an atmospheric pressure, tubular flow reactor to measure ignition delay time of kerosene (fuel–oil No. 1) in order to study the premature autoignition of liquid fuels at gas turbine premixing conditions. The experimental results indicate that the ignition delay time decreases exponentially with the equivalence ratio at fuel-lean conditions. However, for very high equivalence ratios (>2), the ignition delay time approaches an asymptotic value. Equivalence ratio fluctuations in the premixer can create conditions conducive for autoignition of fuel in the premixer, as the gas turbines generally operate under lean conditions during premixed prevaporized combustion. Ignition delay time measurements of stoichiometric fuel–oil No. 1∕air mixture at 1 atm were comparable with that of kerosene type Jet-A fuel available in the literature. A detailed kerosene mechanism with approximately 1400 reactions of 550 species is developed using a surrogate mixture of n-decane, n-propylcyclohexane, n-propylbenzene, and decene to represent the major chemical constituents of kerosene, namely n-alkanes, cyclo-alkanes, aromatics, and olefins, respectively. As the major portion of kerosene-type fuels consists of alkanes, which are relatively more reactive at low temperatures, a detailed kinetic mechanism is developed for n-decane oxidation including low temperature reaction kinetics. With the objective of achieving a more comprehensive kinetic model for n-decane, the mechanism is validated against target data for a wide range of experimental conditions available in the literature. The data include shock tube ignition delay time measurements, jet-stirred reactor reactivity profiles, and plug-flow reactor species time–history profiles. The kerosene model predictions agree fairly well with the ignition delay time measurements obtained in the present work as well as the data available in the literature for Jet A. The kerosene model was able to reproduce the low-temperature preignition reactivity profile of JP-8 obtained in a flow reactor at 12 atm. Also, the kerosene mechanism predicts the species reactivity profiles of Jet A-1 obtained in a jet-stirred reactor fairly well.

Experimental investigation of the effect of temperature on ignition of modified kerosene

2021 ◽  
pp. 146808742098819
Author(s):  
Aldin Justin Sundararaj ◽  
K R Guna ◽  
Matthew William
Keyword(s):  
Surface Tension ◽  
Gas Phase ◽  
Ignition Delay ◽  
Equivalence Ratio ◽  
Pressure Range ◽  
Ignition Delay Time ◽  
Light Emission ◽  
Pressure Rise ◽  
Effect Of Temperature ◽  
Pressure Transducers

Kerosene based hydrocarbon fuels are preferred candidates for the source of energy due to its stable properties. Based on the requirement of the combustor and the growing concern over pollutant, kerosene based fuels are modified. The fuel under investigation is a modified form of kerosene with ultra-low sulphur content. The effect of temperature on modified kerosene is studied for viscosity, surface tension, specific heat, density and ignition delay. The time delay for ignition of gas-phase mixtures of modified kerosene/oxygen have been measured using a shock tube facility. The experiments are conducted in the temperature range of 1200–1877 K, pressure range of 4–12 atm and equivalence ratio of Ø = 1.5, 1 and 0.5. The ignition delay time measurements were carried out using piezoelectric pressure transducers, which records the pressure rise due to ignition and simultaneously recording the light emission during the process of ignition using a photodiode. The ignition delay is represented as τign = 0.168841 × P−1.49 × Ø0.72 × e(14310/T)

An Investigation on Sensitivity of Ignition Delay and Activation Energy in Diesel Combustion

2015 ◽  
Vol 137 (9) ◽  
Author(s):  
Umashankar Joshi ◽  
Ziliang Zheng ◽  
Amit Shrestha ◽  
Naeim Henein ◽  
Eric Sattler
Keyword(s):  
Activation Energy ◽  
Ignition Delay ◽  
Cetane Number ◽  
Ignition Process ◽  
Start Of Injection ◽  
Auto Ignition ◽  
Time Period ◽  
Ignition Quality ◽  
Ignition Quality Tester ◽  
Start Of Combustion

The auto-ignition process plays a major role in the combustion, performance, fuel economy, and emission in diesel engines. The auto-ignition quality of different fuels has been rated by its cetane number (CN) determined in the cooperative fuel research engine, according to ASTM D613. More recently, the ignition quality tester (IQT), a constant volume vessel, has been used to determine the derived cetane number (DCN) to avoid the elaborate, time consuming, and costly engine tests, according to ASTM D6890. The ignition delay (ID) period in these two standard tests and many investigations has been considered to be the time period between start of injection (SOI) and start of combustion (SOC). The ID values determined in different investigations can vary due to differences in instrumentation and definitions. This paper examines the different definitions and the parameters that effect ID period. In addition, the activation energy dependence on the ID definition is investigated. Furthermore, results of an experimental investigation in a single-cylinder research diesel engine will be presented, while the charge density is kept constant during the ID period. The global activation energy is determined and its sensitivity to the charge temperature is examined.

An Investigation on Sensitivity of Ignition Delay and Activation Energy in Diesel Combustion

2014 ◽  
Author(s):  
Umashankar Joshi ◽  
Ziliang Zheng ◽  
Amit Shrestha ◽  
Naeim Henein ◽  
Eric Sattler
Keyword(s):  
Activation Energy ◽  
Ignition Delay ◽  
Cetane Number ◽  
Ignition Process ◽  
Start Of Injection ◽  
Auto Ignition ◽  
Time Period ◽  
Ignition Quality ◽  
Ignition Quality Tester ◽  
Start Of Combustion

The auto-ignition process plays a major role in the combustion, performance, fuel economy and emission in diesel engines. The auto-ignition quality of different fuels has been rated by its cetane number (CN) determined in the CFR engine, according to ASTM D613. More recently, the Ignition Quality Tester (IQT), a constant volume vessel, has been used to determine the derived cetane number (DCN) to avoid the elaborate, time consuming and costly engine tests, according to ASTM D6890. The ignition delay period in these two standard tests and many investigations has been considered to be the time period between start of injection (SOI) and start of combustion (SOC). The ignition delay (ID) values determined in different investigations can vary due to differences in instrumentation and definitions. This paper examines the different definitions and the parameters that effect ID period. In addition the activation energy dependence on the ID definition is investigated. Furthermore, results of an experimental investigation in a single-cylinder research diesel engine will be presented while the charge density is kept constant during the ID period. The global activation energy is determined and its sensitivity to the charge temperature is examined.

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