A manifold for a heat exchanger and a heat exchanger wherein the manifold includes: a pipe having an end portion; an end cover disposed at the end portion of the pipe and closing the end portion of the pipe to define an inner cavity in the pipe; and a discharge passage including: a first end opening into the inner cavity of the pipe, and a second end located at or adjacent to an end of the manifold and positioned at an outer peripheral surface of the manifold. The first end of the discharge passage is located on a side of the end cover facing the inner cavity of the pipe. According to embodiments of the disclosure, the stacking mounting of the heat exchangers in the axial direction of the manifold and the mounting of the heat exchanger with the end cover of the manifold contacting the ground can be achieved.

An exothermal vaporizer is provided. The exothermal vaporizer has a body including an air and vapor mix port, a fluid inlet port in communication with a reservoir, an air inlet, and a wicking material. A mouthpiece is coupled to the body and a temperature indicating cap is removable from the body. A counter flow design exothermal vaporizer, a modular exothermal vaporizer, and a vaporizer which is adjustable to modulate and/or regulate the flow ratio of dilution air and produced vapor are also disclosed.

A water block structure with upgraded heat dissipation efficiency includes vertically stacked top cover, intermediate plate and heat sink. The intermediate plate and the heat sink together define a heat exchange chamber communicable with first and second passages on the intermediate plate and internally provided with fins. The fins are transversely extended and spaced to form a transverse flow passage between any two adjacent fins. A middle portion of the transverse flow passages corresponding to the first passage; and a peripheral flow passage communicable with end portions of the transverse flow passages and located corresponding to the second passages is formed around the fins. A working fluid flows downward into the heat exchange chamber via the first passage to flow through the transverse flow passages and the peripheral flow passage while sufficiently contact with all the fins before flowing upward via the second passages to leave the water block structure.