The Role of Molecule Clustering by Hydrogen Bond in Hydrous Ethanol on Laminar Burning Velocity

Abstract

The role of hydrogen bond molecule clustering in laminar burning velocities was observed. The water in hydrous ethanol can change the interaction between water-ethanol molecules. A certain amount of water can become oxygenated which increases the burning velocity. The hydrogen bond interaction pattern of ethanol and water molecules was modeled. Based on the molecular model, azeotropic behavior emerges from ethanol-water hydrogen bond, which is at a 95.1%v composition. The interaction with water molecule causes the ethanol molecule to be clustered with centered oxygenated compound. So, it supplies extra oxygen and provides intermolecular empty spaces that are easily infiltrated by the air. In the azeotropic composition, the molecular bond chain is the shortest, so hypothetically the burning velocity is anticipated to increase. The laminar burning velocity of ethanol fuel was tested in a cylindrical explosion bomb in lean, stoichiometric, and rich mixtures. The experimental result showed that the maximum burning velocity occurred at hydrous ethanol of 95.5%v composition. This discrepancy is the result of the addition of energy from 7.7% free ethanol molecules that are not clustered. At the rich mixture, the burning velocity of this composition is higher than that of anhydrous ethanol.

The Role of Hydrogen Bonding on Laminar Burning Velocity of Hydrous and Anhydrous Ethanol Fuel with Small Addition of n-Heptane

“…(b) Anhydrous ethanol is added with n-heptane. [12] showed that the composition of azeotropic hydrous ethanol occurs at a 95.1% v composition with the molecular structure as in Figure 9(a). The maximum burning velocity of hydrous ethanol occurs at a 95.5% v composition with the molecular structure as in Figure 9(b).…”

“…Therefore, the objective of this study is to acquire new data about laminar burning velocity of the mixtures of anhydrous ethanol (99.7% v) and hydrous ethanol (95.5% v) with n-heptane in varied composition at lean ( = 0.9), stoichiometric ( = 1), rich ( = 1.1), and very rich mixture ( = 1.2). It is motivated by the characteristics of hydrous ethanol fuel which is better than anhydrous ethanol at the stoichiometric and rich mixture [12]. The mixture of ethanol/nheptane can combine the renewable fuel with fossil fuel.…”

“…in which is the radius of spherical flame front and is the time when the radius is measured. The stretched rate ( ) of spherical flame is obtained at any captured image on the flame surface [12], as follows:…”

Addition of bio-additive as a catalyst of burning vegetable oil influenced by 4 pole magnetic field

“…Many factors affect the combustion process, among which are fatty acids, polarity and the potential of electricity from fatty acids. Gas-fired research has also been examined by [8,9], revealing speed in the combustion chamber. The results showed that the hydro ethanol combustion rate was higher than anhydrous ethanol and N-Heptane in the stoichiometric mixture.…”