A motor or motor is a machine designed to convert a form of energy into mechanical energy . An engine can be classified into a category according to two criteria: the form of energy it accepts to create movement and the type of movement it produces.
As a general rule, engines have an axle, which in rotary offset and through mechanical devices such as drive gears. The exceptions are rocket motors and linear motors . Nowadays, combustion engines…
The Stirling cycle is a thermodynamic cycle that describes the operation of a class of equipment (generating or operating machines). The cycle describes the original Stirling engine that was invented and patented in 1816 by the Reverend Robert Stirling, helped substantially by his brother engineer.
The Stirling engine is an external combustion engine. This characteristic differentiates it from other types of engines such as the otto engine or the diesel engine which are internal combustion engines. Both engines operate according to the otto cycle and the diesel cycle respectively.…
The theoretical Otto cycle is the ideal cycle of the Otto engine. The Otto engine is also known as a spark ignition engine because the ignition of the fuel is done through a spark caused by a spark plug. It is also known as a gasoline engine because of the type of fuel it uses.
One way to study the performance of this engine is by analyzing its theoretical cycle. The theoretical cycle is an approximation to the real cycle with many simplifications. In practice, there are so many variables that affect the performance of the engine that calculating the actual cycle is practically impossible.…
The theoretical diesel cycle is the theoretical cycle of a diesel engine, also known as a compression ignition engine.
The theoretical cycle of a thermal engine is a theoretical approximation of its operation to calculate its performance.
The cycle of an internal combustion engine is constituted by the physical and chemical transformations suffered by the fuel during its passage inside the engine.
The study of a real cycle taking into account all the numerous variables, represents a very complex problem. For this reason, it is usually simplified by resorting to theoretical…
A boiler is a container, or a set of tubes, used to heat water or other fluid. To heat the liquid can be used various fuels such as diesel, coal, biomass, etc. The most common are fossil fuels. Operation and applications of a boiler
The boiler is a machine or apparatus is designed to heat water or other fluid, usually by combustion of a fuel such as gas, diesel, coal, biomass, etc. The hot or vaporized fluid leaves the boiler for use in different heating processes or applications, generation of motive power from steam, cooking or cleaning. The two most common boiler types are:…
In the 2-stroke motors, the operating cycle is carried out in two races. The admission of the active fluid must be made during a fraction of the compression stroke, and the exhaust must be produced during a fraction of the working stroke.
For this to be verified, it is necessary that the active fluid be pre-compressed to be able to enter the cylinder and that the exhaust of the combustion gases be carried out by its own pressure.
The 2-cycle cycle was conceived to simplify the distribution system, eliminating and reducing the number of valves, and to obtain a greater power with…
Cycles theoretical endothermic engines
For theoretical cycles, commonly used approaches aproximacióna by the real conditions are three:
- real cycle
- air cycle
- air-fuel cycle.
A theoretical these cycles are compared in practice the actual cycles, which are obtained experimentally by means of the indicators, for this reason, the actual cycle also indicated cycle is called.
Although the theoretical cycles do not correspond to actual cycles, provide a useful reference for the thermodynamic study of internal combustion engines,…
The Stirling engine is an external combustion thermal engine. Originally it was conceived as an industrial main engine to compete with the steam engine, but in practice, for more than a century it was only used for domestic applications and for low power engines.
The Stirling engine was invented in 1816 by Robert Stirling, a Scottish priest. One of the concerns of the time was the safety of steam engines. Stirling's goal was to get a less dangerous engine than the steam engine.
The operation of the Stirling engine is based on the expansion and contraction of a gas that can be…
Between the Otto real cycle and the corresponding theoretical Otto there are substantial differences. Some of these differences can be observed when comparing the diagram of the real cycle with the theoretical cycle diagram. The other differences that we are going to analyze refer to the differences between the temperature and pressure values of the two Otto engine cycles. Differences in the form of the diagram
The difference in shape of the diagram between a real Otto cycle and a theoretical Otto cycle consists of a different profile in the expansion and compression curves, in…
The first figure shows a diagram of a typical indicated 2-stroke engine. We need not make a detailed description thereof will suffice to clarify some obscure points, examination of the corresponding path diagram as a function of angular displacement of the crank. This diagram illustrates the second figure.
Nor is there, in this case, correspondence between "time" and "race", for convenience of exposition we have matched the start of the two-stroke points that correspond, respectively, at the beginning of phase COMBUSTION , n at the start of the scanning phase.
A) First Half. Point…
A butterfly valve is a device to regulate or interrupt the flow of a fluid in a conduit. The butterfly valve allows to increase or reduce the passage section by means of a plate which rotates on an axis. This plate is called a butterfly. By decreasing the fluid passage area, the local pressure drop in the valve increases, reducing fluid flow.
Butterfly valves can be distinguished in the field of hydraulics according to the following characteristics:
- They are in all cases contained within the pipeline;
- They have a low pressure drop when fully open.
- The relationship…
The development of the Stirling engine started with the aim of being an alternative to the machine of value due to certain advantages that it had with respect to the then popular steam engine.
Over time, certain disadvantages compared to internal combustion engines have left the Stirling engine in the background. Advantages of the Stirling engine compared to internal combustion engines
The main advantages of a Stirling engine compared to an otto engine, a diesel engine or a steam engine are:
- The maintenance facility
- They are quieter engines
The operating system of the thermal engines is based on a cycle that is constantly repeated. In the case of internal combustion engines this cycle consists of the fuel input (admission), combustion of the fuel, expansion of the cylinder and expulsion of the gases produced. This cycle generates a mechanical movement, if the cycle repeats we will have a constant mechanical movement.
A thermal engine can work through many different cycles. In this section we will explain the different operating cycles that an internal combustion engine can have, the real cycles and the theoretical cycles.…
Second law of thermodynamics
No real or ideal engine can turn all the heat introduced into mechanical work.
Therefore, only a fraction of the heat supplied by the combustion will be converted into work; This fraction represents the thermal performance of the engine. Then we define,
Ideal thermal performance
Relation between the amount of heat transformed into useful work and the amount of heat supplied to the fluid.
As useful work equals the difference between the supplied…