Different Types of Combustion Engines

Internal combustion engine is famous for its high thermal efficiency, compact structure, strong maneuverability and simple maintenance. Modern internal combustion engine is became the most important heat machinery in the RC industry.

Of course, combustion engine also has some disadvantages: it has a high requirement on the fuel oil. You cannot use the fuel with bad quality or solid fuel. Internal combustion engine is a device using the fuel to fire in the cylinder and produce heat energy, then transform the heat energy directly into mechanical energy and supply the power.It was divided into diesel and gasoline engine by the fuel used, most of the agricultural internal combustion engine is diesel engine; while for the RC model airplane, the gasoline engine seems to be used more. Gasoline engine and diesel engine have its own characteristics. Airplane gasoline engine has a high speed, low noise, easy to start and low cost of manufacturing. The diesel engine has a large compression ratio, high thermal efficiency, its economic performance and emission performance are all better than a gasoline engine.

According to the operating cycle, it was divided into four-stroke internal combustion engine and a two-stroke internal combustion engine. Turn the crankshaft for two laps (720 °), the piston reciprocating movement up and down inside the cylinder for four stroke, to complete a working cycle of internal combustion engine is called four stroke internal combustion engine; while turn the crankshaft for one laps (360 °), the piston reciprocating movement up and down inside the cylinder for two stroke, to complete a working cycle of internal combustion engine is called two stroke internal combustion engine. RC airplane engine is widely used in the two-stroke internal combustion engine. According to the number of cylinders, it can be divided into single cylinder and multi-cylinder internal combustion engine. There is only one cylinder of the engine called single cylinder engine; two or more cylinders engine called a multi-cylinder engine. Such as double cylinder, three cylinders, four, five, six, eight cylinder, twelve cylinders are all belong to multi-cylinder engine, etc.

According to the cylinder arrangement, it can be divided into vertical, horizontal, tilting, upright and v-shaped arrangement. Single engine, in which each cylinder in a row is generally vertical arrangement, but sometimes in order to reduce the height, it is also decorated the cylinder into declining or level; the double column type engine divided the cylinder into two columns. The angle between the two columns less than 180° (usually 90°) is called V type engine, and if the angle between the two columns equal to 180°, then we called it as opposed engine.

Comparing the ignition way of the fuel in the cylinder, it can be divided into pressure combustion engine and ignition combustion engine. From the sight of inlet pressure, combustion engines can be divided into supercharged and un-supercharged (natural air inlet). Gasoline hobby engine is always using the naturally aspirated, while the in order to improve the power, diesel engine usually using supercharged way.

There are three ways to cool an overheated engine, which include water-cooled, air-cooled and composite cooling. Cooling water is the water removing heat from a machine or system. Cooling water may be recycled through a recalculation system or used in a single pass once-through cooling system. While the air-cooled engine is cooled rely on the circulation of air directly over hot parts of the engine.

Comparing RC Gas Engines with Glow Engines

A "glow engine" is what as a kid we used to call "gas engines", but the truth of the matter is, they do not burn gasoline. The biggest feature of gas engines are easier to start and fuel-saving, while glow engines are fuel-consumption, and cannot be used for large scale models…