What is the difference between turbocharging and mechanical supercharging of an engine?

The supercharger --- to increase the amount of fuel and air per unit volume of the engine, so as to achieve higher power. Boosting here is all about increasing the air intake of the engine.

Mechanical supercharging: that is, the engine drives a fan mounted in the intake pipe through the belt; Forced blowing increases the air intake of the engine.

Advantages: The engine turns the fan, and the low-speed boosting effect is good.

Disadvantages: Lose part of the engine's energy, high-speed supercharging effect is not obvious.

Turbocharging: It is to use the exhaust energy of the car to drive a turbine to rotate, and drive the fan installed in the intake pipe at the other end to rotate the air to increase the air intake.

Advantages: the use of exhaust energy, no loss of engine energy, when the engine is at high speed, the exhaust energy is large, and the pressurization effect is good.

Disadvantages: When the engine is at low speed, the exhaust gas energy is small, and the supercharging effect is not obvious. High maintenance costs.

- Hope it helps.

It should be said that turbocharging is a device that increases the amount of air intake by pushing the intake air by exhaust, rather than absorbing the exhaust gas and reusing it, which is called the exhaust gas recirculation system. The advantages of turbocharging are: the output torque is strong; The disadvantages are:

Because the torque is increased by the exhaust to push the intake, it cannot produce a strong torque in a moment when accelerating suddenly, but slowly outputs high torque when the speed is slowly increased (in response to this defect, the twin turbo has been designed to solve its shortcomings). Mechanical supercharging is the use of the mechanical mechanism on the engine to directly drive the supercharging device, the speed of the supercharging system is proportional to the speed of the engine, its advantages are: the supercharging speed is fast, there is no lag disadvantages; The disadvantages are:

The output torque is limited by the rotational speed and does not provide a high torque boost value.

Mechanical supercharging is to rely on a mechanical supercharging group, relying on the engine to provide it with power to make the supercharging group work, mechanical supercharging mostly works at low speed, mechanical supercharging group is more precise, maintenance is more expensive. The turbine relies on the exhaust gas of the engine to push the turbine blades to rotate, forcing the air into the inlet tract to suck in more air.

The turbocharger is generally used to blow the turbine to rotate with the exhaust gas after combustion, and then the turbine drives the compressor impeller on the coaxial to rotate to compress the air.

Mechanical pressurization, also known as forced air intake, increases the air intake volume by compressing the air volume. The mechanical boost power is a little larger.

1. The disadvantages are different.

Supercharging: One of the most obvious turbocharging technologies is the "hysteresis response", that is, because the inertia of the impeller reacts slowly to sudden changes in the throttle, even after the modified reaction time is seconds, so that the engine delay increases or decreases the output power. So if you accelerate sharply, you will feel like the engine is not working.

But with the advancement of technology, the turbo delay has improved to some extent.

Turbocharged: The acceleration effect is not very noticeable, and it is not much different from the naturally aspirated engine. It will lose part of the kinetic energy of the engine, and the supercharging is driven by the belt, and in the final analysis, the driving force is still the engine. At high speeds, a lot of friction will be generated, which will affect the increase of speed and make a lot of noise.

2. The structure is different.

Supercharger: The supercharger is connected with the engine crankshaft pulley by belt, and the internal blades of the supercharger are driven by the engine speed to generate pressurized air into the engine intake manifold, and the overall structure is quite simple, and the operating temperature is 70 -100.

Turbocharging: The turbine chamber air intake is connected to the exhaust manifold, and the exhaust port is connected to the exhaust pipe; The supercharger intake is connected to the air cleaner duct, and the exhaust port is connected to the intake manifold. The turbine and impeller are housed in the turbine chamber and the supercharger respectively, and they are rigidly connected coaxially.

Supercharging. Turbocharged.

3. The principle is different.

Mechanical supercharging: The power of the engine itself is used to drive a compressor to supercharge. The supercharger will consume the power of the engine, its speed changes with the engine speed, there will be no supercharger lag, the engine is excellent when running at low speeds, but it is limited by the engine speed, and the engine will be under-pressurized at high speeds.

