Investigation of C8-C12 Paraffins’ Fundamental Combustion Characteristics and Surrogate Fuel Model

Abstract

In order to investigate fundamental combustion characteristics of high carbon number paraffins and their role in surrogate fuel model of aviation fuel, ignition delay time and laminar premixed flame speed of iso-octane, n-decane and n-dodecane were measured under different initial conditions. Ignition delay time and laminar premixed flame speed were measured in shock tube and constant volume combustion chamber respectively. The experimental results show that ignition delay times of iso-octane and n-dodecane are relatively sensitive to the variation of equivalence ratio in low temperature and high temperature range, while n-decane’s influence by equivalence ratio is comparatively uniform in the entire temperature range; laminar premixed flame speed of iso-octane is sensitive to the variation of initial pressure under lean and rich fuel conditions, while n-dodecane couldn’t be ignited successfully in combustion chamber and gave flame speed data. Under overall consideration, n-dodecane is recommended as constitute of surrogate fuel model of aviation fuel which has high ignition point and is hard to combust, while high proportion iso-octane can be employed in surrogate fuel model which is sensitive to equivalence ratio, and high proportion n-decane can be employed in model which changes mildly with equivalence ratio.