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| Title: | Results Of Extra Fire tests On A Transport Container For UF | ||||
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| Author: | S. Kobayashi | ||||
| Abstract: | The Central Research Institute of Electric Power Industry, under a contract with the Science and Technology Agency of Japan, conducted tests more severe than those required by regulations on the container used to transport UF6 in order to obtain various data on its behavior under severe heat conditions. The fire test conditions were as follows: 1: 800 degree C � 60 min; test II: 1000 degree C � 30 min; test III: 800 degree C � long period test. Before these extra fire tests, preliminary tests were carried out, using a partial scale model to investigate the properties of phenolic foam, which was supposed to burn out under test conditions. Finite element analysis was used for the numerical analysis and to simulate the irreversible properties of phenolic foam and the heat effects of the gas generated from the phenolic foam (which fills the space between the cylinder and guard casing). The main results are (1) In the 800 degree C � 60 min and 1000 degree C � 30 min tests, the increase in temperature on the outer surface of the 30B cylinder was small and no change in leakage characteristics was found. In the 800 degree C- long period test, it took almost 4h for the container to reach 120 degree C on the cylinder surface and during this period no change in seal leakage characteristics was found. (2) In the fire test, it was observed that the heat flux (which flows into the cylinder) was not the only one flowing toward the guard casing; there was also a heat effect caused by gas generated from the phenolic. (3) The fire resistance capacity of the container depends on the carbonizing speed of phenolic foam and this speed of phenolic foam and this speed in turn depends on the particular temperature at the time. (4) The results of the numerical analysis of heat generation effects from phenolic foam agree well with the results of the fire resist stance tests. | ||||
| Report: | FSR-0103 | Pages: | 7 | Size: | 521 KB |
| Title: | Review of Three Recent Developments in Flame-Retardant Treatments for Cotton | ||||
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| Author: | J. David Reid | ||||
| Abstract: | Bromine containing derivates of phosphonitrillic chloride were investigated as possible durable flame retardants for cotton fabrics. These, including brominated allyl phosphontrilate, 2-3 dibromopropyl phosphonitrilate, and the bromoform adduct polymer of allyl phosphonitrilate were applied to cotton fabric as polymertic products from organic solvent or from aqueous emulsions. Evaluation tests on tear strength and the durability of the flame resistance to laundering were made. | ||||
| Report: | FSR-0162 | Pages: | 14 | Size: | 0.99 MB |
| Title: | Silica Reinforcement and Char Reactions in the Apollo Heat Shield | ||||
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| Author: | D.E. Cagliostro, H. Goldstein, J.A. Parker | ||||
| Abstract: | Reactions of the silica reinforcement fiber and ablation char of the Apollo heat shield have been investigated by laboratory tests in an arc image furnace at temperature levels up to 5000 degree R, pressure up to 0.7 atm, and heat flux similar to reentry, 400 Btu/ft sec, and by actual reentry test. Micro chemical analyses and X-ray diffraction studies have been made to determine the presence of SIC formation in the char. Experimental data and analytical predictions of thermal and density profiles have been compared for ablation of virgin heat-shield and precharred materials to determine the effects of SIC formation on ablation performance. In all analyses, general agreement was found between chemical composition and he thermal predictions for laboratory tests and reentry materials. In all ablated materials SiC was formed in the front surface of the char. The highest SiC content found was 58% by weight and found in a high-pressure environment. The SiC formed was found to act as a heat sink in the ablation process and can lower the front surface temperature by 300 degrees R. | ||||
| Report: | FSR-0036 | Pages: | 25 | Size: | 740 KB |
| Title: | Simulated In Flight Fire Test Of A Self-Generating Overheat Detection System | ||||
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| Author: | Richard G. Hill | ||||
| Abstract: | Tests under simulated flight conditions were conducted on a Self-Generating Overheat Detection System installed in a C-140 engine nacelle. They were run with the system in its normal configuration and also with a section of the detection cable pinched, opened and shorted. The system was monitored for fire response time as well as for false alarms. The system performed well in its normal, pinched and opened, configuration, but the alarm time was increased by over 100 percent when the cable was shorted. No false alarms were noted during testing. |
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| Report: | FSR-0033 | Pages: | 22 | Size: | 1.63 MB |
| Title: | Smoke Detectors | ||||
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| Author: | |||||
| Abstract: | The ability to detect a fire in a spacecraft in its earliest stages is difficult to predict. The spacecraft is an extremely complex vehicle in which most of he system and/or equipment likely to act as initiators and propagators of fire are built into hidden areas or installed in semi-sealed cabinets. It is possible that over-heated; incipient fire conditions could exist for a long time before becoming visible. The purpose of this presentation is to discuss one class of devices capable of sensing these conditions and thus providing an early warning. These are so-called �smoke detectors�, which can detect the presence of many of the invisible and visible products of pyrolysis which are given off by most potentially combustible materials when over-heated or in early stages of combustion. In principle smoke detection is one of the simplest and least ambiguous of the available techniques, which might be used for identifying the presence of an active or incipient fire. Normally, combustible materials such as hydrogen for fuel cells and propellants for altitude stabilization and propulsion will be stored exterior to the pressurized living area. Many of the materials likely to be brought on board a spacecraft will be relatively fire resistant. Much of the materials, synthetic polymers of many kinds, do not burn easily, and if involved in pyrolysis through overheating or arcing, break down into complex compounds which should be relatively easy to detect. There will undoubtedly be some relatively flammable materials on board, such as ethylene glycol in heat exchangers or even Kleenex for the crew. Insofar as is known, the products of pyrolysis of all of the materials which are inside the spacecraft can be detected by the smoke detectors. The problem is in space as it is in ground installation, primarily one of proper sampling. This will involve considerable study and research to determine the best location for the sensing units or sampling tubes. Serious consideration should be given to special flight experiments to develop thorough understanding of the factors involved at both zero �g� and partial conditions. Most smoke particles range from 0.01 micron to 1.0 micron in size, which are too small to be seen by the human eye. Tobacco smoke for instance, is composed of particles in the 0.01 to 0.1 micron size, and is visible as a haze only when sufficiently concentrated. In the extreme cases, particles of combustion can range up to 10 microns or larger, but these are generally such substances as fly ash or dusts of various kinds and are not considered here. Several kinds of smoke/ionization detectors are presently commercially available, although none are suitable for application to space flight without repackaging or re-engineering. All of the systems may be intentionally deactivated for certain normal spacecraft functions and all systems can be built to automatically reset to the detection mode when the alarm condition is corrected. The success of any of these systems is critically dependent on the careful matching of requirements with the available hardware. They fall into basically three categories. |
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| Report: | FSR-0031 | Pages: | 23 | Size: | 807 KB |
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