High-pressure hydrogen/carbon monoxide syngas turbulent burning velocities measured at constant turbulent Reynolds numbers

摘要

Using a double-chamber explorsion facility, we measure high-pressure turbulent burning velocities (S_t) of lean syngas (35%H_2/65%CO) spherical flames at constant turbulent Reynolds numbers (Re_t = u'L_1/v) varying from 6700 to 14,200, where the root-mean-square turbulent fluctuation velocity (u') and the integral length scale (L_I) are adjusted in proportion to the decreasing kinematic viscosity of reactants (v) at elevated pressure (p) up to 1.2 MPa. Results show that, contrary to popular scenario for turbulent flames, at constant Re_T, S_T decreases similarly as laminar burning velocities (S_L) with increasing p in minus exponential manners. Moreover, at constant p, S_t/S_L increases noticeably with increasing Rex. It is found that the present very scattering S_t/S_l data at different p and Re_T can be nicely merged onto a relation of S_T/u' = 0.49Da~(0.25), where Da is the turbulent Damkohler number and values of Sr/u' tends to level-off when Da > 160 and p > 0.7 MPa.