Hydrogen/carbon monoxide syngas burning rates measurements in high-pressure quiescent and turbulent environment

A high-pressure, double-chamber, fan-stirred, large-scale explosion facility is proposed for measurements of laminar and turbulent burning velocities, SL and ST, of centrally-ignited hydrogen and carbon monoxide syngas/air mixtures over an initial pressure range of p = 0.1–1.0 MPa. Results show that lean syngas laminar flames at elevated pressure are highly unstable resulting in cellular structures all over the expanding flame front surface, where SL∼p−0.15 having a relatively modest decrease with pressure as compared to lean methane flames where SL∼p−0.50. Contrarily, as to lean syngas turbulent flames, values of ST increase with increasing pressure (ST∼p0.15) at a fixed r.m.s. turbulent fluctuating velocity (u′ ≈ 1.4 m/s). Moreover, it is also shown that increasing u′/SL is still a way much more effective in increasing values of ST/SL than increasing pressure. Finally, discussions are offered and area for further studies identified.

► A high-pressure large explosion facility for syngas combustion is proposed. ► Measurements of high-pressure burning velocities for expanding lean syngas flames. ► More gentle pressure effect on burning rates for syngas than methane. ► Higher efficacy of turbulent intensity in increasing turbulent burning velocities.