An internal combustion engine (ICE) is a heat engine in which fuel combustion occurs inside the cylinder. During combustion, heat is released, which is used to expand gases. The piston moves under the pressure of the expanding gases.
Thus, in an internal combustion engine, thermal energy is converted into mechanical energy.
Marine internal combustion engines are classified according to a number of criteria. For an engine to operate, it is necessary to ensure a certain sequence of processes: filling the cylinder with air, compressing it, supplying fuel and combustion, expanding combustion products and removing exhaust gases. This series of processes occurring sequentially in the cylinder, ensuring continuous operation of the engine, is called the work cycle. The part of the working cycle that occurs during one stroke of the piston is called stroke.
Thus, according to the implementation of the working cycle, engines are divided into four-stroke, in which the working cycle is completed in four piston strokes or two revolutions of the crankshaft, and two-stroke, in which the working cycle is completed in two piston strokes or one revolution of the crankshaft.
According to their design, engines are divided into trunk, crosshead and with oppositely moving pistons (OPP) in one cylinder.
During engine operation, when fuel is burned in the cylinder, gas pressure acts on the piston. It can be represented in the form of a concentrated force P (Fig. 1, a), applied to the piston pin axis and directed downward. When the crankshaft is rotated through a certain angle, force P is decomposed according to the parallelogram rule into two forces: P Ш, acting along the axis of the connecting rod and driving the crankshaft, and P N, acting perpendicular to the direction of movement of the piston. The force РН presses the piston against the cylinder wall and causes increased wear of the pistons and cylinder walls
Rice. 1. Scheme of the design of engines: a - trunk; b - crosshead; c - with oppositely moving pistons in one cylinder
According to this scheme, high-speed and medium-speed engines, called trunk engines, are made (their piston has a developed lower cylindrical part - trunk).
For high-power engines, the RN force is high, so they are made crosshead (Fig. 1, b). The piston 2 of such an engine is rigidly connected through the rod 3 to the crosshead 1, the slider 4 of which moves in the guide parallels 5. The lateral force P N in this case is perceived not by the cylinder wall, but through the crosshead by parallels that are rigidly connected to the engine frame. Crossheads are made single-sided or double-sided.
For engines with PDP (Fig. 1, c), the fuel burns in a chamber located between two pistons 1, which operate in the same cylinder and move in opposite directions. This engine has two crankshafts 2.
Depending on the arrangement of the cylinders, engines are single-row with a vertical cylinder arrangement (Fig. 2, a) and V-shaped (Fig. 2, b).
Rice. 2. Engine diagram: a - in-line; b - V-shaped; in - naturally aspirated; g - supercharged
According to the method of filling the cylinder with fresh charge, they are distinguished:
- naturally aspirated engines (Fig. 2, c), in which air is sucked through the valve by a piston (four-stroke) or the cylinder is filled with air by a purge pump at low pressure, slightly exceeding atmospheric pressure (two-stroke);
- engines in which fuel is injected into the working cylinder under pressure created by a special pump K (blower).
According to the method of ignition of the combustible mixture in the cylinder, they are distinguished:
- engines in which fuel is injected into the working cylinder through a special device (injector) under the influence of pressure created by the fuel pump; it is finely sprayed, mixed in a cylinder with air, highly heated as a result of compression, and spontaneously ignites (these are diesel engines);
- carburetor engines, i.e. engines in which fuel is mixed with air not in a cylinder, but in a special device, a carburetor, from which the combustible mixture is supplied to the engine cylinder and ignited there by an electric spark obtained from a special system.
Based on speed, engines are conventionally divided into low-speed with an average piston speed of less than 6.5 m/s and high-speed with an average piston speed of more than 6.5 m/s.
Based on rotation speed, engines are divided into:
- low-speed (LS) - 10...25 s -1 (100...250 rpm),
- medium speed (SOD) - 25...60 s -1 (250...600 rpm),
- high speed - 60...100 s -1 (600...1000 rpm)
- high-speed - over 1000 s -1 (10,000 rpm).
By power, engines are divided into:
- low-power - up to 73.5 kW (100 hp),
- average power - 73.5...735 kW (100...1000 hp) and
- heavy-duty - over 7350 kW (10000 hp).
According to their purpose, engines are main, which ensure the propulsion of the vessel, drive the propellers, and auxiliary, which serve to drive electric generators, compressors and other auxiliary mechanisms.
