Oxyhydrogen Research Articles

Thermodynamics of gases: combustion processes, analysed in slow motion

We present a number of simple demonstration experiments recorded with high-speed cameras in the fields of gas dynamics and thermal physics. The experiments feature relatively slow combustion processes of pure hydrogen as well as fast reactions involving oxy–hydrogen in a stoichiometric mixture.

Investigations on generation methods for oxy-hydrogen gas, its blending with conventional fuels and effect on the performance of internal combustion engine

In order to overcome the drawbacks of the regular petroleum fuel, it is the need of time to completely or partially replace the petroleum fuel. But alternative options to petroleum fuel are having disadvantages. An electric or compressed air driven cars cannot be used where high torque is required or using hydrogen as fuel requires very costly storage equipments. In this research work an attempt has been made to reduce the drawbacks of petroleum fuels. Electrolysis of water can give us hydrogen in form of oxy-hydrogen gas which can be used as an alternative fuel for any internal combustion engine. This research paper discusses various methods designed for the production of oxy-hydrogen gas. Later blend of ‘oxy-hydrogen gas’ and petrol or diesel is used instead of only petrol/diesel to study the influence of the ‘oxy-hydrogen gas’ on the performance of the internal combustion engine. Oxy-hydrogen gas is an enriched mixture of ‘hydrogen’ and ‘oxygen’ bonded together molecularly and magnetically. Oxy-hydrogen gas is produced by electrolysis of water using caustic soda or KOH as the catalyst. Presence of ‘oxy-hydrogen gas’ during combustion process decreases the ‘brake specific fuel consumption’ and also increases the ‘brake thermal efficiency’. Water is one of the by-products of the combustion process which also decreases the temperature of the combustion process. It is safe to use ‘oxy-hydrogen gas’ as it is not stored but is produced and used as and when required. Together with ‘brake thermal efficiency’ engine shows improvement in the ‘brake thermal efficiency’ with the blend of fuel. All together it has been observed that the blend of ‘oxy-hydrogen gas’ and petrol instead of only conventional fuel improves the performance of the engine. Key words: Oxy-hydrogen gas, alternative fuels.

Characterization of La<SUB>0.8</SUB>Sr<SUB>0.2</SUB>MnO<SUB>3±<I>δ</I></SUB> Nanopowders Synthesized by Aerosol Flame Synthesis for SOFC Cathode

Lanthanum strontium manganite (La(0.8)Sr(0.2)MnO(3 +/- delta), LSM) powders with a high specific surface area (55.26 m2/g) were successfully synthesized by aerosol flame synthesis (AFS) technique. The crystallinity and morphology of the synthesized powders sintered at various temperatures were studied by XRD, TEM and BET. The synthesized powders exhibited spherical shape mostly in a few nanometer ranges with a relatively high crystallinity due to thermal plasma reactions in a high temperature of oxy-hydrogen flame. To analyze electrochemical performances of synthesized LSM powders, impedance spectroscopy (IS) was carried out with the symmetric cells prepared by slurry based electrostatic spray deposition (ESD) onto the YSZ electrolyte pellet. The interfacial polarization resistances were 3.04 ohms cm2 at 750 degrees C which is relatively lower than that of micro-porous film (7.24 ohms cm2) applying micro-sized powders deposited on same condition.

A microfluidic chip integrated with a microoptical lens fabricated by femtosecond laser micromachining

We report on the integration of microlens and microfluidic channels in fused silica glass chip using femtosecond laser micromachining. The main process includes three procedures: (1) femtosecond laser scanning for forming a hemispherical surface and a Y-shaped channel in the fused silica glass; (2) chemical etching of the sample for removal of the modified areas; and (3) oxyhydrogen (OH) flame polish for smoothening the surface of the microlens. In addition, we demonstrate that the fabricated microlens exhibits good imaging performance with a 5× magnification, showing great potential in future lab-on-a-chip applications.

