Determination of laminar burning characteristics of a surrogate for a pyrolysis fuel using constant volume method

A fast pyrolysis biofuel, mainly consisting to 98% of ethanol, ethyl acetate, diethyl ether, acetone and 2-butanone with mass ratios of 9:6:2:1:1, was catalytically produced from rice husk. A preliminary engine test demonstrated this biofuel has the possibility of being a gasoline blending stock. However, its fundamental burning features are not fully understood. This work presents the experimental investigations of the spherical propagating flame of a surrogate fuel representing the biofuel in a constant volume combustion chamber (CVCC). Tests were conducted at initial pressures of 0.1-0.4 MPa, initial temperatures of 358-418 K, and equivalence ratios of 0.7-1.4. Employing the constant volume method (CVM) allows determining laminar burning speeds (S-u) of this surrogate at conditions far beyond the initial conditions (0.1-0.8 MPa, 358-490 K). Power law fitting correlations between S-u and pressure were obtained via the constant volume method (CVM). Cellularity appears when pressure or temperature is high, and cellular burning speed was calculated by CVM as well. S-u determined via the constant pressure method (CPM) were compared with those from the CVM. Discrepancies between the results from the CVM and the CPM are within 15%, except at the conditions where flame cellularity appeared. Additionally, an explicit correlation of S-u was obtained from the experimental results. (C) 2019 Elsevier Ltd. All rights reserved.