• 한국연소학회:학술대회논문집
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• 2015.12a
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• pp.153-156
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• 2015

• Transactions of the Korean Society of Automotive Engineers
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• v.10 no.1
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• pp.76-83
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• 2002

Mathematically and chemically simplified reaction scheme for n(heptane that simulates autoignitions of the end gases in spark ignition engines has been developed and studied computationally. The five(equation model is described, to predict the essential features of hydrocarbon oxidation. This scheme has been calibrated against autoignition delay times measured in rapid compression machines. The rate constants, activation temperatures, Ta, Arrhenius pre-exponential constants, A, and heats of reaction for stoichiometric nheptane/air has all been optimized. Comparisons between computed and experimental autoignition delay times have validated the present simplified reaction scheme. The influences of heat loss and concentration of chain carrier at the beginning of compression upon autoignition delay times have been computationally investigated.

• Journal of the Korean Society of Combustion
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• v.17 no.2
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• pp.9-16
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• 2012

Iso-octane, n-heptane and their blends were tested in a constant volume combustion chamber to measure laminar flame speeds. The experimental apparatus was automatically controlled to enhance the accuracy and data acquisition speed. A large database of laminar flame speeds at elevated temperatures and pressures was established. From this database, laminar flame speeds of iso-octane, n-heptane and their blends were investigated and analysed to derive new correlation to predict laminar flame speeds at any blending ratio. The new flame speed model was successfully applied to these fuels with limited range of errors.

• Journal of ILASS-Korea
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• v.16 no.4
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• pp.167-175
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• 2011

The HCCI engines have been known with high efficiency and low pollution and can be actualized as the new internal combustion engines. However, As for(??) the ignition and combustion depend strongly on the oxidation reaction of the fuel, so it is difficult to control auto-ignition timing and combustion duration. Purpose of this paper is creating the database for development of multi-dimensional simulation and investigating the influence of different molecular structure. In this research, the effect of n-heptane mole ratio in fuel (XnH) on the ignition delay from homogeneous charge compression ignition(HCCI) has been investigated experimentally. By varying the XnH, it was possible to ascertain whether or not XnH is the main resource of ignition delay. Additionally, the information on equivalence ratio for varying XnH was obtained. The tests were performed on a RCM (Rapid Compression Machine) fueled with n-heptane and iso-octane. The results showed that decreasing XnH (100, 30, 20, 10,0), the ignition delays of low temperature reaction (tL) and high temperature reaction (tH) is longer. And the temperature of reaction increases by about 30K. n-heptane partial equivalence ratio (fnH) affect on tL.and TL. When ${\phi}$nH was increased as a certain value, tL was decreased and TL was increased.

• Journal of ILASS-Korea
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• v.21 no.1
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• pp.20-28
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• 2016

This paper presents an experimental study on the GDI injector with Bosch method. The injection characteristics, such as the injection quantity, the injection rate, the maximum velocity of the nozzle exit and the injection delay were studied through the change of the injection pressure, the tube pressure and energizing duration in injection rate measurement device using nheptane. The injection quantity is increased by increasing injection pressure, decreasing tube pressure or increasing energizing duration. As the difference of the injection quantity changed, the shape of injection rate was moved with a constant form. The maximum velocity of the nozzle exit showed a tendency to increase as the injection pressure is increased. However, tube pressure did not affect. Overall, it was confirmed that the closing delay is longer than the opening delay in all conditions. As the injection pressure increased, the result has a tendency to decrease the closing delay, it did not affect the opening delay. Reduction of the closing delay showed the reduction of the injection duration. the tube pressure and energizing duration did not affect the injection delay (opening delay, closing delay).

• Applied Chemistry for Engineering
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• v.22 no.4
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• pp.390-394
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• 2011

Vapor liquid equilibria were measured for the binary systems of ditetrahydrofurfurylpropane (DTHFP) and some solvents such as cyclohexane, n-heptane, tetrahydrofuran, and water. Binary vapor liquid equilibria were measured for the diluted concentration range of DTHFP. NRTL model was used to analyze the measured data. With the experimental data, binary interaction parameters of the NRTL model were regressed.