Based on the method of changing the direction of shaft rotation, motors are divided into reversible and non-reversible. Forward and reverse motion with a fixed pitch propeller can be achieved by changing the direction of rotation of the propeller. To provide reverse motion, the propeller can be rotated in the opposite direction in two ways: either by changing the direction of rotation of the engine crankshaft, or just the propeller.
In reversible engines, you can change the direction of rotation of the crankshaft. The power of these engines is usually high.
The crankshafts of non-reversible engines rotate in only one direction. For high-speed and low-power non-reversible engines, the direction of rotation of the propeller is changed using a reversible gear installed between the engine and the shaft line.
To briefly designate the type of engine, diesel plants use conventional markings (Table 1). The engine type marking, common among domestic diesel plants and individual among plants in other countries, usually consists of letter symbols written in a certain sequence for individual engine characteristics and numbers indicating the number of cylinders, diameter, and piston stroke (in cm).
In accordance with GOST 4398-78, the marking of USSR engines consists of a digital designation of the number of cylinders, conventional letter designations of engine characteristics, after which the cylinder diameter and piston stroke in cm are shown in fractions.
Thus, the brand 8DP 43/61 stands for: eight-cylinder two-stroke reverse trunk (no letter K), naturally aspirated (no letter H) engine with a cylinder diameter of 430 mm and a piston stroke of 610 mm.
In the same way, the brand 6DKPH 74/160 means: a six-cylinder, two-stroke, crosshead, reversible, supercharged engine with a cylinder diameter of 740 mm and a piston stroke of 1600 mm.
The marking of engines produced in the GDR includes the number of cylinders and piston stroke. The cylinder diameter is either given in the denominator or not indicated at all. For example, the engine brand 8ZD 72/48 stands for: eight-cylinder two-stroke diesel with a piston stroke of 720 mm and a cylinder with a diameter of 480 mm.
The piston stroke is not indicated in the markings of Sulzer engines. For example, the 8TD-48 brand is assigned to an eight-cylinder trunk reversible engine with a cylinder diameter of 480 mm.
In the marking of MAN engines, the number of cylinders is indicated between the conventional letter designations of the engine design and its stroke, after which the cylinder diameter and piston stroke (in cm) are indicated as a fraction, then the turbocharging designation and the modification indicator. Thus, the engine brand K6Z 60/105L means that the engine is a crosshead six-cylinder two-stroke with a cylinder with a diameter of 600 mm, a piston stroke of 1050 mm, the under-piston spaces of this modification are used as a purge pump.
Engines from the Burmeister and Wein factories are labeled slightly differently. Here, the cylinder diameter (in cm) is indicated ahead of the symbols, after the number of cylinders, and the piston stroke is indicated after them. Thus, grade 6-35 VBF62 is assigned to a six-cylinder two-stroke reversible diesel engine with gas turbine supercharging with a cylinder diameter of 350 mm and a piston stroke of 620 mm.
There are many situations when you simply need to find out the engine model. For example, when buying a car or just spare parts. And then the question arises: how and where to get this information? Next, we will tell you how to determine the engine model in the following ways: find the number on the engine using the engine compartment plate and the VIN code.
On the engine itself
Let's say right away that looking for the number on the engine is not the easiest way. Although, it would seem: he opened the hood, found the engine, found the number and entered it into the search engine. But it's not that simple.
Where is the engine number
Firstly, the number can be stamped on a variety of places on the engine. It all depends on the make and model of the car. Although more often it can be found on the top part, the one closer to the windshield. well and Secondly, the number itself may be in such a state that it is impossible to figure it out without a rust remover and a brush, or even completely destroyed by corrosion.
Interesting fact! Some US-made cars simply do not have a number on the engine. This only applies to older models.
What information is written there?
Once you have found the engine number, you can begin to parse the information that it represents. Although, depending on the brand, there are some differences, the markings generally consist of 14 characters. They are conventionally divided into two blocks: descriptive (6) and indicative (8).
Pay attention to the first one. The first three digits in the descriptive block indicate the base model index. This is followed by the modification index (if there is none, put zero), climate version and either the Latin “A” (meaning diaphragm clutch) or “P” (recirculation valve). In the index part, the year of manufacture is first indicated (by a number or letter of the Latin alphabet), then the month (by the next two digits). The remaining 5 characters indicate the serial number.
Remember! Numbers from 1 to 9 indicate the years of manufacture 2001-2009, Latin “A” - 2010, B - 2011, C - 2012, etc.
