Abstract: The object of the invention is to create an internal combustion engine, connected to two exhaust-gas turbochargers, with reduced flow losses and an improved efficiency which is particularly suitable for relatively high boosting. According to the invention this is achieved by virtue of the fact that in an apparatus in accordance with the preamble of claim 1, the two exhaust-gas turbochargers (1,1') are arranged offset sideways relative to one another. The diffuser outlets (5,5') of the radial turbines (2,2') are arranged point-symmetrically with respect to the center (8) of the central wall (6). The lateral spacing of the axes (9,9') of the radial turbines (2,2') from the wall (10,10') of the turbine outflow casing (3) on the outflow side (11,11') of the radial turbines (2,2') is designed so as to be greater than their lateral spacing from the other wall (12,12') in each case.

Abstract: A method and a circuit arrangement having a device for measuring the depletion layer temperature of a GTO are specified. In this case, a measurement current (I.sub.M) is impressed in the gate circuit, and the voltage (U.sub.GR) between the cathode and gate is measured, with an applied measurement current (I.sub.M), after the transient turn-off processes have decayed. This voltage (U.sub.GR) is at this time dependent on the depletion layer temperature of the GTO. It thus becomes possible to measure the depletion layer temperature directly on the element, that is to say without circuitous routes via a heat sink temperature and calculation of the thermal resistance or the like, and during operation, continuously, and in consequence to monitor and control the stress level on the GTO precisely.

Abstract: This actuating drive (1) for a control valve (2) has a control circuit which sets the actuating drive (1) to correspond with a specified required value from an overriding installation control system. It has, in addition, a main piston (6) sliding in a main cylinder (5) with a drive volume (7), on one side of the main piston (6), which can be acted on in a controlled manner by oil under pressure and has a plate valve (17) fitted upstream of the drive volume (7).The intention is to create an actuating drive, for a control valve, whose dynamic behavior can be improved by relatively simple means. This is achieved by the plate valve (17) being provided with a separate reservoir volume, connected to a drain appliance, for the oil emerging from the plate valve (17).

Abstract: A method of establishing part-load operation is proposed for a turbine group. This gas turbine group consists essentially of a compressor unit (1), of an HP combustion chamber (4) downstream of the compressor unit (1), of an HP turbine (5) downstream of this HP combustion chamber (4), of an LP combustion chamber (8) operating by self-ignition and arranged downstream of the HP turbine (5), the hot gases (10) of which LP combustion chamber (8) being admitted to an LP turbine (11). The temperature at outlet from the HP turbine (5) remains essentially the same due to the reduction of the fuel quantity in the LP combustion chamber (8) to zero. Furthermore, the fuel quantity of the HP combustion chamber (4) remains approximately constant during the reduction of the fuel quantity in the LP combustion chamber (8) so that the temperature at inlet to the HP turbine (5) likewise remains constant.

Abstract: In a method of testing weld seams using an eddy-current technique, large-volume and coarse-grained weld seams are subjected to the testing, said weld seams being tested for the presence of faults in layers on-line during their buildup. The method is particularly suitable for testing components with austenitic weld metal. It is notable for a high fault location probability.

Abstract: A method for matching the radial turbines of turbochargers, to the respective internal combustion engine, includes managing with a relatively small expenditure of material and labor time and with low costs. In accordance with the method this is achieved by modifying exclusively gas outlet end components of the radial turbine (1). For this purpose, the vanes (5) of the rotor (6) are first shortened and the flow duct (7) between the hub (8) of the rotor (6) and the gas outlet flange (9) is then correspondingly narrowed. This takes place by the insertion of a different, correspondingly enlarged gas outlet flange (9). For this purpose, the gas outlet flange (9) is fastened to the gas inlet casing (2) so that it is easily releasable.

Abstract: A steam condenser wherein the steam is precipitated on tubes (13), through which cooling water flows and which are gathered into separate bundles. Each bundle is divided into compartments by support plates, the support plates being arranged perpendicularly to the tubes. The tubes, which are arranged in rows and form a bundle, envelop a cavity (19), in which a cooler (3) is disposed for the non-condensible gases. The non-condensible gases flow from the cooler (3) via orifices (6) into a suction channel (4), which is common to all compartments and extends over the entire length of the tubes (13). There is only one cooler (3), to which the suction channel (4) is directly attached, and the passage areas of the orifices (6) in the compartments are dimensioned in such a manner that the local, non-condensible mass flow is withdrawn with the locally available pressure difference.