Turbocharging: The exhaust gas generated by the engine is used to push the turbofan in the exhaust pipe to drive the turbofan in the intake pipe to rotate, and the engine is indirectly supercharged without consuming the power of the engine. The turbocharger has an extremely high rotational speed and the increased pressure is several times higher than that of a supercharger.

However, due to the inertia of the turbofan and the considerable resistance of the intermediate bearing, the turbofan speed will not increase at the same time when the exhaust gas suddenly increases, which is the turbo hysteresis.

1. The dynamics are different.

Supercharging can get good power at low revs, while turbocharging will lag.

2. Turbocharging is different.

The power gain at high revs of mechanical autoclaving is limited, while turbocharging does not.

3. The maintenance cost is different.

Both the manufacturing and maintenance costs of superchargers are higher than those of turbochargers.

4. The power is different.

Mechanical supercharging also consumes engine power, while turbocharging does not.

Turbocharging uses the exhaust emissions from the engine to drive the compressor. The first superchargers were all supercharged, which was called supercharge when it was first invented, and later after the invention of turbocharging, in order to distinguish between the two. Originally, turbochargers were called turbo superchargers, and superchargers were called mechanical superchargers, and over time, the two were simplified to turbocharger and supercharger respectively.

The turbocharging principle uses the exhaust gas discharged when the engine is running, and uses the exhaust gas to rotate the exhaust side rotor in the turbocharger, and the exhaust side rotor and the intake side rotor (compressor) are coaxial different chambers, when the turbine rotor reaches a certain speed (about 12000rpm), it drives the compressor on the other side, so that the compressor rotor introduces foreign fresh air, and is compressed and poured into the intake manifold. Therefore the air intake of the turbo car is an unnatural way and is passed"Suck it in and compress it again"So the air pressure is greater than the atmospheric pressure. Turbocharging is the operation of the bearing at very high speeds, and the subsequent high temperature removal or excessive pressure relief is the key. At present, the commonly used is the introduction of engine oil to lubricate and cool the bearing, and there are also water-cooled types.

However, excessive supercharging will cause damage to the compression stroke and power (**) stroke of the engine, so there is a mechanical use of air pressure as a switch or an electronic computer to directly control the action of releasing pressure.

The driving force of the supercharger compressor comes from the engine crankshaft, which is generally connected to the crankshaft pulley by belt, and indirectly drives the supercharger with the torque of the crankshaft to achieve the purpose of pressurization. According to different structures, there have been many types of supercharging, including vane, roots, wankle and other types, and piston movement was first considered a kind of supercharging, and today, Lu's supercharger is the most widely used, and it is a popular modification. Lu's supercharger has two types of double-leaf and three-leaf rotor, at present the two-leaf rotor is more common, its structure is to install two cocoon-shaped rotors in the oval shell, the rotor retains a very small gap and is not directly connected, through the helical gear linkage, one of the rotors is connected with the driving pulley, the pulley of the rotor shaft is equipped with an electromagnetic clutch, when the pressurization is not needed, the clutch is released to stop the pressurization, and the clutch is controlled by the computer to achieve the purpose of fuel saving.

The characteristics of supercharging, in addition to the supercharging can be obtained at low speed, the power output of the supercharger is also in a certain proportion to the crankshaft speed, that is, the throttle response of the supercharged engine is enhanced with the increase of the speed, so the operation of the supercharged engine is very similar to the natural gas, but it can have greater horsepower and torque.

In general, it is to decide the advantages and disadvantages of the two booster methods according to your needs.

Mechanical supercharging, mainly in the face of large displacement engine, the engine has enough torque to drive the supercharger, the same needs the main output section of the engine in the low speed section below 4500rpm, we all know that the supercharger will become the load of the engine at high speed, and the power increase brought by the supercharger is not as good as the power consumed by the supercharger, then it is beyond the means. However, because the supercharger can be started at the same time when the engine is started when the camshaft is pushed to rotate, because the supercharger is directly linked to the engine by a steel belt, there will be no hysteresis of turbocharging.

