Coaxial pipe, automobile air conditioning system and vehicle

The invention provides a coaxial pipe, an automobile air conditioning system and a vehicle. The coaxial pipe comprises an outer cylinder, a middle cylinder and a top cover, the middle cylinder is located in the outer cylinder, and the top cover is located at one end of the outer cylinder and one end of the middle cylinder; a first heat exchange cavity is defined between the outer cylinder and the middle cylinder; at least two first partition plates are arranged between the outer cylinder and the middle cylinder; the first heat exchange cavity is divided into at least two first sub-exchange cavities by the at least two first partition plates, and the bottoms of the at least two first sub-exchange cavities are communicated; and the top cover is provided with at least one first inlet and at least one first outlet, the first inlet is communicated with one first sub-exchange cavity, the first outlet is communicated with the other first sub-exchange cavity, the first inlet is used for being communicated with an out