What does a flame need to be sustained?

For a flame to be sustained, it requires oxygen as a critical component of the combustion process. Combustion occurs when a fuel reacts with oxygen, producing heat and light. In the presence of sufficient oxygen, the fuel reaches its ignition temperature, resulting in a flame. Without adequate oxygen supply, the combustion reaction cannot proceed, leading to incomplete combustion or extinguishment of the flame.

While high pressure can enhance combustion in certain conditions, it is not a fundamental requirement for sustaining a flame. Excess fuel may not contribute to a stable flame either, as it can lead to incomplete combustion and soot formation without sufficient oxygen to facilitate the reaction. Low temperature is counterproductive for sustaining a flame, as flames require a specific minimum temperature to initiate and maintain the combustion process. Thus, oxygen is the essential element needed to sustain a flame effectively.