Practical measurements of premixed laminar burning velocities and markstein numbers of iraqi diesel-oxygenates-air blends

Abstract EN

Laminar burning velocities and Markstien length for blends of Iraqi dieseloxygenates (methanol, ethanol, subflowers biodiesel and yellow grease biodiesel)-air premixed flames are investigated using the spherically expanding flame with central ignition, using constant volume and thermocouples connected to data acquisition system.

Unstretched laminar burning velocity, Markstein lengths, Lewis number, Zeldovichnumber and Karlovitz number were obtained at wide range of equivalence ratios (Ø from 0.2 to 1.7).

The Study indicates that although the tested blends are diesel-oxygenates, laminar burning velocities give an obvious difference which demonstrates that thr molecular composition has a great effect on laminar burning velociries of fuels.

Maximun laminar burning velocity values occurs around equivalence ratios Ø =1.1.

Increasing equivalence ratio influnced Markstein lengths to be decrease for the tested blends-air mixtures.

The Zeldovich number maximum values obtained at stoichiometric equivalence ratio (Ø = 1.0).

The results show that the Markstein lengths were relatively independent of Karlovitz numbers.