What's the difference between straight tube, M tube and internal back pressure tube in muffler?

There are many kinds of automobile exhaust pipes, mainly including straight exhaust pipe, G pipe, S pipe (internal back pressure pipe), H pipe and M pipe. They are obviously different in structural design, exhaust sound and power loss.

1, straight exhaust drum, that is, from the exhaust manifold, remove the catalyst section and tail exhaust, and directly discharge the exhaust gas into the air. This kind of exhaust effect is better, which is very suitable for running high speed and track for a long time. The sound is about 100 dB, and the vibration of the car is obvious during operation. It consumes more fuel and energy.

2. Back pressure drum can improve the torque at middle and low speed, start faster, have more obvious dynamic response, save more fuel and be more suitable for urban use. However, when driving at high speed, the exhaust is not smooth enough, which will affect the horsepower, so the straight-out large-diameter exhaust pipe can be used to improve the high-speed horsepower.

3. M drum-The back pressure design can be changed, and the back pressure can be adjusted according to the speed. When the engine is at low speed, the gas flow speed is slow. By adjusting the speed, a small landing space and suction can be generated. The back pressure of the exhaust gas stored per unit time is large. When the engine runs at high speed, a great vacuum will be generated. When the engine is at a high speed, it will emit more exhaust gas. It will also increase torque and horsepower.

Extended data:

Application of microperforated plate theory in the design of blowout preventer muffler;

There are many kinds of silencers designed and manufactured by using the acoustic structure of micro-perforated plate, and the main type is jet resistance silencer. This muffler is made of stainless steel perforated plate. Because the nine silencers are used in petrochemical plants, the air is corrosive, and the sound absorption material filled in the air layer behind the perforated plate is corrosion-resistant metal soft silk cloth.

Based on the resistive sound absorption principle of sound-absorbing materials, noise reduction and noise elimination can be further realized, with high sound absorption coefficient, wide absorption frequency band, small pressure loss, low airflow regeneration noise and easy control.

References:

Baidu encyclopedia-exhaust muffler