No abstract available

[en] In the case of large capacity steam turbines the conventional nozzle group control is, for mechanical and thermodynamic reasons, diminishing more and more in importance in favour of variable pressure control. A design for constant-pressure operation as an alternative to nozzle group control is described; this demonstrates a series of important advantages compared with the latter. (orig.)

[en] A method and apparatus is described for protecting fuel rods in a nuclear reactor core under conditions of a major break in the coolant inlet piping connected to the reactor inlet nozzle. A multi-venturi protector which includes multiple parallel disposed venturis is mounted in the inlet nozzle. The characteristics of the venturi protector are such that coolant flow through the protector into the reactor is unimpeded, but reverse flow through the protector is restricted when a break occurs in the inlet piping. The resistance offered to such reverse flow permits reactor coolant and emergency core coolant to remain in contact with the reactor core for a time sufficient to allow the fuel rods to decrease in temperature to a low safe level. (author)

[en] In order to mitigate the cavitations of the axial flow pump and improve the flow state of the main impeller, this paper gives a primary study on the design of the front guide impeller of the axial flow pump and its configuration. This paper address the determination and analysis of the parameters for the design of the front guide impeller, the determination of the guide impeller dimension and the calculation and diagraph of the shape of the guide impeller vane and so on. The guide impeller is designed to effectively reduce the water vibration and noise of the axial flow pump

[en] Short communication

[en] A fluidized solids control valve is disclosed that is particularly well adapted for use with a flow of coal or char that includes both large particles and fines. The particles may or may not be fluidized at various times during the operation. The valve includes a tubular body that terminates in a valve seat covered by a normally closed closure plate. The valve body at the seat and the closure plate is provided with aligned longitudinal slots that receive a pivotally supported key plate. The key plate is positionable by an operator in inserted, intermediate and retracted positions respecting the longitudinal slot in the valve body. The key plate normally closes the slot within the closure plate but is shaped and aligned obliquely to the longitudinal slot within the valve body to provide progressively increasing slot openings between the inserted and retracted positions. Transfer members are provided between the operator, key plate and closure plate to move the closure plate into an open position only when the key plate is retracted from the longitudinal slot within the valve body

[en] This paper presents experimental and model-predicted pressure-flow characteristics of axisymmetric venturi-like reverse-flow diverters (RFDs), the key component of fluid pumping systems utilized for the transport of hazardous fluids. The effects of several key geometric parameters, operating conditions, and fluid properties on the performance of the RFD are presented and compared to model predictions. The results indicate good agreement between data and theory over a large portion of the range of variables studied. Cavitation is observed to be the primary factor in limiting the performance of the RFD at small values of load impedances

[en] The electric circuit is given of an automatic device for periodically filling a cryostat with liquid He. This device delivers helium from standard transport vessels, by means of a gas inflator. The inflator is controlled by an automatic system with superconducting wires stretched vertically for monitoring the liquid level. The system can work with the wire length from 150 to 900 mm, giving the flow rate of liquid He up to 80 1/h. at an inflation pressure to 0.3 kg/cm², and with a precision of maintenance of the minimum level +-2 mm. Prolonged use of the system with various types of cryostat, including the constant transfer of liquid He have shown the high reliability of design, simplicity of maintenance and convenience in operation

[en] Elution is done by means of an evacuated septum flask. For dosing, a needle with its tip projecting into the elution material container is used, where the depth of penetration can be selected. The setting of the needle is adjustable with reference to its axis, so that the volume of the eluate can be decided. (DG)

[en] A magnetic fluid flow diverter, that avoids the need to penetrate pipework by operating spindles of valves or vanes which increase the risk of an integrity breach, is given. (UK)