Steam generator

A steam generator, comprising:

• a heat exchanger, assembled by several heat exchanging subassemblies with the same structure, each heat exchanging subassembly includes a spiral heat transmission pipe bundle including a plurality of spiral heat transmission pipes, a central cylinder and a sleeve, the spiral heat transmission pipes having different radii are concentrically and spirally arranged in an annular space between the central cylinder and the sleeve, to form one or more concentric heat exchanging pillar surfaces;
• a liquid header, one end of which is connected with a main water feeding pipe, and the other end of which is connected an end of each heat exchanging subassembly;
• and
• a steam header, one end of which is connected with a main steam pipe, and the other end of which is connected with an opposing end of each heat exchanging subassembly;
• each spiral heat transmission pipe including a radius of curvature configured to receive a sensing probe for determining a volume and a surface area of each transmission pipe such that the sensing probe can reach the transmission pipes and pass through all the way,
• wherein inside a part of the connection with the liquid header, each spiral heat transmission pipe is installed with a fixed orifice plate and a detachable orifice plate, the fixed orifice plate being used for ensuring the stability of the flowing of two-phase fluid in the spiral heat transmission pipe and distributing the resistance of each spiral heat transmission pipe, and when one spiral heat transmission pipe is out of work, the detachable orifice plate is used for realizing the reallocation of flow in the spiral pipe by detaching the detachable orifice late of other spiral heat transmission pipes on the spiral pillar surfaces on which the spiral heat transmission pipe that is out of work is located.