Sign under the hood
We will tell you further how to find out the engine model by wine, and now let’s pay attention to the plate on which this is also indicated. It is located under the hood of most passenger cars and is called the engine compartment. Using numbers and letters, all the necessary information is provided here (car model, engine type, cylinder capacity, frame number or identification number, color code and trim code, drive axle, manufacturer and type of transmission). Depending on the make of the car, it may be supplied in different sequences. To decrypt, you will have to use special literature or appropriate resources.
Did you know?The design of the first internal combustion engine was presented in the 17th century by the Dutch inventor Christiaan Huygens.
Find out the engine by VIN code
The third method will explain how to find out the engine model by VIN code. Vehicle Identification Number, abbreviated as VIN. They began assigning this number to cars in America and Canada. This is a unique identification number consisting of 17 numbers and letters. With its help you can find out almost everything about a particular car. And, of course, there is information about the engine model. It is enough to look at the car’s registration certificate to find out the data (from the year of modification to the code) of the engine by vin.
Although you can do without it by looking at the code on the machine itself. Since there are no strict rules for the location of the VIN code, it can also be seen near the passenger seat. But more often it is located between the windshield and the engine.
The VIN code is divided into 3 parts of three, six and eight characters. Only numbers and Latin letters are used (except I, O, Q due to the similarity with numbers). The first speaks about the manufacturer, the second describes the vehicle, the third is distinctive.
The first and third characters indicate the country, manufacturer and type of vehicle, that is, this is the world code of the manufacturer. In order to find out the engine modification by VIN code, you need to pay attention to the second part. It will indicate the body type, engine and model. Next will be a variety of information that can indicate both the type of body, chassis, cabin, and the series of the car, the type of brake system, etc. The ninth digit of the code is a verification digit.
The third part also contains useful information. For example, the first character of this part (10th character of the code) indicates the model year, the second - the assembly plant.
Important! Be sure to check the VIN code on the car and in the technical passport when purchasing. If inconsistencies are found, then you should not only refuse the transaction, but also report it to law enforcement agencies.
If you need to find out the engine model, then you can easily use the three described methods (by the number on the engine itself, on the engine compartment plate or by the VIN code). Whatever method you choose, you should use special literature or online services to decipher the symbols yourself.
In addition to being divided into main and auxiliary engines, marine engines are distinguished by the number of strokes that make up the operating cycle. Stroke refers to the working processes in an engine cylinder that occur during one stroke of the piston (up or down). A full operating cycle can be completed in four strokes - four-stroke engines (four piston strokes or two revolutions of the crankshaft) and in two strokes - two-stroke engines (two piston strokes or one revolution of the crankshaft).
Based on the method of forming a mixture of fuel and air necessary for combustion, engines with internal and external mixture formation are distinguished. Internal mixture formation occurs in diesel cylinders due to mixing and evaporation of finely atomized fuel injected by an injector in a high-temperature compressed air environment. External mixture formation is mainly characteristic of engines running on light grades of liquid fuel. These engines use a special device - a carburetor - to form the fuel-air mixture. That's why they are also called carburetor. Four- and two-stroke carburetor engines are often used on small boats, lifeboats, and crew boats as engines for stationary and outboard motors.
On river vessels, engines with a vertical single-row cylinder arrangement and V-shaped engines are used (on motor ships of the “Raketa” and “Meteor” types). Outboard motor cylinders are positioned horizontally.
GOST 4393-74 establishes requirements for the main types and parameters of diesel engines depending on the average effective pressure and rotation speed. These requirements apply to both in-line, V-shaped, and double-row and star-shaped diesel engines. According to this GOST, stationary, marine, diesel locomotive and industrial diesel engines of the specified modifications with a rotation speed from 3000 to 100 rpm, cylinder power from 8 to 4630 e. l. With. and average effective pressure from 4.7 to 20 kgf/cm2 are divided into 24 types.
The direction of rotation of the crankshaft is also considered a classification feature. If you look at the engine from the side of the energy consumer, then for a left-handed (left-hand model) engine the crankshaft will rotate counterclockwise, and for a right-hand model it will rotate clockwise. The passports of engines of foreign brands may indicate the reverse direction of rotation.
There are other classification features. Some of them are reflected in the engine markings.
In accordance with GOST 4393-74, marine, stationary, diesel and industrial engines have letter and digital designations.