Turbocharging, mainly for small displacement engines, requires the engine transmission part (mostly refers to the camshaft part) to be able to cope with the high temperature caused by high-speed rotation, because the output section of the turbine is after 4500rpm, this number is the usual value, that is to say, when the engine speed is faster, the better the supercharging effect, because the turbine is driven by exhaust gas, and the faster the speed, the faster the work is done, and then the frequency and pressure of exhaust gas discharge are greater. There are two disadvantages of the turbine, one is that the turbine advantage is not obvious at low rpm, and the second is the turbo lag (which will not be described here).

In fact, there is no need to choose between mechanical supercharging and turbocharging, Volkswagen has achieved the perfect combination of two supercharging methods, DoubleCharge or Dual Charge technology, which is different from Mercedes-Benz's Bicharge

Tandem turbo technology, as well as other manufacturers such as the universal TwinCharge side-by-side turbo, DoubleCharge uses complex electronic and mechanical conversion components to achieve supercharging and turbocharging interchange at 4500rpm exchange points, which means that Volkswagen can make two supercharging systems work for the engine at the same time.

Mechanical supercharging is the use of the power of the engine itself to drive a compressor to pressurize. Therefore, the characteristic is that the transmission is direct, and the car can work when it starts. But it 4 loses power more obviously at high speeds.

Turbocharging, on the other hand, uses the exhaust gas power generated by the engine to push the fan for indirect supercharging. Therefore, the characteristic is that it cannot be directly pressurized, and the exhaust gas discharged at low speed cannot push the fan, and it can only be above a certain speed. This gives rise to the so-called turbo hysteresis, which is also a common problem with turbocharging.

However, at high speeds, the power boost is noticeable. Half of the small displacements are turbocharged, and the large displacements are more mechanically supercharged.

However, now that technology is developed, some shortcomings have been overcome. There are also TSI like Volkswagen, turbomachinery together, complementing each other's strengths. This is also Volkswagen's trump card technology.

Dude, word by word, typed ......

Turbo increase is dependent on the exhaust gas of the engine, push a propeller, drive the compressor supercharging mechanical supercharging is to use an electric motor or directly from the engine shaft to take power, drive the compressor supercharging surface, turbocharging does not use a special motor to drive, nor does it use another transmission system, but also uses exhaust gases, the best.

However, turbocharging is done with exhaust gases, that is, if the engine exhaust gas is not much at low speed, the supercharging effect is not good, but at this time it is the time when supercharging is most needed, at high speed, supercharging is good, but it also increases the exhaust resistance, and it will also consume a little more fuel.

It doesn't matter if the supercharger is supercharged, it can be better matched with the engine, and the effect is better, but the fuel consumption is a little higher than that of turbocharging, so the high-end cars are supercharged, or mechanical-turbocharged dual supercharging, low-speed with machinery, high-speed with turbo.

The supercharged supercharged fan power** is the engine's output shaft.

Turbocharging is the kinetic energy of exhaust gases.

In terms of performance, the mechanical supercharging effect is better, there is no time lag, but the fuel consumption is large, and the turbo has a time lag, that is, turbo lag, but the fuel consumption is small. At the same power, the fuel consumption is even smaller than that of the NA.

Supercharging can significantly increase the engine's low-rev torque without turbo lag, and the technology is simple and reliable, but because the supercharging is powered by the engine output shaft, the economy does not have many advantages over naturally aspirated of the same power, and the higher the rpm, the more power the supercharger consumes, thus limiting the engine's top speed and maximum power.

Turbocharging because the power of the supercharger comes from the thermal energy of the exhaust gas, the economy is better than the natural aspiration of the same power, and the supercharger does not burden the engine, the maximum power can be done very high, but because the speed of the turbo cannot keep up with the change of throttle due to inertia, even if the technical improvements such as twin turbo or even variable geometry turbine are adopted, the turbo hysteresis is still difficult to completely eliminate, and usually the higher the supercharger value, the more obvious the hysteresis. However, with the introduction of electric motors and hybrids, relying on the active compensation of the electric motor and engine energy** like the McLaren P1, there is almost no throttle lag even when the boost value is high enough to squeeze 737 horsepower. However, the turbocharging structure is complex, the process requirements are very high, and the reliability is relatively inferior to that of mechanical supercharging.