Abstract
Development and validation of a new reduced dimethyl ether-air (DME) reaction mechanism is presented. The mechanism was developed using a modular approach that has previously been applied to several alkane and alkene fuels, and the present work pioneers the use of the modular methodology, with its underlying H/C1/O base mechanism, on an oxygenated fuel. The development methodology uses a well-characterized H/C1/O base mechanism coupled to a reduced set of fuel and intermediate product submechanisms. The mechanism for DME presented in this work includes 30 species and 69 irreversible reactions. When used in combustion simulation the mechanism accurately reproduced key combustion characteristics and the small size enables use in computationally demanding Large Eddy Simulations (LES) and Direct Numerical Simulations (DNS). It has been developed to accurately predict, among other parameters, laminar burning velocity and ignition delay times, including the negative temperature regime. The evaluation of the mechanism and comparison to experimental data and several detailed and reduced mechanisms covers a wide range of conditions with respect to temperature, pressure and fuel-to-air ratio. There is good agreement with experimental data and the detailed reference mechanisms at all investigated conditions. The mechanism uses fewer reactions than any previously presented DME-air mechanism, without losing in predictability.
Highlights
With the realization that global warming and air pollution as a result of fossil fuel combustion are increasing threats to human health and the environment, the demand for clean sources of energy is increasing
Among biofuels with a potential to be extensively used in the near future, dimethyl ether, abbreviated as dimethyl ether-air (DME) and with the molecular formula CH3 OCH3, ranks highly according to some evaluations [1]
DME is the simplest ether compound, and from a molecular structure point of view, the absence of carbon-carbon bonds and the available oxygen in the molecular structure gives it advantageous characteristics for compression ignition combustion engines
Summary
With the realization that global warming and air pollution as a result of fossil fuel combustion are increasing threats to human health and the environment, the demand for clean sources of energy is increasing. These three mechanisms include a wide range of number of species (48 to 433) and reactions (284 to 1004) yet can all be classified as chemically complex They cover the modelling of the laminar burning velocity, major species concentrations and ignition delay time, for a wide range of equivalence ratios, pressures and temperatures. These combustion parameters, at these wide ranges of conditions, are all targets that the novel reduced mechanism presented here aim to model, making these three detailed mechanisms suitable as references to compare to. The presented reaction mechanism is compared to experimental data and several available detailed and reduced reaction mechanisms for DME combustion
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