The first digit indicates the number of cylinders, the last digits indicate the diameter and, separated by a fraction, the piston stroke in centimeters. The letters between the numbers indicate: H - four-stroke, D - two-stroke, P - reversible (the direction of rotation of the crankshaft changes), C - marine non-reversible (the direction of rotation of the crankshaft does not change, but the direction of rotation of the propeller shaft changes using a special reversible clutch ), the P-engine has a gear transmission from the crankshaft to the propeller shaft, which reduces the speed, the H is a supercharged engine (a fresh air charge is supplied under some excess pressure). There are other designations: DD - two-stroke double-acting engine, K - crosshead, but such engines are not used on river ships. At the end of the brand, after the fractional number, a number may be placed indicating the modification of the engine.
The symbol according to GOST should not be confused with the factory mark (“name”). For example, the 6ChRN 36/45 engine has the factory mark G70; The 3D6 engine according to GOST is designated as 6ChSP 15/18; the M400 engine has a symbol according to GOST 12ChSN 18/20, etc.
ICE is classified according to the following criteria:
1 - by the type of working cycle - by supplying heat to the working fluid at a constant volume, constant pressure and with a mixed supply of fluid (i.e., first at a constant volume, then at a constant gas pressure);
2 - according to the method of implementing the working cycle - four-stroke, in which the cycle is carried out in four consecutive strokes of the piston (for two revolutions of the crankshaft), and two-stroke, in which the cycle is carried out in two consecutive strokes of the piston (for one revolution of the crankshaft);
3 – according to the method of air supply – supercharged and naturally aspirated. In 4-stroke naturally aspirated internal combustion engines, the cylinder is filled with a fresh charge (air or hot mixture) by the suction stroke of the piston; in 2-stroke internal combustion engines, a charge compressor is mechanically driven from the engine. Supercharged internal combustion engines (called combined engines) have a turbocharger that supplies air to the engine at increased pressure;
4 – according to the method of fuel ignition – with compression ignition (diesels) and spark ignition (carburetor and gas);
5 – by type of fuel used – liquid fuel and gas;
6 - according to the method of mixture formation - with internal mixture formation, when the air-fuel mixture is formed inside the cylinder (diesels), and with external mixture formation, when this mixture is prepared before it is fed into the working cylinder. The main methods of internal mixture formation are volumetric, volumetric-film and film;
7 – according to the type of combustion chamber (CC) – with undivided single-cavity, with semi-divided (CC in the piston) and divided CL (pre-chamber, vortex-chamber and air-chamber CL);
8 – by crankshaft rotation frequency n – low-speed with n < 240 мин -1 , среднеоборотные 240 < n < 750 min -1, high speed 750< n < 1500 min -1 and high-speed with n> 1500 min -1 ;
9 – by purpose – main, intended for driving ship propulsors, and auxiliary;
10 - according to the principle of action - simple action (the work cycle is performed in one cylinder cavity), double action (the work cycle is performed in two cylinder cavities - above and below the piston) and with oppositely moving pistons;
11 – according to the design of the crank mechanism (CM) – trunk and crosshead;
12 - according to the arrangement of the cylinders - vertical, horizontal, single-row, double-row, V-shaped, star-shaped.
The main definitions are as follows:
– TDC and BDC, corresponding to the extreme positions of the piston in the cylinder;
– piston stroke, i.e. distance between the extreme positions of the piston;
– volume of the compression (or combustion) chamber corresponding to the volume of the cylinder cavity when the piston is at TDC;
– the working volume of the cylinder, which is described by the piston between the dead centers.
For marking diesel engines produced in the CIS countries, symbols consisting of letters and numbers are adopted: CH – four-stroke; D – two-stroke; DD – two-stroke double action; R – reversible; C – with a reversible clutch; N – supercharged. The absence of the letter K in the marking means the engine is trunk.
The mechanical engineering industry produces a huge number of internal combustion engines, differing in principle of operation, design, purpose, etc. To get acquainted in general terms with the whole variety of existing types of engines, it is advisable to classify them (divide them according to various characteristics). We will give such a division of the internal combustion engine according to the following criteria:
By type of fuel used:
- Gasoline;
- Running on light diesel fuel;
- Operating on heavy residual fuel (such as fuel oil);
- Gas engines (fuel - natural or generator gas);
- Gas-liquid (main fuel - gas, ignition - liquid) and multi-fuel, capable of operating in a wide range of liquid and gaseous fuels.
According to the method of mixture formation:
- With external mixture formation (carburetor and gas engines);
- With internal mixture formation (engines with direct fuel injection and compressor engines).