Characterization of a method for aerosol generation from heavy fuel oil (HFO) as an alternative to emissions from ship diesel engines

This work describes a laboratory method to synthesize aerosols with properties similar to those emitted by ocean going ships. In this method, an oxy-hydrogen flame burner nebulizes and combusts heavy fuel oil (HFO). The oil was fed to the burner via a syringe pump at a maximum rate of 15 ml/h. Adjusting the feed temperature of the oil and the use of a quenching ring in the burner, it is possible to obtain an aerosol with a mode diameter of about 11 nm. This is close to the reported 5–8 nm for the nano-mode of ship emissions. Filter samples were also analyzed for elemental carbon, organic carbon and anion composition. No elemental carbon mass was detected and only a few sulfur containing compounds were present. A chemical equilibrium model was applied for both oxy-hydrogen flame and 2-stroke ship diesel engine combustion conditions to predict equilibrium concentrations, chemical formula and phase of vanadium and nickel containing compounds. The model confirmed that the real-world ship diesel engine and the oxy-hydrogen flame burner combustion processes produced the same vanadium, nickel and sulfur particulate matter (PM) products in terms of chemical formula and phase. Both the 5–8 nm particles from real-world ship emissions and the laboratory synthesized particles contain transition metals. Transmission electron microscope (TEM) images of laboratory synthesized particles show similar morphology to those sampled from a ship. Cloud condensation nuclei (CCN) measurement indicates that neither laboratory generated nor ship emitted aerosol is hygroscopic. To our knowledge, this is the first time the 5–8 nm particles emitted from ships have been aptly synthesized on a laboratory scale.

Catalytic oxidation kinetics of iron-containing carbon particles generated by spraying ferrocene-mixed with diesel fuel into a hydrogen–air diffusion flame

Kinetic measurements of the catalytic oxidation of iron-containing soot particles were made for a better understanding of the role of catalytic particles in the initiation of soot oxidation. Carbon-based iron-containing soot particles were generated by spraying ferrocene-mixed with diesel fuel into an oxy-hydrogen flame. A commercial carbon black was used as a standard. Their oxidative kinetics and physico-chemical characteristics were measured by thermogravimetric analysis, secondary ion mass spectrometry, X-ray diffraction, gas-cell Fourier-transform infrared spectroscopy, induced coupled plasma-atomic emission spectroscopy, and high-resolution transmission electron microscopy. It was found that a tiny amount of ferrocene led to a significant reduction in both the on-set temperature and the activation energy of soot oxidation. Catalytic oxidation occurred in two consecutive steps, as temperature increased. The initiation of oxidation, even with an addition of ferrocene, was controlled mainly by surface oxygen complexes and partly by the long-range crystalline order of the carbon graphene layer. However, once catalytic oxidation began, the progress of the reaction was mainly determined by the amount of ferrocene that was added.

Effect of condensed products of silane combustion on a low-pressure oxyhydrogen flame

The kinetics of branching-chain oxidation of monosilane and hydrogen at and near the first explosion limit at temperatures within 630–850 K and pressures below 1 torr was studied. Atomic hydrogen and oxygen were observed in the silane-oxygen reaction zone. The effects of the reactor walls treated with silane-lean (1: 9: 10) and silane-rich (1: 1: 3) SiH4-O 2-He mixtures on the parameters of oxyhydrogen ignition were different. This modification of the surface was of long-term character. Water vapor was absorbed on the hot reactor walls treated with explosions of the silane-rich mixture. Such a surface was demonstrated to affect the combustion of oxyhydrogen, inducing pulsating combustion.

