Steam engine principle is to convert the energy of steam into mechanical work.
The appearance of the steam engine had caused the industrial revolution in the 18th century. It remained the world's most important prime mover until the beginning of the 20th century, when it gradually gave way to the internal combustion engine and the steam turbine, among others. A steam engine requires a boiler that boils water to produce high-pressure steam, and this boiler can use wood, coal, oil or natural gas, or even combustible garbage as a heat source. The steam expands to push a piston to do work.
Construction of a steam engine:
The steam engine is mainly composed of a cylinder, a base, a piston, a crank linkage mechanism, a slide valve steam distribution mechanism, a speed control mechanism and a flywheel. The cylinder and base are stationary parts.
In a steam boiler, water is boiled into steam through the process of combustion. The steam is sent to the cylinder through pipes. Valves control the time the steam reaches the cylinder, through the main steam valve and throttle valve into the slide valve chamber, controlled by the slide valve alternately into the left or right side of the cylinder, pushing the piston movement. The steam pushes the piston to do work in the cylinder, and the cooled steam is introduced into the condenser through the piping to be recondensed into water. This process is repeated as the steam engine moves.
The average steam engine has three cylinders in a bank. The steam engine directly translates the up and down motion of the pistons into the rotational motion of the ship's shaft. Newer steam engines also contain a small turbine, and the steam from the cylinders can be used to increase the efficiency of the entire drive by using its waste heat to drive this turbine. This turbine is also connected to the ship's propeller shaft.
Classification:
Boiler classification
The fire-tube model was used in the boilers of early ships and steam locomotives.
In a fire-tube boiler, the hot smoke from the combustion chamber is discharged through a flue by a chimney. This type of boiler requires a relatively tall chimney.
The water in the tube molding is heated by hot gas through a number of pipes. These pipes flow into a steam collection chamber at the top of the exchanger. An important advantage of the water tube boiler is that it poses less danger in the event of damage, the reason for this is that the amount of water in the boiler is relatively small, in addition to the fact that there are not many moving mechanical components in the boiler that would be subject to wear and tear, some water tube boilers also have a heat exchanger on the exhaust flue to increase the thermal efficiency of the whole boiler.
Steam engine classification
By steam working on one or both sides of the piston, the steam engine can be divided into single-acting and double-acting two kinds;
By the way the cylinder is arranged, it can be divided into vertical and horizontal; according to the expansion of the steam is in a cylinder or sequentially expanding continuously in a number of cylinders, it can be divided into a single-expansion type and multi-expansion; by the direction of flow of steam in the cylinder. According to the flow direction of steam in the cylinder, it can be divided into reflux type and single-flow type;
According to the way of steam discharge and discharge pressure, it can be divided into condensing type, atmospheric type and back-pressure type.
The above is what I shared today, I hope it can help you.