[en] This invention relates to the generation of electrical energy by direct conversion from thermal or electrical energy and notably to liquid metal magnetohydrodynamic convertors. The convertor described in this invention can be successfully used as a source of electrical energy for space vessels, for underwater vessels, for aeronautics and for the generation of electrical energy in thermal or atomic power plants. This liquid metal convertor consists of a heat source, a two phase nozzle, a separator, a steam diffuser and a condenser. These elements are connected together hydraulically in series. The condenser is connected hydraulically to a heat source, a liquid diffuser and a magnetohydrodynamic generator. These elements are interconnected hydraulically to the separator and heat source

[en] The magneto-hydrodynamic converter with liquid metal contains a source of heat, a two phase nozzle, a separator, a liquid diffuser, a liquid metal cooler, a magneto-hydrodynamic generator and means for heating and compressing a liquid coming from the cooler, which are hydraulically connected and in sequence, and which form a closed circuit. A diffuser and a condenser which are hydraulically connected together, are connected between the separator and the means for heating and compressing the liquid metal coming from the cooler. The magneto-hydrodynamic converter with liquid metal can be used to genrate electricity in thermal and nuclear powerstations. (orig.)

[en] Magneto-hydrodynamic generators with liquid metals offer the advantages of high output density and lower working temperatures due to the great electric conductivity of these fluids. On the other hand, it is on principle difficult to accelerate a liquid in a cycle process by adding thermal energy. Based on general thermodynamic considerations, minimum values are deducted for the degrees of reversibility of the cycle processes for liquid-metal MHD systems which may serve as topping stages for conventional power stations. It shows that there are no prospects for applying liquid-metal MHD generators for this purpose. This is also proved by the efficiency calculations for the unary condensation process, if a realistic assessment of the quality grades of the various plant components is carried out. (orig.)

[en] About the characteristic noises occuring in liquid metal-MHD-converters no publication has yet been made. In this study it is tried to give a preliminary description of the development of these noises. The essential causes besides magnetostriction and turbulent-laminar transition of the flow are explained in the following phenomena: With increasing magnetic field, the formation of the flow is more rapid at definite positions in the channel. In this report the changes of profiles due to the effects of finite length are not considered. (orig.)

[en] The quetion of the effect of a liquid layer on the walls of an MHD channel in the case of uniform void fraction distribution in the flow core was first considered several years ago. More recently an analytic solution for high Hartmann numbers was obtained, which led to the conclusion that this layer does not have a significant effect on the efficiency of large generators. This paper postulates an analytic model which makes it possible to estimate the effect of a void fraction nonuniformity, in the presence of the wetting layer on the walls, on the generator performance. 3 refs

[en] Recently 2010, and 2011, two new Medical Linacs, Truebeam STx (Varian Medical Systems, (VMS), USA) were installed in our institution. Among the x-rays beams we can find the flattening filter free, (FFF), an x-rays beam, with the flattening filter removed or shortly unflattened x-rays beams. Their energies: 6xFFF and lOxFFF are distinct from that of ''regular'' or flattening filtered (FF). They are called by VMS, as high intensity beam. A special electron optics was developed for this purpose, and the dose rate achieved for example for the lOxFFF is 400% higher of that of a 10MV x-rays beam (24 Gy/min, against 6 Gy/min). This lead to some parameters differences, like the IAEA-TRS-398 ksat>1.0% found by us and other authors, and some new or different approaches to explain the dosimetric new finds will be discussed: 1- How to determine if the beam is symmetric; 2-ion chamber ksat>1.0%, 3-Have the current RTPs photons model tack into account the high dose rate and the beam shape; 4-Does the linacs model really need the FF?

[en] A liquid-metal magnetohydrodynamic converter is described that is comprised of such hydraulically interconnected components as a heat source, a two-phase nozzle, a separator, a liquid diffuser, a liquid metal cooler, a magnetohydrodynamic generator and a means for heating and delivering liquid metal supplied from the cooler, all of said components being arranged successively so as to form a loop. A steam diffuser and a condenser are interconnected and hydraulically coupled to the separator and the means for heating and delivering liquid metal supplied from the cooler, respectively

[en] For the past several years, Argonne National Laboratory has been active in the development of closed-cycle two-phase-flow MHD power systems. One of the key components in such systems is an effective and efficient gas-liquid separator-diffuser. On the basis of an assessment of present technology, it was decided to study the characteristics of a rotating drum type of separator, and a multitask research and development program was initiated within the overall liquid-metal MHD research program. The first task, now completed, centered on the investigation of single-phase flow (liquid) deposited by a flow nozzle on the inner surface of freely-rotating cylinders or drums of 423 mm and 282 mm diam. The tests were designed to study the recovery of energy in the liquid layer deposited on the drum; the torque transmitted to the drum by the liquid as the result of shear stress between the liquid and the drum surface; the characteristics of the liquid layer; and the effects of drum size, nozzle shape and orientation, and nozzle velocity. The test results showed that a stable liquid film was formed on the drum and that the kinetic energy of the liquid layer was high enough to be potentially useful in two-phase-flow MHD power systems

[en] Short communication

[en] An MHD generator is proposed for direct thermal-to-electric energy conversion. Hot liquid metal is injected into a compressed gas, thus rapidly increasing gas temperature and pressure. The gas expands and imparts the metal kinetic energy which is converted to electric energy. Cold liquid metal is then injected into the expanded gas, which rapidly reduces gas temperature and pressure. This highly increases the efficiency of converting thermal energy to electric energy. (M.S.)