Fabrication of Sn/SnO 2 composite powder for anode of lithium ion battery by aerosol flame deposition

Crystalline SnO 2 and Sn/SnO 2 composite nano-powder were synthesized by aerosol flame deposition (AFD) method employing an oxy-hydrogen flame torch and a heated deposition turn-table. The aqueous precursor solution of the tin (IV) chloride and methyl alcohol was atomized with an ultrasonic nebulizer and subsequently carried into the central tube of the torch by flowing dry Ar gas. SnO 2 were formed by oxy-hydrogen flame and deposited on a substrate placed in a heating stage. To produce Sn metal particles and control the ratio of Sn/SnO 2, as-synthesized SnO 2 were heat-treated under 5% H 2 and 95% Ar mixed gas atmosphere at a temperature of 150 °C for 3 h, and then at 600 °C for 1–4 h. The average particle size of as-synthesized SnO 2 was in the range 5–15 nm and that of Sn/SnO 2 composite powder was slightly grown to 20–90 nm depending on the heat treatment temperature. The analysis on morphology, crystalline phases, and chemical state of Sn revealed that AFD method is one of the favorable approaches to produce nano-sized Sn/SnO 2 composite powder with good morphology, size distribution, and well-controlled Sn/SnO 2 ratio.

A planar micro-flame ionization detector with an integrated guard electrode

The flame ionization detector (FID) quantifies small concentrations of organic compounds by flame ionization of hydrocarbons and measurement of the resulting ion current. The ion current represents the number of carbon atoms in the sample gas. The miniaturization of the FID by MEMS technology (µFID) is expected to increase its use, because of reduced oxyhydrogen consumption. This loosens safety precautions and makes portable applications possible. In contrast to a former µFID design, the current planar µFID is designed to prevent environmental air from entering the system and deteriorating the measurement signal. The oxyhydrogen flame burns in the silicon plane of an almost completely encapsulating glass–silicon–glass sandwich. Only a small opening remains for removal of the exhaust gas from the system. In between the detector electrodes, a guard electrode is integrated to intercept and by-pass leak currents past the picoammeter, which then only measures the ion current. Due to the design of the guard electrode, small leak currents are still measured by the picoammeter. Yet, these leak currents can be corrected for to obtain the ion current. Measurements of the ion current as a function of the applied voltage and the sample gas flow show expected FID behaviour.

Morphology and luminescence properties of BaMgAl10O17:Eu2+ blue phosphors by Aerosol Flame Deposition

BaMgAl10O17:Eu2+ (BAM:Eu) is widely used as a blue phosphor for fluorescent lamps and plasma display panels (PDP). The improvement of the luminescence efficiency is a significant issue for applications in plasma display panels. In this study, the Aerosol Flame Deposition (AFD) was applied to fabricate BaMgAl10O17:Eu2+ (BAM:Eu) particles with spherical shape and fine size in order to improve their luminescence. The sub-micrometer powder was synthesized in spherical shape in an oxy-hydrogen flame and deposited on a substrate in the form of porous film. The particle size of as-prepared powder increased with increasing the concentration of precursor solution and the heat treatment under reducing atmosphere increased particle size additionally with surface roughening due to the needle-like crystallized phases. Photoluminescence spectrum was observed at about 450nm due to the 5d–4f transition of Eu2+ and the intensity of phosphor was as high as 70% of that of the commercial phosphor.

Improvement of transparency and durability to deep ultraviolet light in fluorine-doped silica glass fiber by optimizing the preform fabrication process

Fluorine-doped silica glass fiber was fabricated as fiber-core for transmittance of deep ultraviolet wavelength region. By examining the effect of oxyhydrogen flame onto the core-glass (conventional cleaning process called fire-polishing process), it was found to create oxygen-deficiency centers. Additionally, fire-polishing process changes the distribution of fluorine concentration near core-cladding interface and leads to the deterioration of the optical characteristics of the fiber. By conducting preform fabrication without fire-polishing, the obtained fluorine-doped silica glass fiber showed high transmittance of more than 92% m -1 at 266 nm and excellent durability after 4 G pulses of 7 mJcm -2 laser irradiation.

