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Fundamental Characteristics of Ammonia/Air Premixed Laminar Flames

Fundamental flame characteristics must be required for the design of ammonia fueled combustors. However, few studies of ammonia combustion have been conducted. In this study, fundamental ammonia/air premixed laminar flame characteristics, such as NO formation/reduction mechanisms and laminar burning velocity, were experimentally and numerically investigated. NO mole fraction in burned gas from ammonia/air premixed flames were investigated using a stainless-steel nozzle burner. Experiments were conducted at various equivalence ratios and pressures. As a result, NO mole fraction in burned gas reduced with the increase in equivalence ratio and pressure. Formation/reduction mechanisms of NO were numerically investigated. Laminar burning velocity and…

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Characteristics of Ammonia / N2 / O2 Laminar Premixed Flame in Oxygen-enriched Condition

The problems of ammonia fuel are a low combustion qualities compared with the combustion qualities of hydrocarbon fossil fuels. In this study, the laminar burning velocity was used as the indicator of the combustion quality. Since the laminar burning velocity of ammonia fuel is low compared with that of other fossil fuels, it is necessary to increase the combustion quality in order to utilize the ammonia as an alternative fuel in conventional combustion systems. In this study, the oxygen-enriched combustion was applied to an ammonia/N2/O2 premixed flame for achieving higher burning velocity. The effects of the oxygen-enriched combustion on the…

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Research and development of NH3-fueled solid-state fuel cell systems

Ammonia is a prospective carbon-free fuel source for fuel cell systems due to low production cost, ease in liquefaction at ambient temperatures, and high energy density. Furthermore, hydrogen and nitrogen originating from ammonia fuel are expected to have little negative effect on fuel cell performance, while hydrocarbon fuels draws some severe problems at electrodes, such as CO poisoning or carbon deposition in low- and high-temperature fuel cells, respectively. Several technologies can be considered for the ammonia utilization in fuel cell systems. For the utilization of ammonia fuel, we aim to develop a system combined with ammonia decomposition reactor and solid-state…

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Numerical investigation of combustion characteristics of ammonia-air mixtures under high pressure lean conditions

In this numerical study we investigate the combustion characteristics of ammonia-air mixtures at elevated pressure and lean conditions which are encountered in gas turbine combustors. The Konnov mechanism is implemented to predict the laminar burning velocity, autoignition, species concentrations and the sensitivity analysis of ammonia decomposition and laminar flame speed. A laminar premixed freely propagating flame model is implemented to calculate burning velocity, mole fractions of species, and contribution of reactions in molar conversion of specific species. Also a homogenous reactor model is used to analyze the temporal mole fraction of radicals and ignition delay time. Effects of adding hydrogen…

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My Solar Powered Ammonia Generation System

As a memorial to my father I have installed on the farm where he was raised, a demonstration Solar-Hydrogen system that has been producing and compressing hydrogen from solar power for several years. The hydrogen will be used to fuel a tractor which can also be fueled by ammonia. The ammonia was to be purchased until after last year’s conference when I was put in contact with Doug Carpenter, who has a low energy input catalytic method of making ammonia from hydrogen and nitrogen. I will describe the demonstration system that is being installed. It consists of a nitrogen generator…

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Recent progress on the Ammonia-Gasoline and the Ammonia-Diesel Dual Fueled Internal Combustion Engines in Korea

Both a spark ignition engine and a compression ignition engine are considered to use ammonia as primary fuel in this study. First, in a spark ignition engine, an ammonia-gasoline dual fuel system was developed and both ammonia and gasoline are injected separately into the intake manifold in liquid phase. As ammonia burns 1/6 time slower than gasoline, the spark timing is needed to be advanced near 40 degree before top dead center. The test engine showed quite high variation in the power output with ammonia supply more than 70% of the total heat value. As a result, 70% of gasoline…

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Liquid Ammonia for Hydrogen Storage

Hydrogen storage and transportation technology is essentially necessary to realize hydrogen economy. Hydrogen can be stored in many different forms, as compressed or liquefied hydrogen in tanks, or as hydrogen carriers: a hydrogen-absorbing alloy, metal hydrides with light elements, organic hydrides and carbon-based hydrogen storage materials. Among them, solid-state hydrides with light elements such as MgH2, Mg(BH4)2 and NH3BH3 possess high hydrogen capacity, 7-20 mass%, However, the practical volumetric H2 density is below 8 kgH2/100L because the packing ratio is down to 50%. Ammonia is easily liquefied by compression at 1 MPa and 25°C, and has a high volumetric hydrogen…

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Further Evolution of an Ammonia Fuelled Range Extender for Hybrid Vehicles

In a previous research the possibility to run a small 4-stroke twin-cylinder SI engine of 505 cm3 with ammonia plus hydrogen was demonstrated. Ammonia and hydrogen tanks were utilized to feed the engine while, apart, the suitability of a custom-designed catalytic reactor to produce hydrogen from ammonia with the required flow rate was verified as well. The experimental activity confirmed the need to increase combustion velocity by adding hydrogen to air-ammonia mixture, with energy ratios that mainly depend on load and less on engine speed. The minimum hydrogen to ammonia energy ratio was found below 6% at full load and…

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Expanding the Market for Renewable NH3

This report describes the market conditions for various projects using the Solid State Ammonia Synthesis (SSAS) Renewable NH3 process. We address the following activities: possible issues with the scale of the process, some schemes that induce a population to change fuel sources for their energy needs, financial requirements for the creation of new renewable energy sources and new SSAS plants. We discuss methods of monetization for producers, and some of the issues related to the risks of such monetization, and we suggest ways that Renewable NH3 can be a valuable investment as well as an energy source. The conclusion is…

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Ammonia Economy – The Global Potential

The development of the ammonia economy will depend on successful deployment of a range of new technologies in the context of the existing ammonia industry and the world’s many existing energy markets. This report will provide framework on: Supply/demand and status of the global ammonia industry. Plausible response of growth and prices in response to a giant new market in fuels. New incremental applications which may lead to ‘disruptive innovation’ and rapid takeoff for ammonia fuels. Barriers to takeoff.