Abstract: An exhaust gas turbocharger for an internal combustion engine consists essentially of a turbine and a centrifugal compressor, which are both arranged on a common shaft. A vaned diffuser adjoins the compressor impeller driven by the turbine. An auxiliary air drive, which is fed from an external compressed air source, is provided in the compressor part. The auxiliary air drive has a plurality of ejectors by means of which the auxiliary air can be introduced into the region of the diffuser inlet, preferably in the flow direction.

Abstract: In a gas turbine group which consists essentially of a compressor (2), a first combustion chamber (3), a first turbine (4), a second combustion chamber (5) and a second turbine (6), the first combustion chamber (3) is configured as an annular combustion chamber. This annular combustion chamber (3) is operated by a number of premixing burners (11) which are distributed at the periphery. The first turbine (4) is designed in such a way that its exhaust gases have a temperature level which is above the self-ignition temperature of the fuel (13) used in the second combustion chamber (5). This second combustion chamber (5) consists of a burnerless, annular combustion space in which a number of vortex-generating elements (14) are integrated. The turbomachines, namely compressor (2), first turbine (4) and second turbine (6) are disposed on a rotor shaft (1), this rotor shaft (1) being supported in two bearings (9, 15).

Abstract: Horizontal-axis electrical machine having a stator laminate core (1) which is arranged in a housing (2, 3) which is split horizontally, which stator laminate core (1) is clamped by means of fastening wedges (35), which are distributed over its circumference, in supporting rings (32), which are arranged orthogonally to the machine longitudinal axis and are spaced apart from one another. The supporting rings are connected on their external circumference, via fastening parts (39, 40), to the housing lower part (2) of the machine. The supporting rings (32) have azimuthal fastening plates which run symmetrically with respect to the vertical plane of symmetry of the machine.In order to decouple the stator laminate core (1) from the housing lower part (2), the fastening plates (40) are fastened to the said supporting rings such that they are sprung horizontally in the radial direction, the fastening plate (40) itself being constructed as a leaf spring, or acting as such.

Abstract: In a method and an apparatus for influencing the wake of combustion chamber inserts, a passage (5) for guiding an additional air mass flow (3) is arranged in the inserts (2), which passage is connected to outlet openings (6) which are arranged in the part of the inserts located opposite to the main flow (1). The additional air mass flow (3) is, for example, extracted from the combustion chamber cooling air (4), is guided through the passage (5) and is blown out through the outlet openings (6) before the actual combustion zone in such a way that the recirculating flow region is minimized in the wake of the inserts (2).

Abstract: The direct current-electric arc furnace system includes a furnace vessel 8, one or more electric arc electrode 7 connected as a cathode, a bottom contact 12 connected as an anode, a furnace transformer 2 and a rectifier assembly 5 for feeding the furnace, an electrode control system E, and a current regulator I. A choke 6 is switched into the direct current main current circuit. A voltage control circuit F underlies the current control circuit I, whereby the output voltage of the current regulator 14 delivers the desired value for the voltage regulator 24. A filter 25 tuned to the flicker frequency follows the voltage regulator 24 with a frequency response, which is tuned to the frequency sensitivity of the human eye. Optionally, an additional control voltage signal U.sub.flick that is delivered by flicker meter can be provided to the voltage control circuit F.

Abstract: When mounting the winding ends of a stator winding in a dynamo, at least an outer ring of synthetic resin saturated cord ring is wound in multiple windings on the winding ends in its plastically deformable state. The synthetic resin does not harden until after the cord ring is affixed. The outer ring is adapted to be installed in the cramped winding head space and is especially suitable for retrofitting purposes.