Thermal shock study of α-alumina doped with 0.2% MgO

Thermal shock behaviour of α-alumina doped with 0.2% MgO is studied. A uniformly mixed powder of α-alumina, magnesia and 2% PVA solution is dried, granulated and uniaxially pressed into circular discs of 30 mm diameter and 3 mm thick. The discs are sintered at a maximum temperature in the range of 1500–1650 °C for 3 h. The thermal shock test is carried out by heating the sample with an oxy-hydrogen flame and by monitoring the crack formation by acoustic emission technique. In general, the samples possess high thermal shock resistance close to their melting temperature. The spinels formed due to MgO doping possess low fusion temperature which hinders the crack growth. The same has been confirmed from scanning electron microscope (SEM) studies. The samples sintered at lower temperature possess higher thermal shock resistance than those sintered at higher temperature. This is attributed to the higher porosity. The abnormal grain growth (AGG) associated with high sintering temperature might have contributed to lowering of thermal shock resistance. To summarize, MgO-doped alumina samples possess high thermal shock resistance by avoiding the catastrophic failure due to the formation of low fusion spinels.

Electrochemical characteristics of LiCoO 2 nano-powder synthesized via aerosol flame deposition (AFD)

Crystalline LiCoO 2 nano-powders for lithium-ion battery were synthesized by aerosol flame deposition (AFD). The aqueous precursor solution was atomized with an ultrasonic vibrator and supplied to the oxy-hydrogen flame by flowing dry Ar gas. The as-deposited soot powders were collected on a substrate placed on a heating stage. X-ray diffraction and transmission electron microscopy (TEM) show that the soot powders were composed of nano-sized particles of Li 2CO 3, CoCo 3 and Co 3O 4 and the subsequent heat treatments at 700 °C for 5 h that converted these powders to well-layered LiCoO 2 powder. The flow rate of H 2 flame gas was discovered to have influenced the phase composition in the as-deposited soot. The electrochemical performance of synthesized nano-powders was investigated using 2032 coin-type cell. LiCoO 2 nano-powder synthesized at an H 2 flow rate of 2.5 l/min sintered at 700 °C for 5 h showed a first discharge capacity of 144 mAh/g and good rechargeability in Li//1 M LiPF 6-EC/DEC//LiCoO 2 cells between 3 and 4.3 V.

Fabrication of LiCoO 2 cathode powder for thin film battery by aerosol flame deposition

Crystalline LiCoO 2 nano-particles for thin film battery were synthesized and deposited by aerosol flame deposition (AFD). The aqueous precursor solution of the lithium nitrate and cobalt acetate was atomized with an ultrasonic vibrator and subsequently carried into the central tube of the torch by flowing dry Ar gas. LiCoO 2 were formed by oxy-hydrogen flame and deposited on a substrate placed in a heating stage. The deposited soot film composed of nano-sized particles was subsequently consolidated into a dense film by high temperature heat treatment at 500–800 °C for 5 h and characterized by SEM, XRD, and Raman spectroscopy. The crystalline carbonates and oxide were first formed by the deposition and the subsequent heat treatment converted those to LiCoO 2. The FWHMs of the XRD peaks were reduced and their intensity increased as the heat treatment temperature increased, which is due to improved crystallinity. When judged from the low enough cation mixing and well-developed layered structure, it is believed that the LiCoO 2 film satisfied the quality standard for the real application. SEM measurements showed that LiCoO 2 were nano-crystalline structure with the average particle size <70 nm and the particle size increased with the increase of heat treatment temperature. The thickness of thin film LiCoO 2 before the consolidation process was about 15 μm and reduced to about 4 μm after sintering.

