[en] This paper describes the thermal-hydraulic characteristics and basic design of the recirculating steam generation

[en] A prototype of the consolidated steam generator has been operating in the advanced pressurized water reactor (APWR) on the NS OTTO HAHN since 1968, and it is planned to install one in a nuclear container ship (NCS-80). The design, technology and operation of the consolidated steam generator are radically different from those of the vertically shaped U-tube steam generator installed in commercial pressurized water reactor plants of the loop type. The features which differ are compared with particular reference to corrosion. Aspects of the operation of the APWR-steam generator on NS OTTO HAHN are described

[en] The CO₂ neutral generation of energy and increasing fuel costs are the two central future challenges for energy-intensive industries. In addition to generating electricity and heat from renewable energies, industrial and commercial users have already obtained good results for several years with process steam from biomass up to 10 MW. The technology is mature, is subsidised with government incentives, and has a payback of two to three years. (orig.)

[en] Data resulting from the operation of the Solar Central Receiver Steam Production System at Weizmann Institute of Science was compared to data calculated from modelling computer codes on receiver tube surface temperatures, absorbed power, efficiency and steam quality. Good correspondence was shown between calculated and observed data. Extrapolation to higher flux inputs and lower circulation rates using the models indicated that the heat flux on the evaporation panel could safely be raise to 900 kw/m² and to saturate steam temperatures of 260 degrees C from the original designed 300 kw/m² and 200 degrees C respectively. Furthermore a preliminary economic analysis indicated that this cavity receiver system could be operated competitively at levels 10-100 megawatts thermal equivalent steam production. (authors)

[en] Paper studies the problems linked with measurement of the water level in NPP steam generators using low base hydrostatic level gages. The standard level gages of steam generators (SG) are shown to be designed for non-boiling liquid conditions. It results in the essential error of water level measurements as to working loads. A scale for low base level gage for various steam loads of SG is designed and offered

[en] Repowering involves replacement of the reactor by a fossil fuel source of steam. This source can be a conventional fossil fueled boiler or the heat recovery steam generator (HRSG) on a gas turbine exhaust. The existing steam turbine plant is used to the extent possible. Alternative fuels for repowering a nuclear plant are coal, natural gas and oil. In today's world oil is not usually an alternative. Selection of coal or natural gas is largely a matter of availability of the fuel near the location of the plant. Both the fossil boiler and the HRSG produce steam at higher pressures and temperatures than the throttle conditions for a saturated steam nuclear turbine. It is necessary to match the steam conditions from the new source to the existing turbine as closely as possible. Technical approaches to achieve a match range from using a topping turbine at the front end of the cycle to attemperation of the throttle steam with feedwater. The electrical output from the repowered plant is usually greater than that of the original nuclear fueled design. This requires consideration of the ability to use the excess electricity. Interfacing of the new facility with the existing turbine plant requires consideration of facility layout and design. Site factors must also be considered, especially for a coal fired boiler, since rail and coal handling facilities must be added to a site for which these were not considered. Additional site factors that require consideration are ash handling and disposal

[en] A rigid supporting device is described. It is intended for permanently connected equipment such as a nuclear reactor vessel and its steam generators. It consists of a double thick metal plate structure, the two parts of which are rigidly fixed together: 1/ The lower part is provided with a central body enveloping and supporting the vessel by means of pivots welded to it. These pivots are adjusted and slide in bearings integrated into the above mentioned structure, which is double skinned by an external body enveloping at least partially the water boxes of the steam generators and supporting the steam generators by adjusted pivots sliding in bearings integrated into this external body. The bottom parts of the central and external bodies are welded onto a thick metallic base. 2/ The upper part is partitioned by vertical extensions of the central body in such a way as to form a discharging reservoir in its central part. Lateral bodies on both sides envelope the steam generator tube bundles. The upper part of these lateral bodies are connected together by casings which act as stiffeners

[en] Small modular reactor (SMR) is very suitable to be deployed in Indonesia especially for locations having low electrical grid capacity, so further investigation on the characteristic of this reactor is needed. In general SMR has a compact and integrated-to-vessel steam generator design. This design implies different approach in producing steam as compared to conventional nuclear power plant having inverted u-tube steam generator. For that reason, this research is intended to investigate the steam characteristic and how it is generated in the helical SG which is widely used in SMR. The method used is through numerical calculation of the SG model using RELAP5 code. In the model, the feed-water which has low pressure and temperature is flown into helical tubes while high pressure and temperature fluid, which represents reactor primary system coolant, stays in outer side of the tube. Calculation result shows that the steam produced by helical steam generator is superheated, i.e. about 25 K above saturation temperature. This provides comparative advantage to SMR on the design and operational aspects compared to conventional reactors because the superheated steam it produces can reduce turbine losses and at the same time increase thermodynamic efficiency. (author)

[en] This work presents the strain measurement procedures applied to a compact nuclear reactor steam generator, during a hydrostatic test, using strain gage technology. The test was divided in two steps: primary side test and secondary side test. In the primary side test twelve points for strain measurement using rectangular rosettes, three points (two external and one internal) for temperature measurement using special strain gages and one point for pressure measurement using a pressure transducer were monitored. In the secondary side test 18 points for strain measurement using rectangular rosettes, four points (two external and two internal) for temperature measurement using special strain gages and one point for pressure measurement using a pressure transducer were monitored. The measurement points on both internal and external pressurizer walls were established from pre-calculated stress distribution by means of numerical approach (finite elements modeling). Strain values using a quarter Wheatstone bridge circuit were obtained. Stress values, from experimental strain were determined, and to numerical calculation results were compared. (author)

[en] A programme at Westinghouse aimed at improving the efficiency and reliability of steam generators has led to the development of the model F generator. Its design features are described and the performance in model boiler and field tests, and in operating plants is summarised. (U.K.)