Abstract: A heat exchanger comprises a shell having a first inlet and a first outlet for a first fluid (H) and a second inlet and a second outlet for a second fluid (C), and a screw element. The screw element has a core and first and second nested helical flights mounted to the core. The helical flights define first and second helical fluid passages along the shell. The first fluid passage is in fluid communication with the first inlet and the first outlet and the second fluid passage is in fluid communication with the second inlet and the second outlet. The heat exchanger further comprises a plurality of tubes mounted between adjacent turns of the first and second helical flights and extending across the fluid flow passage formed between the helical flights for conducting the first and or second fluid.

Abstract: In a small-sized fluid heat exchanging apparatus that heats or cools a huge amount of gas or liquid, a structure makes fluid having a high flow speed impinge perpendicularly against a wall. A flow passage is divided into a high-speed flow passage and a low-speed flow passage, and the high-speed flow passage and the low-speed flow passage are arranged so as to intersect perpendicularly with each other, according to guidelines for the shape of the flow passage. A flow passage designed according to the guidelines provides highly-efficient heat exchange.

Abstract: A heat transfer system comprises a plurality of cells, a plurality of heating elements, and a controller for independently controlling the plurality of heating elements. The heat transfer system is capable of maintaining a fluid temperature within a predetermined range. A second pump pumps fluid through a heat exchanger in operative relationship with the blower upon a call for heat.