Preparation of high-purity TeO2-ZnO glass batches

Tellurium oxide-zinc oxide glass batches have been prepared through chemical vapor deposition from tellurium and zinc alkyl compounds in an oxyhydrogen flame onto the lateral surface of rotating cylindrical substrates. The composition of the deposits has been shown to be determined by the relative amounts of the metalorganic precursors in the gas phase. Varying the deposition conditions, we obtained both amorphous and crystalline deposits, with concentrations of metallic impurities below 1 ppmw. Melting the deposits, we prepared high-purity (TeO2)1 − x (ZnO) x (0.15 ≤ x ≤ 0.35) glasses.

Fast fragmentation of metal oxide nanoparticles via reduction in oxyhydrogen flame

Fast fragmentation of 20nm iron oxide and 60nm tin oxide nanoparticles into a few nanometer nanoparticles in a diffusion oxyhydrogen flame is reported. The phenomenon is explained by the in situ reduction of generated 20–60nm nanoparticles. The fragmentation occurs due to reduction induced instability in the oxygen-deficient surface. Simulated experiments with electron irradiation and characterization with x-ray absorption spectroscopy substantiated this mechanism. This finding may open a route to continuously generate a few nanometer scale nanoparticles of various oxides in a flame synthesis.

Controlling low-pressure flame conditions by affecting the cold service lines located far from the heated reactor

A study was performed of a low-pressure oxyhydrogen flame in an isothermal regime in the diffusion-controlled region of heterogeneous chain termination. The chain propagation and termination sites were widely separated in space. Controlling the chain loss conditions made it possible to carry out isothermal combustion of the mixture in the diffusion-controlled region and to verify the proposition of the Semenov theory that the propagation of a chain explosion in time near the limit can be described by a linear model. From a comparison of calculated and experimental data, gas-surface interaction with a variable rate constant was found and the range of variation of this constant during one ignition was determined. The large differences between the kinetic curves obtained previously for various modes of chain termination on the wall were found to be related primarily to heterogeneous chain interaction, which governs the gas-phase process in the kinetic region and has a weak effect on this process in the diffusion-controlled region of chain termination.

High birefringence fibre Bragg gratings written in tapered photonic crystal fibre with femtosecond IR radiation

High birefringence Bragg gratings were written with ultrafast 800 nm radiation in non-birefringent pure silica core photonic crystal fibres (PCF) that were tapered with an oxy-hydrogen flame. The grating spectra indicate that a birefringence above 10−3 was created in the tapered PCF.

Fabrication of Li 2O–B 2O 3–P 2O 5 solid electrolyte by flame-assisted ultrasonic spray hydrolysis for thin film battery

Li 2O–B 2O 3–P 2O 5 glass soot was fabricated from aqueous precursor solution of a CH 3CO 2Li·2H 2O and BCl 3, POCl 3 by the flame-assisted ultrasonic spray hydrolysis. The aqueous precursor solution of the lithium acetates was first atomized with an ultrasonic vibrator (1.7 MHz). B 2O 3 and P 2O 5 were formed from BCl 3 and POCl 3 by oxy-hydrogen flame. Their properties were investigated by SEM, XRD, TGA–DSC and impedance analyzer. The formed particles in glass soot had spherical shape and the size of approximately 50–100 nm. XRD analysis revealed that the amorphous phase and crystalline phases were mixed in glass soot and the crystalline phases were B(OH) 3 and B 2O 3. The crystalline B(OH) 3 and B 2O 3 found in glass soot completely disappeared by heat treatment. Conductivity was measured by complex impedance method using impedance analyzer and the conductivity was 10 −8 S/cm.

Heterogeneous chain propagation in low-pressure flames

An analysis of papers on hydrogen combustion at low pressures is performed, which refines the contribution of the catalytic reactions on the reactor wall to the gas-phase part of the process. A new model for the heterogeneous loss of active reaction centers was proposed and tested experimentally to explain inconsistencies that occur in some papers. In this model, the diffusion region of chain termination is formed under standard experimental conditions in vacuum oxyhydrogen flames at a reactor gas pressure a thousand times lower than the boundary pressure postulated by the previous models as the pressure below which the diffusion region of chain termination cannot be formed.