Question

how do you calculate effect of pressure on the Lower Flammability Limit of a hyrocarbon, that is, how do you determine how pressure changes affect the LFL and UFL?

Answer 1

The influence of iniinitial pressure is not much of initial temperature.

Decreasing initial presspre below the atmosphere pressure will narrow the flammable range by increasing LFL and Decreasing UFL untill limit pressure is reached.

Similarly when increasing the pressure above the atmosheric will widen the flammable range by decresing LFL and increasing UFL.

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