Diesel emission improvements by the use of oxygenated DME/diesel blend fuels

Tosun

et al. 2017

mijst

Section: Introductionmentioning

confidence: 99%

EFFECT OF MgO NANOPARTICULE ADDITIVES ON PERFORMANCE AND EXHAUST EMMISSIONS OF DIESEL FUELLED COMPRESSION IGNITION ENGINE

Tosun

et al. 2017

mijst

“…The performance, suitability and proper diesel engine operation of diesel-DME blends have already been reported in different works [18,19]. Therefore, taking into account these promising results, studies under well-controlled laboratory conditions may help to understand the influence of DME addition on the behavior of soot precursors in the overall oxidation process.…”

mentioning

confidence: 99%

Influence of dimethyl ether addition on the oxidation of acetylene in the absence and presence of NO

Marrodán

Berdusán

Aranda

et al. 2016

Fuel

The use of oxygenated compounds as additives to diesel fuels is considered nowadays as a promising alternative for minimizing soot emissions and maybe also NO x under appropriate conditions [1,2]. Classical oxygenated compounds include alcohols and ethers, and among them, ethanol (C 2 H 5 OH) and dimethyl ether (CH 3 OCH 3 , DME) are two of the most popular candidates to be used as additives. The use of ethanol has been extensively studied in the last years and it is already being used in reformulated gasolines, like E85 (85% ethanol and 15% gasoline) [3]. Similarly, DME has received considerable attention because of its high cetane number, vaporization characteristics, low toxicity, and low tendency to produce smoke and volatile organic compounds (VOCs) [4]. Additionally, DME can be produced from renewable materials [5,6].Ethanol and DME have the same molecular formula (C 2 H 6 O) but different structure and functional group, and, as it has been discussed in several previous works (e.g. [7,8]), the oxygen content and the specific structure of the oxygenated compound strongly influence the capacity for pollutant emission minimization. Song et al. [9] concluded that, under the conditions of their modeling study, both DME and ethanol were effective in reducing aromatic species (important soot precursors). However, DME exhibited a greater effectiveness due to its higher enthalpy of formation, which led to a higher final flame temperature and consequently to a decrease in aromatic species production in premixed flames [10], but also because of its structure. For fuel-rich conditions, the reaction flux analysis conducted by these authors [9] determined that reactions involving DME convert only approximately 15% of its carbon to C 2 -species (key species in the production of aromatic species), whereas reactions of ethanol convert approximately 35% of its carbon to C 2 -species. AbstractDimethyl ether (DME) is a promising diesel fuel additive for reducing soot and NO x emissions, because of its interesting properties and the possibility of a renewable production. An experimental and modeling study of the oxidation of acetylene (C 2 H 2 , considered as an important soot precursor) and DME mixtures has been performed under well-controlled flow reactor conditions. The influence of temperature, air excess ratio (λ) and presence of NO on the oxidation process has been analyzed. Under fuel-rich conditions, the presence of DME in these mixtures modifies the radical pool delaying the acetylene consumption. C 2 H 2 and DME, and the radicals generated in their conversion, interact with NO achieving different levels of NO concentration diminution depending upon the operating conditions. Under fuel-lean conditions, the presence of DME in the mixtures increases the NO diminution, whereas for the other values of λ considered, the maximum NO decrease reached is lower than that obtained in the case of pure acetylene.

“…Cetane number of DME (>55) is higher than that of diesel (46)(47)(48)(49)(50)(51)(52)(53)(54)(55) and for this reason it can be auto-ignited easily as compared to diesel and most other biodiesels. From experimental investigations researchers have estimated a cetane number of 68 for DME [115,191,192].…”

Section: Fuel Propertiesmentioning

confidence: 99%

“…Absence of carbon-carbon bond in its chemical structure helps to reduce soot emissions during combustion, but the same affects lubrication property of the fuel leading to wear and tear of moving parts that comes in contact with the fuel [29,193,194]. Oxygen rich fuel property of DME also helps to reduce PM as the absence of C-C bond inhibits the formation of PM and cause high oxidation of particulates [195][196][197]. The low viscosity and density of DME possess fuel handling issues.…”

Section: Fuel Propertiesmentioning

confidence: 99%

See 1 more Smart Citation

A study on the control of NOx and particulate matter emissions from dimethyl ether combustion in compression ignition engines

Thomas¹

Dimethyl Ether (DME) is a new age fuel developed mainly from coal and natural gas to use in compression ignition (CI) engines relatively easily with minimum modifications. One of the advantages of DME combustion in CI engines is the low emission levels of NOx and particulate matter (PM) in comparison with diesel combustion. Therefore, utilization of DME as an alternative fuel in CI engines can potentially meet stricter emission regulations with less effort.The thesis starts with a review of the body of experimental and numerical research on NOx and PM emissions from DME combustion, with the objective being to identify the most promising methods for emission control in DME fuelled engines. With DME being already available in several countries the current research interest is to optimize the engine performance in a cost-effective way with least modifications to existing technologies while minimizing combustion emissions to meet even the strictest emission regulations.Gaseous emissions from DME combustion are a well-researched topic while PM emissions, especially UFPM were neglected so far. However, PM emissions will become a major concern under the future emission norms such as Euro VI. A major part of the introduction and literature review discusses some of the novel methods of emission control