All kinds of air compressors（一）
If the fuel cell reactor is the "big heart" of the fuel cell power system, then the air compressor is the "strong lung", and the high performance output of the fuel cell system requires a strong "heart-lung function". It can be described as such, at present air compressor is the most core of the key components in addition to fuel cell reactor in China.
Although the design method of the air compressor used in fuel cell is similar to that of the traditional internal combustion engine supercharger, there are great differences in the operating environment, working range and requirements.The air compressor for fuel cell needs to be oil-free, low noise, low cost, miniaturized, wide working range and fast dynamic response.To some extent, the fuel cell air compressor represents the highest level of the air compressor industry, covering a wide range of disciplines such as aerodynamics, heat transfer, fluid mechanics, machinery, electronics, materials, electrical control and NVH.
The following will start from the centrifugal air compressor, in turn to introduce each type of air compressor.
Centrifugal air compressor has the best overall effect in terms of power density, efficiency and noise, and is regarded as one of the most promising air compression methods in the future.The main working principle is to use the impeller to do work on the gas, in the impeller and diffuser's flow passage, the use of centrifugal boost and downspeed diffuser action, mechanical energy into the gas pressure energy.Although the relevant data show that from the current domestic and foreign fuel cell air compressor development direction, centrifugal air compressor will be the future of the mainstream direction.
Centrifugal air compressor also has some disadvantages, such as not suitable for gas flow is too small and the pressure ratio is too high occasions, narrow work area, poor economy, low efficiency.
Screw type air compressor can be divided into single screw type and double screw type. A screw air compressor is equipped with a pair of spiral Yin and Yang rotors meshing with each other in the cylinder. Both rotors have several concave teeth and rotate in reverse. The main rotor is also known as the positive rotor or convex rotor, driven by the engine or motor, the other rotor is called the negative rotor or concave rotor, driven by the main rotor end and the concave rotor end synchronous gear. Theoretically, there is no metal contact during the drive.