Which factor affects the amount of air entrained into the plume during the growth stage?

• A. Location of fuel package
• B. Type of fuel
• C. Location of ignition
• D. Location of vent opening

Answer: (A)

Air entrainment into the plume during the growth stage is driven by how the heat source is arranged in the space and how the flame develops there. The location of the fuel package sets where the heat is released and how the plume forms relative to room boundaries. That geometry directly shapes the plume’s rise and the surrounding air it draws in. If the fuel is placed where the plume can rise freely and expand, entrainment tends to be more pronounced; if it’s tucked near walls or corners, the plume interacts with boundaries differently, altering how much ambient air is pulled into the plume.

Fuel type and ignition location matter for how much heat and initial flow you get, but they don’t control the entrainment amount as directly as where the fuel is located. Vent opening affects external air exchange and ventilation, not the internal entrainment dynamics of the plume itself.