A method of calculating the conditions of multidepartment compressor stations of gas transmission pipelines

Translated from Russian (Izv. Vyssh. Uchebn. Zaved., Neft' Gaz 1986 (1) p. 65-69)SIGLEAvailable from British Library Document Supply Centre- DSC:9022.048(BG-Trans--8696)T / BLDSC - British Library Document Supply CentreGBUnited Kingdo

Performance of fast reactor mixed-oxide fuels pins during extended overpower transients

The Operational Reliability Testing (ORT) program, a collaborative effort between the US Department of Energy and the Power Reactor and Nuclear Fuel Development Corp. (PNC) of Japan, was initiated in 1982 to investigate the behavior of mixed-oxide fuel pin under various slow-ramp transient and duty-cycle conditions. In the first phase of the program, a series of four extended overpower transient tests, with severity sufficient to challenge the pin cladding integrity, was conducted. The objectives of the designated TOPI-1A through -1D tests were to establish the cladding breaching threshold and mechanisms, and investigate the thermal and mechanical effects of the transient on pin behavior. The tests were conducted in EBR-2, a normally steady-state reactor. The modes of transient operation in EBR-2 were described in a previous paper. Two ramp rates, 0.1%/s and 10%/s, were selected to provide a comparison of ramp-rate effects on fuel behavior. The test pins chosen for the series covered a range of design and pre-test irradiation parameters. In the first test (1A), all pins maintained their cladding integrity during the 0.1%/s ramp to 60% peak overpower. Fuel pins with aggressive designs, i.e., high fuel- smear density and/or thin cladding, were, therefore, included in the follow-up 1B and 1C tests to enhance the likelihood of achieving cladding breaching. In the meantime, a higher pin overpower capability, to greater than 100%, was established by increasing the reactor power limit from 62.5 to 75 MWt. In this paper, the significant results of the 1B and 1C tests are presented. 4 refs., 5 figs., 1 tab

Mechanisms governing fine particulate emissions from coal flames

Efforts in this period focused on refining the plans for engineering analysis and fundamental experiments based on the results of a literature review, and modifying the Malvern laser diffraction particle sizer to operate at particle sizes down to 0.5 microns. The engineering analysis plan is to concentrate on development of new models and adaptation of existing models for fine particulate formation by three categories of mechanisms: particle breakup/ash coalescence; direct passage, fragmentation, or agglomeration of extraneous mineral matter; and bubble formation/breakup. The plan for fundamental experiments is to develop a fast, online, optical particle sizing technique which will span the 0.5 to 10 micron size range of interest; to perform global experiments to identify the important parameters affecting fine particle formation; and to perform mechanistic experiments to test specific hypotheses about the mechanisms which control fine particle formation in coal combustion

Reliability of fast reactor mixed-oxide fuel during operational transients

Results are presented from the cooperative DOE and PNC Phase 1 and 2 operational transient testing programs conducted in the EBR-2 reactor. The program includes second (D9 and PNC 316 cladding) and third (FSM, AST and ODS cladding) generation mixed-oxide fuel pins. The irradiation tests include duty cycle operation and extended overpower tests. the results demonstrate the capability of second generation fuel pins to survive a wide range of duty cycle and extended overpower events. 15 refs., 9 figs., 4 tabs

Evaluation of environmentally safe cleaning agents for diamond turned optics

Precision machining of metal surfaces using diamond turning has increased greatly in popularity at LANL in recent years. Similar techniques are used extensively to manufacture metal mirrors for use in laser applications. The diamond turned surfaces are easily damaged, making the selection of a cleaning agent very critical. These surfaces have been traditionally cleaned using Trichloroethane (TCA) to remove residual oil remaining from the machining process. The TCA was then removed with an ethanol rinse, leaving a residue free surface. Recently, however, TCA was pronounced environmentally unsafe. Consequently, we are searching for an environmentally safe cleaning agent for these diamond turned metal optics. The concern with using alternative solvents is the potential for residual surface films that produce reflectivity changes related to a combination of wavelength, surface coverage, film thickness and dielectric properties. Therefore, we have initiated a program for testing the effectiveness of a variety of environmentally safe solvents used to clean diamond turned optical surfaces. Our basic test plan consists of comparing a number of environmentally safe solvents against the TCA/ethanol cleaning system. We have identified twelve candidate solvents, but have only been able to perform a partial test on one of them to date. This paper discusses the results obtained to data using this solvent known as P F (1). 3 refs., 13 figs