Site items in: Content by Author Hadi Nozari

Presentation

Based on its well-known merits ammonia has been gaining special attention as a potential renewable energy carrier which can be replaced in power generation systems. Considering its low flame speed and its potential for producing fuel NOx as the main challenges of combusting ammonia, flame stability, combustion efficiency, and NOx formation are experimentally investigated. Focus is on premixed ammonia-hydrogen-air flames with high mixture fractions of ammonia (60-90% by volume) under standard temperature and pressure conditions. We introduce silicon-carbide (SiC) porous block as a practical and effective medium for ammonia-hydrogen-air flame stabilization which enables stable and efficient combustion of the mixtures…

NOx emission analysis and flame stabilization of ammonia-hydrogen-air premixed flames
Presentation

Based on its well-known merits, ammonia has been gaining special attention as a potential renewable energy carrier which can be replaced in power generation units. One of the major challenges with ammonia as a fuel is NOx emission, which has a complex underlying chemical kinetics. In an earlier chemical kinetics study by the authors, NOx formation sensitivity was thoroughly studied in a wide range of combustion conditions [Nozari & Karabeyoğlu, J.Fuel 2015]. As the next step, premixed ammonia-hydrogen-air flames are studied experimentally in standard temperature and pressure condition. Effects of some major influential parameters on NOx emission levels are investigated:…

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

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…