GTA’s Fuel Technology for Two-cycle Engines

Summary

The two-cycle engine is commonly used for personal transportation on land and water and for many other applications. It has become the major cause of air pollution in many areas around the world. Newer, cleaner burning engines are being designed and may be a long term solution but they are not an answer for today. GTA has a product which modifies the two-cycle engine’s fuel to make it burn cleanly and more efficiently. It offers an immediate low-cost solution to the two-cycle pollution problem while it pays the consumer back in improved fuel economy.

The Two-cycle Engine Problem

Two-cycle engines have many advantages over four-cycle engines which make them ideal for use in motorcycles and outboard motors. For a given engine displacement it is lighter, smaller, produces more power and has fewer moving parts. As a result it is less expensive to manufacture, and it can be fitted to smaller, lighter chassis. The two-cycle engine is also more reliable and easier to maintain than a four-cycle engine.

Two-cycle engines, however, have a very important disadvantage. They are inefficient and produce more emissions of carbon monoxide and unburned hydrocarbons. It is reported by environmental groups that 30% of the fuel used by two-cycle engines goes out the exhaust. This results not only in a loss of energy, but the harmful emissions are so high that the two-cycle motorcycle is being banned from road use in the United States and new EPA regulations will effectively ban it from use in outboard motors. The loss of energy means that more fuel needs to be burned to make up for that loss. The power capacity of the engine is also a victim of incomplete combustion.

Engine manufacturers are working to develop lower polluting substitutes for the two-cycle.  Smaller four-cycle designs and modified two-cycles are being developed.  The new engines will be more expensive, more complicated and will not have many of the advantages of the current two-cycle.

Causes of Inefficiency and High Emissions From Two-cycle Engines

The inefficiency and high emissions from two-cycle engines are attributable to the basic way a two-cycle operates. Unlike a four-cycle engine which has separate fuel intake and exhaust strokes, in a two-cycle the fuel/air mixture enters the cylinder at the same time spent gasses are exhausted.  Mixing of the new fuel and the spent fuel gasses occurs causing non-uniform and incomplete combustion of the new fuel. The two-cycle pollution problem is compounded by the fact that lubricating oil is mixed with the fuel and must be burned along with it.

An additional and less well-known cause of inefficiency and high emissions is attributable to a basic property of gasoline which interferes with formation of a homogeneous fuel/air mixture in the cylinder. Gasoline is comprised of many different components which boil off or vaporize at different temperatures. Some vaporize almost immediately after entering the intake system. Some remain a liquid well into the combustion process.  What is happening is that components which vaporize at low temperatures leave behind droplets that vaporize only at much higher temperatures. This is called fractional distillation. The important point is that the gasoline phase of the fuel/air charge in the cylinder of an engine is not homogeneous. It has been demonstrated that this lack of gasoline component homogeneity leads to incomplete combustion and emissions. While the fractional distillation problem is common to two- and four-cycle engines, it is more pervasive in the two-cycle where the fuel contains very slow burning lubricating oil molecules and where the fuel mixes with spent gasses.

GTA’s Fuel Technology

GTA has proprietary technology which can be used to bridge the gap between today’s inefficient, high-emission, two-cycle engine and future cleaner designs. GTA uses a scientific phenomenon called viscoelasticity to solve the fractional distillation problem. Viscoelasticity means that a liquid can be made to have much greater viscosity when it is stretched, as in a spray. GTA uses a very small amount of high molecular weight polymer to make fuel viscoelastic. Fuel droplets formed when fuel is pulled from a carburetor instantaneously become viscous. The increased viscosity holds in the components which would normally escape and turn to vapor and fractional distillation is inhibited. Fuel droplets maintain their integrity until they are mixed with air in the cylinder where the heat is sufficient to vaporize all components simultaneously from the surface of the droplet. Slow burning fuel and oil molecules are burned simultaneously with more volatile fuel components. The result is a more uniform flame front and more complete combustion. Emissions and fuel consumption are reduced and power is increased.