Abstract: A premixing burner on the double-cone principle consists essentially of two hollow conical partial bodies (111, 112) which are interleaved in the flow direction and whose respective center lines (113, 114) are offset relative to one another. The adjacent walls of the two partial bodies form tangential gaps (20) in their longitudinal extent for the combustion air. Gas inlet openings (117) distributed in the longitudinal direction are provided in the walls of the two partial bodies. The air is guided into the tangential gaps (20) via vortex generators (9) of which a plurality are arranged adjacent to one another. The fuel is introduced into the gaps (20) in the immediate region of the vortex generators (9).Using the novel static mixer which the three-dimensional vortex generators represent, longitudinal vortices without recirculation region can be generated in the inlet gap through which flow occurs.

Abstract: A mixing apparatus for mixing two or more materials, includes a separating plate Upstream of a mixing zone having a plurality of vortex generators attached to the plate to create large scale longitudinal vortices in the materials as they pass the plate for rapid, controlled mixing in a short longitudinal distance. The vortex generators are arranged in a row transverse to the flow direction of the materials. The vortex generators each comprise three triangular-shaped surfaces joined to form a three sided wedge having a top surface and opposite sides surfaces that project into the flow path. The side surfaces are joined at an acute angle. The top surface is oriented at an angle to the plate. The angles may be adjusted for the type of materials to be mixed.

Abstract: The heat- and creep-resistant steel has a martensitic microstructure produced by a heat-treatment process. The composition of the steel in percent by weight is as follows:0.001-0.05 of carbon0.05-0.5 of silicon0.05-2.0 of manganese0.05-2.0 of nickel8.0-13.0 of chromium0.05-1.0 of molybdenum1.00-4.0 of tungsten0.05-0.5 of vanadium0.01-0.2 of niobium2.0-6.5 of cobalt0.1-0.3 of nitrogen,the remainder being iron and unavoidable impurities. Such a steel can be produced by forging, casting or by powder-metallurgical means. Components fabricated from this steel show a high strength and ductility at room temperature and are distinguished at temperatures of 600.degree. C. and higher by a very high creep strength and an unusually high oxidation resistance. They can therefore be used with advantage as mechanically and thermally highly stressed components in steam- and/or gas-operated power stations.

Abstract: An insulated-gate bipolar transistor (IGBT) is specified, the collector (7) and source regions (8) of which can be produced by means of a self-aligning method. This provides an IGBT which is distinguished by a homogeneous turn-off current distribution. For this purpose, the width W of the source regions (8) is selected to be so small that holes can flow laterally into the surrounding collector region. In this connection it must be ensured that the voltage drop across the PN junction of the source regions and collector regions remains below the inherent forward voltage at any time. In consequence, the IGBT according to the invention is particularly insensitive to latch-up.

Abstract: The iron-aluminum alloy comprises the following constituents in atom percent:______________________________________ 12-18 aluminum 0.1-10 chromium 0.1-2 niobium 0.1-2 silicon 0.1-5 boron 0.01-2 titanium 100-500 ppm carbon 50-200 ppm zirconium remainder iron. ______________________________________This alloy is distinguished by high thermal-shock resistance and, at temperatures of 800.degree. C., still has comparatively good mechanical properties. The alloy can be used advantageously in components such as, for example, casings of gas turbines, which, with comparatively low mechanical loading, are subject to frequent thermal cycling.

Abstract: In a method for operating a combined cycle power plant with coal or oil gasification, wherein the oxygen required for gasification is supplied by an air separation plant, the air required for the air separation plant is condensed in a first, separate condenser and is cooled in a heat exchanger prior to being supplied to the air separation plant. Only enough nitrogen produced in the separation plant is supplied to the gas turbine combustion chamber as the surge limit of the compressor permits. The remaining portion of the nitrogen is expanded to ambient pressure in an expander after exiting the air separation plant.

Abstract: A converter bridge includes at least two half bridges, which are connected together by bus bars. The bus bars include at least two directly opposite bus bar segments and are arranged mirror symmetrically relative to a median plane in the converter bridge. The directly opposite bus bar segments exhibit a relatively small line cross section. Due to the mirror symmetrical arrangement, a high frequency secondary current component, which flows in the opposite direction and belongs to the current flowing through the bus bars, is concentrated in the directly opposite segments of the bus bar and is damped effectively via the relatively small line cross section. In contrast, the low frequency main current component flows in essence uniformly distributed over the profile of the bus bar.