Shell-and-tube heat exchanger and air conditioning system

A shell-and-tube heat exchanger, comprising:

• a shell provided with a liquid inlet and an vapor outlet, the vapor outlet being disposed at an upper portion of the shell;
• a heat exchange tube bundle disposed in the shell in an axial direction of the shell;
• and
• a baffle assembly disposed at an entrance of the vapor outlet and having a baffle capable of adjusting a blocking area;
• wherein the baffle assembly comprises:
• a bracket, a first end of which is fixed to the vapor outlet, and a second end of which extends from the vapor outlet toward the internal portion of the heat exchanger;
• a baffle, which is connected to the second end of the bracket and driven to change the blocking area;
• and
• a connecting rod, two ends of which are connected to the bracket and the baffle respectively, wherein a reciprocating movement of the connecting rod with respect to the bracket causes a rotational movement of the baffle with respect to the bracket.