Carbon Dioxide Effect on Self-Ignition

Gaseous carbon dioxide is considered as a potentially efficient diluent causing suppression of blast processes in H2 + air/02 mixtures. In connection with that, by way of example, estimates of H2 + CO2 + air self-ignition delay within practicable pressure and temperature ranges have been made. 

It should be noted that some inhibition of these processes show up as an increase in the absolute values of delay time. The most noticeable growth in the delay time t, was recorded in the intermediate temperature range (the same as it is for the water steam), which is seen in Fig. 6.37. 

Here the y-coordinate is where t,co2 is for mixtures with CO2 content. 

Dependencies for t, and the anticipated changes are plotted in Figs. 6.36 and 6.37 at constant temperature in the combustible mixture. 

It is different for the case of mixture detonation the velocity of the shock front leading the detonation decreases when an inert gas is added. The change in the selfignition delay time behind the detonation wave in a stoichiometric H2 + air -H CO2 mixture is shown in Fig. 6.38. To help with better understanding. Fig. 6.39 presents diagrams of the CO2 and N2 effect on temperature and pressure in a shock-compressed triple mixture of H2 + air -1- diluent. 

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