perfect combustion
complete combustion

Owing to the imperfection of this image, we obtain mere smoke instead of perfect combustion.

A blue rather than yellow flame within the cylinder meant that perfect combustion was achieved, promised GM's ad men.

Catalytic converters are designed to work best when the exhaust gases passing through them are the result of nearly perfect combustion.

It was hypothesized that gas turbine combustions during haze-free periods when oxygen level would be sufficient to achieve perfect or near perfect combustion.

Assuming perfect combustion conditions, such as complete combustion under adiabatic conditions (i.e., no heat loss or gain), the adiabatic combustion temperature can be determined.

Aimé Argand had perfected his cylindrical wick lamp which provided a central current of air through the burner, thus allowing the more perfect combustion of the gas issuing from the wick.

Assuming an ideal engine with no friction, perfect insulation, perfect combustion, a compression ratio of 10:1, and a g of 1.27 (for gasoline-air combustion), the theoretical efficiency of the engine would be 46%.