[en] It is shown that it is possible to measure continuously temperatures of plasma-flames up to 5,000 K by using a Xenon-Highpressure-Lamp as a comparison radiator. A method is developed for calibrating a regulable comparison radiator absolutely by knowing only one point of its temperature-curve exactly. (orig.)

[en] Fabrication of quality radiator bars and plates is paramount to a successful DIRC project. This write up discusses the trials and tribulations of the manufacture of ∼600 bars for the BaBar DIRC project and discusses the history and current capabilities of InSync, Inc.

No abstract available

[en] We explore possibilities for THz sources from 0.3-30 THz. While still inaccessible, this broad gap is even wider for advanced acceleration schemes extending from X or, at most, W band RF at the low end up to CO₂ lasers. While the physical implementations of these two approaches are quite different, both are proving difficult to develop so that lower frequency, superconducting RF is currently preferred. Similarly, the validity of modeling techniques varies greatly over this range of frequencies but generally mandates coupling Maxwell's equations to the appropriate device transport physics for which there are many options. Here we study radiation from undulatory-shaped transmission lines using finite-difference, time-domain (FDTD) simulations. Also, we present Monte-Carlo techniques for pulse generation. Examples of THz sources demonstrating coherence are shown with the goal of optimizing on-chip THz radiators for applications that may lead to accelerators

[en] This paper presents a set of parametric studies performed on automotive radiators by means of a detailed rating and design heat exchanger model developed by the authors. This numerical tool has been previously verified and validated using a wide experimental data bank. A first part of the analysis focuses on the influence of working conditions on both fluids (mass flows, inlet temperatures) and the impact of the selected coolant fluid. Following these studies, the influence of some geometrical parameters is analysed (fin pitch, louver angle) as well as the importance of coolant flow lay-out on the radiator global performance. This work provides an overall behaviour report of automobile radiators working at usual range of operating conditions, while significant knowledge-based design conclusions have also been reported. The results show the utility of this numerical model as a rating and design tool for heat exchangers manufacturers, being a reasonable compromise between classic ε - NTU methods and CFD

[en] The device allows economic repair of large straight-tube type heat exchangers by inspecting all tubes one after the other with respect to tightness and tightly sealing defective tubes in one working step. For this purpose nearly equal testing equipment is installed within the inlet and outlet chambers outside the tube plate on both ends of the heat excahnger. The devices are first brought into the correct position with respect to the tube muzzles by means of electric-hydraulic remote-control and then fixed in this position. At first each pipe is approached by a test piston and, through bores contained in it, subjected to a gaseous testing medium. If a tube is found to be tight the next one will be approached. If a tube is not tight at both ends explosion rivets are introduced into this tube; these are ignited by a heated filament and the tube is tightly closed. Outside the intervention zone each of the spaceous instruments is folded up to about half its volume, so that it may be inserted into the two chambers; within the chamber each instrument is folded out into operating position by its own drive mechanism. The device may also be used for contaminated heat exchangers, e.g. for recuperators and coolers in high-temperature reactors. (ORU)

[en] Heat exchange system integrated in the main vessel of a molten salt reactor, comprising a reactor skirt containing the active core, a main vessel around the reactor skirt assembly, pumps and primary exchangers, an external vessel over the main vessel and a thermostatic coolant between the main and external vessels, maintaining the wall of the main vessel at a temperature under that of the melting temperature of a crust of nuclearly inactive salt that forms the solid salt coat protecting the internal surface of the main vessel, characterised in that the extraction of calories out of the core is carried out by means of independent thermal transfer modules, each composed of a primary exchanger and a pump, each module being suspended in the intermediate space between the main vessel and the reactor skirt and resting via a bearing located at its base on a cooperating bearing fitted around an orifice made in the wall of a supporting ring fixed to the skirt of the reactor towards its base and right around it, this ring extending from the skirt to near the main vessel in the solid protective salt crust

[en] Growing international concern about radioactive sources after the Sept. 11, 2001 event has led to a strengthening of physical safety. There is evidence that the illicit use of radioactive sources is a real possibility and may result in harmful radiological consequences for the population and the environment. In Brazil there are about 2000 medical, industrial and research facilities with radioactive sources, of which 400 are Category 1 and 2 classified by the - International Atomic Energy Agency - AIEA, where large irradiators occupy a prominent position due to the very high cobalt-60 activities. The radiological safety is well established in these facilities, due to the intense work of the authorities in the Country. In the paper the main aspects on radiological and physical safety applied in the large radiators are presented, in order to integrate both concepts for the benefit of the safety as a whole. The research showed that the items related to radiation safety are well defined, for example, the tests on the access control devices to the irradiation room. On the other hand, items related to physical security, such as effective control of access to the company, use of safety cameras throughout the company, are not yet fully incorporated. Integration of radiation and physical safety is fundamental for total safety. The elaboration of a Brazilian regulation on the subject is of extreme importance

[en] Full text: Function of electromagnetic coil is to generate magnetic flux for electromechanical devices like linear actuator, motor etc. Electromagnetic coils are used in the Advanced Magnetic Jack Mechanism (AMJM) and In-Vessel Control Rod Drive Mechanism (IV CRDM) to control the motion of the rod in the reactor. This paper describes results of the thermal analysis with several candidate materials to design the electromagnetic coil for desired high temperature (∼ 350 deg C) service life by using well established software to study the thermal design for in-vessel control rod drive mechanism. A test model of electromagnetic coil is fabricated and tested at room temperature (30 deg C). The measured temperatures from the test model at selected locations (along radial and axial direction) have been used to validate the design methodology by finite element analysis. Various candidate materials (Ceramic fiber, glass fiber, mineral insulated conductors) for electromagnetic coil have been analyzed to investigate the suitability for high temperature (∼ 350 deg C) applications. This study will be useful for designing electromagnetic coils for in-vessel control rod drive mechanism

[en] A brief overview of failure indication, repair and maintenance methods of heat exchangers in nuclear power plants is presented. Two major techniques are applied for detecting failure in the heat exchanger: leak testing, erosion and wear inspection. Various water chemistry methods are shown for leakage identification. General repair methods depending on the type of failure are summarized, and some novel techniques are proposed. Thermal calculations are shown to be a useful method for heat exchanger maintenance and failure prevention. (R.P.) 2 figs.; 1 tab