The University of Tokyo

Nobuhide Kasagi

Yuji Suzuki

Yasuhiro Arakawa

Kenichi Morimoto

Naoki Shikazono

Yoshinori Suzue

A heat exchanger has multiple laminated fins. Each finhas multiple topsand multiple bottomsarranged to have a preset acute angle &#x3b3; (for example, 30 degrees) to an air flow line at an air inlet and to make an air flow in a cavity region behind each of multiple heat transfer tubestoin an air flow direction at an air outlet. This design of the finsproduces effective secondary flows of the air to improve the heat transfer efficiency and makes an additional contribution to heat exchange, due to the air flow in the cavity region behind each of the heat transfer tubestoin the air flow direction. This arrangement effectively prevents separation of the air flow and a local speed increase of the air flow, while improving the overall heat exchange efficiency by production of the effective secondary flows of the air.

Fin structure for fin tube heat exchanger

There is provided an electrostatic induction conversion device which is small, has high conversion efficiency between electric energy and kinetic energy, and can prevent degradation of an electret. The electret is formed by injecting an electric charge into the vicinity of the surface of an insulating material, is disposed between two conductors, and is constructed so that it moves relatively to at least one of the conductors opposite to the electret and converts between electric energy and kinetic energy. As the insulating material forming the electret, it is preferable to use a polymer having a fluorine-containing aliphatic cyclic structure.

Growing community of inventors

Tokyo, Japan

Nobuhide Kasagi