Thermodynamic Efficiency
The reason why most devices are not capable of producing the claimed improvements is based in thermodynamics. This formula expresses the theoretical efficiency of an engine:
where h is efficiency, rv is the compression ratio, and g is the ratio of the specific heats of the gases before and after combustion.
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%.
For example, if an automobile typically gets 20 miles per gallon with a 20% efficient engine that has a 10:1 compression ratio, a carburetor claiming 100MPG would have to increase the efficiency by a factor of 5, to 100%. This is clearly beyond what is theoretically or practically possible. A similar claim of 300MPG for any vehicle would require the engine (in this particular case) that is 300% efficient, which violates the Second Law of Thermodynamics.
Extremely efficient vehicle designs capable of achieving 100MPG+ (such as the VW 1l) do not have substantially greater engine efficiency, but instead focus on better aerodynamics, reduced vehicle weight, and using energy that would otherwise be dissipated as heat during braking.
Read more about this topic: Fuel Saving Device
Famous quotes containing the word efficiency:
““Never hug and kiss your children! Mother love may make your children’s infancy unhappy and prevent them from pursuing a career or getting married!” That’s total hogwash, of course. But it shows on extreme example of what state-of-the-art “scientific” parenting was supposed to be in early twentieth-century America. After all, that was the heyday of efficiency experts, time-and-motion studies, and the like.”
—Lawrence Kutner (20th century)