Abstract: A method comprising the steps of: allowing the directions of a magnetic field, an electric current and the liquid metal flow to perpendicularly intersect to one another; and varying at least one of the magnetic field and the electric current in intensity in response to the temperature of the liquid metal. A force acting on the liquid metal flow is increased and decreased by the interaction between the magnetic field and the electric current. An apparatus for performing the method comprising material varying in electric property with the temperature of the liquid metal. The material is installed in at least one of a path of the magnetic field, a path of the electric current and means for generating the magnetic field. Variation of the electric property of the material allows one of the magnetic field and the electric current to be automatically increased or decreased in intensity in response to the temperature of the liquid metal, so that the force acting on the liquid metal flow is controlled.

Abstract: The present invention includes a method of air-conditioning which forms, in a space to be air-conditioned, a plurality of circulating flows of air respectively blown through air outlets of an air-conditioning system disposed at predetermined positions within this space and which successively repeats two steps: a first step of changing the effective range of at least one of the circulating flows; and a second step of returning that circulating flow or flows as effected in the first step to the effective range thereof which obtained before the first step, and an air-conditioning system for carrying out this method, which forms, in a space to be air-conditioned, a plurality of circulating flows of air respectively blown through air outlets of an air-conditioning system disposed at predetermined positions within the space and which comprises: a means for changing the effective range of at least one of the circulating flows and returning that circulating flow or flows as changed to the effective range thereof whic

Abstract: A heat exchanger has upper and lower plenums which communicate with each other via heat transfer tubes. A downwardly-extending tube used to introduce secondary sodium coolant into the lower plenum extends among the heat transfer tubes and is fastened to the lower tube plate to communicate with the lower plenum. The downwardly-extending tube is stretched through the lower plenum in the axial direction thereof to contact at its lower end a bottom surface of the heat exchanger body. A plurality of openings are provided in a wall of the portion of the downwardly-extending tube which is in the lower plenum.Primary sodium coolant of a high temperature flows into the heat exchanger body from the portion thereof which is below an upper tube plate, and flows out of the heat exchanger body from the portion thereof which is above the lower tube plate.