Laminar burning speeds and flame structures of spherically expanding flames mixtures acetylene (C2H2) with air have been investigated over a wide range equivalence ratios, temperatures, pressures. Experiments conducted in constant volume cylindrical vessel two large end windows. The was installed shadowgraph system equipped high speed CMOS camera, capable taking pictures up to 40,000 frames per second. Shadowgraphy used study transition from smooth cellular during propagation. Pressure...

This study presents fundamentals of spray and partially premixed combustion characteristics directly injected methane in a constant volume chamber (CVCC). The vessel is cylinder with inside diameter 135 mm height mm. Two end the are equipped optical windows. A high speed complementary metal oxide semiconductor (CMOS) camera capable capturing pictures up to 40,000 frames per second used observe flow conditions chamber. fuel jet generates turbulence forms turbulent heterogeneous fuel–air...

The effects of hydrogen addition, diluent injection pressure, chamber temperature and turbulence intensity on methane–air partially premixed turbulent combustion have been studied experimentally using a constant volume (CVCC). fuel–air mixture was ignited by centrally located electrodes at given spark delay times 1, 5, 40, 75, 110 ms. Experiments were performed for wide range volumetric fractions (0% to 40%), simulated 25% as diluent), pressures (30–90 bar), (1–3 temperatures (298–432 K)...

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 conventional counterparts. The effect of chemical composition on key performance aspects such as ignition delay, laminar burning speed, and emission been experimentally studied. However, the development mechanism predict those parameters for GTL is still in early stage. aviation...

Onset of auto-ignition premixed gas-to-liquid (GTL)/air mixture has been determined at high pressures and low temperatures over a wide range equivalence ratios. The GTL fuel used in this study was provided by Air Force Research Laboratory (AFRL), designated Syntroleum S-8, which is derived from natural gas via the Fischer–Tropsch (F–T) process. A blend 32% iso-octane, 25% n-decane, 43% n-dodecane employed as surrogates for chemical kinetics study. spherical chamber, can withstand up to 400...

Laminar burning speed and ignition delay time behavior of iso-octane at the presence two different biofuels, ethanol 2,5 dimethyl furan (DMF), was studied in this work. Biofuels are considered as a better alternative source fossil fuels. There is potentiality that combustion characteristics can be improved using biofuels an oxygenated additive. In study, three blending ratios 5%, 25%, 50% ethanol/iso-octane DMF/iso-octane were investigated. For laminar calculation, equivalence ratio 0.6–1.4...

A numerical study has been carried out to investigate the impact of adding syngas into JP-8 fuel. new chemical mechanism assembled from existing and examined by comparing with experimental data literatures. The was then applied Cantera zero-dimension constant internal energy volume model one-dimensional (1D) freely propagating flame calculate ignition delay time laminar burning speed, respectively. simulations were over a large range temperature (700–1000 K), blending ratio (0–20% syngas),...

Ethanol is considered one of the most attractive renewable energy sources in modern days. A chemical mechanism on ethanol generated this work to predict performance fuel engine-relevant operating conditions. To build mechanism, a reaction generator (RMG) utilized. The compared against experimental results find its accuracy. Important reactions responsible for are selected through sensitivity and path flux analysis. rate parameter important further adjusted from available literature data....

Abstract The next generation of advanced combustion devices is being developed to operate under ultra-high-pressure conditions. However, such extreme conditions, flame tends become unstable and measurement fundamental properties as the laminar speed becomes challenging. One potential method resolve this issue measuring ignition-affected region during spherically expanding experiments. in more resistant perturbations remains smooth due high stretch rates (i.e. small radii). Stable propagation...

Measurement of laminar burning speed is complex and costly. Therefore, engineering correlations this thermo-chemical property with other simpler-to-measure fundamental combustion properties, such as minimum ignition energy, are desired. Two different between energy have been developed. The first correlation the form Sl = a energy−1/3 second b energyc, where a, b, c fitting constants. accuracies these fits were close to each other.

The rate-controlled constrained-equilibrium (RCCE), a model order reduction method, has been further developed to simulate the combustion of propane/oxygen mixture diluted with nitrogen or argon. RCCE method assumes that nonequilibrium states system can be described by sequence subject small number constraints. new approach is applied oxidation propane in constant volume, internal energy over wide range initial temperatures and pressures. USC-Mech II (109 species 781 reactions, without...

This work is an experimental and computational study to investigate the effect of capacitive discharge ignition (CDI) on plasma kernel formation flame propagation air–propane mixture. paper mainly focused characteristics, pressure rise, time, velocity field, species concentrations. A conventional system used for comparison purpose. constant volume combustion chamber with 400 cm3 designed study. utilized visualize as well induced from two sources. The experiments are performed in a wide range...

Turbine blade surfaces are cooled by jet flow from expanded exit holes (EEHs) against the prevailing hot gas flow. The through EEH must be designed to form a film of cool air over blade. Computational analyses performed examine cooling effectiveness suction side solving conservation equations and ideal equation state for turbulent compressible For sufficiently high coolant mass rate, EEH, which acts as converging–diverging nozzle, is choked at nozzle throat, resulting in supersonic flow,...

Chemical composition and thermodynamics properties of different thermal plasmas are calculated in a wide range temperatures (300–100,000 K) pressures (10−6–100 atm). The calculation is performed dissociation ionization temperature ranges using statistical thermodynamic modeling. considered this study enthalpy, entropy, Gibbs free energy, specific heat at constant pressure, ratio, speed sound, mean molar mass, degree ionization. calculations have been done for seven pure such as hydrogen,...