Flash evaporator, air supplementing and enthalpy increasing system and air conditioning equipment

The invention provides a flash evaporator, an air supplementing and enthalpy increasing system and air conditioning equipment, relates to the technical field of air conditioners, and solves the technical problems that in the prior art, a flash evaporator and a gas-liquid separator serve as two independent pressure containers, due to the fact that the size is large, after pipelines and valves matched with the flash evaporator and the gas-liquid separator are added, the pipeline space is more compact, and the cost is low. Therefore, the selected outdoor unit shell is larger, and the configuration cost is increased. A separation structure is arranged in a shell of the flash evaporator, a cavity in the shell is divided into a flash evaporation cavity and a separation cavity which are not communicated with each other through the separation structure, the separation cavity has a gas-liquid separation function, sucked gas enters the separation cavity from a sucked gas inlet pipe, and liquid refrigerants carried in t