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Now many vehicles are equipped with two types of engines, turbocharged and naturally aspirated, for consumers to choose from. Many consumers are hesitant when choosing, and don't know which type to choose.
Naturally aspirated engines and turbocharged engines, that is, what people usually call with "T" and without "T". The one with "T" is a turbocharged engine, and the one with "L" is a naturally aspirated engine. So what are the advantages of these two engines?
First, let's talk about the working principle of the engine. Where does the engine power come from? First, it takes in air, injects fuel, and then compresses and works to generate power. How can we generate more power? It's very simple to increase the intake and injection volume on the original basis, so as to improve the power of the engine and generate more horsepower. It's easy to say, but it's not easy to do. Turbocharging is the product of this idea. What is self-priming? What is turbocharging? Maybe for some non-car owners or car novices, they almost don't know what is naturally aspirated and what is turbocharged? First of all, the so-called natural aspiration is a form in which atmospheric pressure presses air into the combustion chamber without passing through any supercharger. To put it simply, when a car is working, its intake pipe is equivalent to a vacuum tube, and the air pressure is pressed into the intake manifold by atmospheric pressure, just like the "inhalation" when we breathe normally! So what is turbocharging? Turbocharging is a technology that uses the exhaust gas generated by the operation of an internal combustion engine to drive an air compressor. From a structural point of view, the difference between turbocharging and self-priming is that there is an additional "air compressor", which increases the intake volume by compressing air, making turbocharging more powerful than naturally aspirated engines. This is like having a larger "lung capacity", and people with large lung capacity will certainly be more energetic when exercising.
What are the advantages and disadvantages of naturally aspirated engines and turbocharged engines?
The structure of a naturally aspirated engine is relatively simple because it has been developed for a long time, so the structure is also relatively complete. For turbocharged engines, its advantages are also more obvious, and of course the disadvantages are more prominent.
1. From the perspective of service life and maintenance cost, naturally aspirated engines are better, because turbochargers work at high temperatures for a long time. Under normal working conditions, they can be fully cooled. However, after stopping and shutting down the engine, the turbine blades run at high speed under the drive of inertia, causing damage to the bearings, which will reduce the service life of the turbine in the long run. So in theory, the life of turbochargers is not as long as that of naturally aspirated engines.
2. From the perspective of technical reliability, naturally aspirated engines have been relatively complete after a long period of technical accumulation. The technology is very reliable and the quality is stable. The oil quality requirements are not as high as those of turbochargers. The structure and maintenance of naturally aspirated engines are relatively simple, and they have more advantages than turbocharged engines in terms of smoothness, durability, stability and safety. It can be said that turbocharged engines are not a very mature technology, and the failure rate is high, such as acceleration hysteresis, service life and other problems. Compared with naturally aspirated engines, turbo engines have higher requirements for maintenance. They must be maintained on time and high-quality engine oil must be used. The cost of later maintenance is generally high.
3. From the perspective of power, the acceleration ability of a naturally aspirated engine is relatively smooth and slow, not as exciting as a turbocharged engine. Turbochargers can make the car more powerful, and it is better to run on the highway frequently. The acceleration is very fast, but it is difficult to control it freely. The acceleration of a naturally aspirated engine is relatively smooth, the speed is slowly increased, and it is easier to control. The noise is also relatively low.
4. Another thing is fuel consumption. The turbocharged engine has good power performance, but you have to use oil to support it. The fuel consumption is generally much higher than that of a naturally aspirated engine. You can't want the horse to run and not eat grass.
How to choose?
If you drive gently, live at home, don't want the car to have too many minor problems, buy a car and want to drive it for ten or eight years, don't plan to change it in a short time, and don't want to spend too much money on later maintenance, then choose naturally aspirated. And if you live at home, choose a five-seater car with a 1.6L or less 1.6L, the basic power is completely enough.
The following is the proportional relationship between the three
Boost Pressure, Manifold Absolute Pressure (MAP) and Atmospheric Pressure are different concepts that describe the pressure in the engine intake system. The differences between them are mainly reflected in the measurement location, reference base and application scenario. The following is a detailed description:
1. Atmospheric Pressure
Definition: Atmospheric pressure is the pressure exerted by air on a unit area on the surface of the earth, usually about 101.3 kPa (1 bar or 14.7 psi) at sea level.
Features:
It is the base pressure of the natural environment.
It decreases with increasing altitude (for example, the atmospheric pressure is about 70 kPa at an altitude of 3,000 meters).
Application:
As a reference base for the engine intake system.
The intake pressure of a naturally aspirated engine is close to atmospheric pressure.
2. Manifold Absolute Pressure (MAP)
Definition: Manifold absolute pressure refers to the air pressure in the engine intake manifold, measured with absolute vacuum as the reference (0 kPa).
Features:
Includes the combined effect of atmospheric pressure and boost (or negative pressure).
In naturally aspirated engines, MAP is usually lower than atmospheric pressure (due to negative pressure caused by intake resistance).
In turbocharged or supercharged engines, MAP may be higher than atmospheric pressure (due to boost).
Application:
Used by the engine control unit (ECU) to calculate the intake volume, adjust fuel injection and ignition timing.
It is an important parameter to measure the engine intake efficiency.
3. Boost Pressure
Definition: Boost refers to the additional pressure generated in the intake manifold by the turbocharger or supercharger system, usually expressed as the part above atmospheric pressure.
Features:
Boost = Manifold Absolute Pressure (MAP) - Atmospheric Pressure.
For example, if MAP is 150 kPa and atmospheric pressure is 100 kPa, the boost pressure is 50 kPa (or 0.5 bar).
The higher the boost pressure, the greater the density of the air entering the cylinder, and the stronger the engine power output.
Application:
Used to evaluate the working effect of the boost system.
High-performance engines usually have higher boost pressure values (such as above 1.0 bar).
4. The relationship between the three
Formula: Manifold Absolute Pressure (MAP) = Atmospheric Pressure + Boost Pressure
Example:
If the atmospheric pressure is 100 kPa and the boost pressure is 50 kPa, the MAP is 150 kPa.
If the atmospheric pressure is 80 kPa (high altitude area) and the boost pressure is 50 kPa, the MAP is 130 kPa.
5. Summary of differences
Parameter Definition Reference Typical value Application scenario
Atmospheric pressure Ambient air pressure Absolute vacuum (0 kPa) Sea level is about 101.3 kPa Reference for naturally aspirated engines
Manifold absolute pressure Absolute pressure in the intake manifold Absolute vacuum (0 kPa) Naturally aspirated: <100 kPa; Boost: >100 kPa Engine control (fuel injection, ignition timing)
Boost Pressure in the intake manifold above atmospheric pressure Atmospheric pressure Turbocharged: 50-150 kPa Evaluate boost system performance
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