According to the method of fuel ignition:
- With forced spark ignition (carburetor and gas internal combustion engines);
- With self-ignition (diesels);
- With mixed ignition (calorific engines and so-called “gas diesel engines”, in which the gas is ignited by the self-ignition of a small dose of pilot liquid fuel).
By the nature of heat supply in the operating cycle:
- With heat input at a constant volume (gasoline carburetor engines);
- With heat supply at constant pressure (compressor diesel engines);
- With mixed heat supply (modern diesel engines).
According to the method of carrying out the work cycle:
- 4-stroke and 2-stroke.
By mode of action:
- Simple action (the working cycle is carried out only in the upper cavity of the cylinder);
- Double-acting (the working cycle is carried out both in the upper and lower cavities of the crosshead engine).
According to the method of filling the cylinders:
- Without supercharging (when the air or working mixture pressure in the cylinder is approximately equal to or less than the ambient pressure);
- Supercharged (when air or working mixture is supplied to the cylinder under increased pressure due to compression in the purge and supercharger unit).
According to the design of the combustion chamber:
- Engines with undivided combustion chambers (most marine diesel engines);
- With semi-separated combustion chambers (combustion chamber in the piston) and c) with separated combustion chambers (vortex chamber and pre-chamber engines).
By piston design:
- Tronkovye (when the head bearing is located in the piston);
- Crosshead (head bearing - in the crosshead);
- Rotary engines (the so-called Wankel engines, in which the piston is in the form of a rotating rotor).
By cylinder arrangement:
- In-line execution (most marine diesel engines);
- With oppositely moving pistons (diesels from Doxford, England; engines from the Kharkov Machine-Building Plant ZD-100, etc.);
- V, W, H - shaped;
- Star-shaped;
- Vertical;
- Horizontal, etc.
According to the design of gas exchange organs of 2-stroke internal combustion engines:
- With direct-flow valve purge;
- With direct-flow slot blowing;
- With contour blowing (contour transverse; contour loop or contour combined, including both of these elements).
By purpose:
- Main (working on the propulsion unit directly, through a gearbox, using electric transmission, or generating gas to the main gas turbine - the so-called “free-piston gas generators”;
- Auxiliary (serving to drive auxiliary mechanisms of the power plant).
If possible, change the direction of rotation of the crankshaft:
- Reversible (most main engines);
- Non-reversible (auxiliary engines and some main engines, having a reverse gearbox or operating on an adjustable pitch propeller).
By crankshaft speed:
- Low-speed (with rotation speed n = 60-350 rpm);
- Medium-speed (n = 350-750 rpm) and c) high-speed diesel engines (n = 750-2500 rpm and above).
By average piston speed:
- Low-speed (average speed Cm=4.5-7.0 m/sec);
- Average speed (Cm = 7.0-10 m/sec);
- High-speed (Cm = 10-15 m/sec).
The main characteristics of diesel engines are taken into account in the markings adopted in Russia in accordance with GOST 4393-48. Thus, 4-stroke diesel engines are designated by the letter “Ch”, 2-stroke - “D”, two-stroke double-acting - “DD”, 4-stroke double-acting - “BH”, reversible - “R”, diesel engines with a reversible clutch - “ C", with a built-in gearbox - "P", with supercharging - "N", crosshead diesel engines are designated by the letter "K".
Marine internal combustion engine
In the first place, the engine brand is the number of cylinders, in the last place is the cylinder diameter in the numerator, and the piston stroke in cm in the denominator. In some cases, its modification is indicated at the end of the engine brand. Sometimes the factory engine designation is also used.
Some examples of markings:
- Engine 6DKRN 60/229-10— 6-cylinder, two-stroke, single-action, crosshead, reversible, supercharged, cylinder diameter D=60 cm, piston stroke S=229 cm, 10th modification;
- Engine 64 18/22— 6-cylinder, 4-stroke, trunk, non-reversible, naturally aspirated, cylinder diameter D= 18 cm, piston stroke S=22 cm;
- Engine 42 ChNSP 16/17(factory designation M-503G) - 42 cylinder, 4-stroke, trunk, supercharged, with reversible gear transmission, cylinder diameter D = 16 cm, piston stroke S = 17 cm.
The accepted marking does not allow us to judge all the characteristics of engines. However, this marking gives a more complete picture of the main features of the engine compared to markings adopted in other countries.
