refers to the internal combustion engine is an intake pipe of the combustion gas required machine, introduced inside the machine tube. Intake pipe must ensure a sufficient flow area, and a cross section to avoid turning mutation, and the like to improve the surface finish of the pipe, to reduce drag. For this reason, in high performance gasoline engine intake system uses a linear, linearized at the same time, the throttle should be rational design of airway and the intake pipe length, an appropriate arrangement of the regulator chamber volume, in order to achieve high rpm, the purpose of high power.
1 intake pipe intake pipe Category
a different shape, length, shape of the cross sectional area of the intake pipe, designed to represent the demands of this engine. From the shape point of view, it is divided into vertical inlet pipe and the swirl inlet port.
Because of the small vertical inlet intake resistance, high to facilitate the formation of the resonance, to improve intake efficiency, but also facilitate the nozzle arrangement, generally applicable to emphasize the high engine revolution performance; inlet swirls have facilitate the intake eddy current is generated, to improve the mixing of the air and gasoline, low turn facilitates improving the combustion efficiency of the cylinder, is generally applicable to emphasize the low engine revolution performance.
e.g. BMW signs, mounted on the M5V10 is, as it is not employed as Japan Mitsubishi, Honda many sophisticated techniques to enhance the response speed of the engine power output at high speed, etc., instead of using the most direct way to achieve pure performance Int. This ten V10 engine intake pipe is designed with a very short vertical, and are each provided with a throttle valve in the intake pipe, which is to emphasize high to, in response to the most significant design features.
The most obvious and rotating port is a diesel engine, the diesel engine speed is generally not high, emphasis is dynamic performance at low speed, so that the diesel engine are all without exception employed swirl intake airway. Some diesel vehicles also deliberately increase the degree of swirl inlet end, in order to produce the maximum intake swirl, the purpose of improving the degree of mixing of air and fuel.
When the lift speed, the intake air speed and faster frequencies, the inertia of the eddy current generated by such air flow has become a culprit reduced intake efficiency, fuel-air mixture is inconvenient more and faster is drawn into the cylinder. In fact, this is well understood, a swing pipe for air generated by air resistance, is certainly much greater than the pass-through of the pipeline. So this time, vertical inlet conditions more suitable for the needs of the engine.
the shape of the intake nozzle of claim
the intake pipe, the position is not the same nozzle arrangement of two shapes. Vertical intake pipe because simple shapes, small footprint, high intake efficiency, more suitable for direct injection technique (e.g., the GDI Mitsubishi), even as the V10 of the M5, does not use direct injection, can be sprayed nozzle disposed very near the intake valves.
Thus, the engine power and responsiveness can be improved on. But the maneuver inlet, must adopt a more complex spiral, so more space, it is generally injectors are relatively far from the intake valve, fuel-air mixture to go through a longer distance to reach the inner cylinder, which greatly reduced the the response of the engine, and a portion of the mixed gas will be attached to the inner wall of the inlet, the economy will be affected.
2. Effect intake pipe performance
one of the intake pipe is electronically controlled fuel injection type engine and the difference between the maximum engine carburetor structural member. When the EFI engine intake pipe because only air flowing through the intake pipe so during design, dynamic effects should be considered intake pipe (inertia effect and ripple effect) to improve charging efficiency, in addition to consideration of the uniformity of the intake air. Good dynamic matching intake system of the engine so that the torque characteristics of the engine can be greatly improved in a broader speed range. In practice, there is a specific speed region, the use of a specific length of the intake pipe and the ripple effect when inertial effect of intake design, the intake pipe has a variable length.
In the configuration parameters of the intake manifold, the intake air wave effect determined mainly affect structural parameter is intake manifold length. To ensure that the use of ripple effect, should try to ensure that a sufficiently large cavity volume regulator. Intake pipe main parameters affecting the performance of the engine intake summarized as follows:
(1) the diameter of the intake duct intake port, determines the total intake air amount, the throttle valve is determined according to the diameter.
(2) the diameter of the intake manifold, the intake air amount of each cylinder is determined, is determined according to the diameter of the inlet port.
(3) the length of the intake manifold, the influence of dynamic effects. In the optimization calculation in the intake pipe, which is optimized as the target parameters.
(4) chamber volume regulator, fluctuations (resonance) effects. Suitable regulator chamber volume may be utilized not only to improve the charging efficiency fluctuation effects, and can make the pressure regulator chamber environment is relatively stable and provide good conditions for the use of dynamic effects, while eliminating interference between the intake of each cylinder, to improve the uniformity of the intake .
(5) the direction of the intake port, the intake affect the uniformity of the gas. By analysis of various factors, determine the optimal parameters of the target intake pipe optimization calculation for the length of the intake manifold and regulator chamber equivalent diameter.
3. The intake pipe design requirements
includes an intake charge of the intake pipe and the intake manifold. In addition to the requirements of the engine power, but we must also have good economy and emissions performance. On the gasoline engine, the intake pipe must also consider the combustion atomization, evaporation, dispensing, and using a pressure wave and so on. In diesel engines, also called via the intake air flow is formed in the cylinder intake swirl, to improve mixture formation and combustion. These requirements are often contradictory, such as, to obtain high-speed, high-power, gas inlet tube should be selected larger diameter, and is in low economic considerations, the intake pipe should be selected smaller, it must harmonize processing according to the use.