Engineering topics

Law, C. K.

Publications and source records attributed to Law, C. K..

20 records · Page 2

NASA NTRS1982

An experimental study on extinction and stability of stretched premixed flames

Law et al. (1981) and Ishizuka et al. (1982) have experimentally investigated the effects of flame stretch, preferential diffusion, and downstream heat loss on the extinction and stability of propane/air flames. The obtained results suggest that in the case of rich propane/air mixtures downstream heat loss, in addition to flame stretch, is needed for flame extinction. In the case of lean mixtures, flames can be extinguished by flame stretch alone. The data obtained in connection with the present study provide convincing evidence regarding the correctness of the previous results on the nature of flame extinction due to stretch. It is found that, in accordance with theoretical predictions, extinction by stretch alone is possible only when there is a deficiency regarding the less mobile reactant.

Ishizuka, S.↗

NASA NTRS1981

Lean-limit extinction of propane/air mixtures in the stagnation-point flow

The extinction limits of lean propane/air mixtures in the stagnation-point flow of a flat surface were mapped as functions of the surface temperature and the mixture concentration, velocity, and temperature. The maximum flame temperatures and the flame locations were also measured. The results show that the extinction limits are extremely insensitive to the nature of the surface, which can be heated to 1000 C. On the other hand preheating the gas mixture increases the flame temperature by an almost equal amount and therefore significantly extends the extinction limits. It is also found that at extinction the maximum flame temperatures and the flame locations, which when scaled with the velocity gradient, assume almost constant values independent of the other system variables investigated.

Law, C. K.↗