Multivariate Analysis of Variance in Estimating the Operational Reliability of Rotary Microcryogenic Gas Refrigerating M
- PDF / 340,664 Bytes
- 8 Pages / 594 x 792 pts Page_size
- 56 Downloads / 165 Views
CRYOGENIC EQUIPMENT, PRODUCTION AND APPLICATION OF INDUSTRIAL GASES. VACUUM TECHNOLOGY MULTIVARIATE ANALYSIS OF VARIANCE IN ESTIMATING THE OPERATIONAL RELIABILITY OF ROTARY MICROCRYOGENIC GAS REFRIGERATING MACHINES I. A. Arkharov, E. S. Navasardyan, and N. E. Shishova
UDC: 621.59
Features of the application of multivariate analysis of variance (MANOVA) to assess the reliability of microcryogenic gas refrigeration machines (MCGRM) are considered. Using multivariate analysis, it is possible to carry out the calculation, design and optimization of assemblies and parts that make up the MCGRM, while assessing the reliability of components at the design stage. An example of the formation of a block of initial data for MANOVA obtained in the course of test experiments for measuring the temperature at the cold end of the MCGRM displacer by three independent factors (ambient temperature, design and porosity of the regenerator packing) is given. The implementation of multivariate analysis of variance was carried out in the mathematical statistics software (Statgraphics technologies Inc.). The use of MANOVA allows the acquisition of accurate data on the influence on the reliability of the MCGRM of various factors (environmental parameters, design, technical characteristics) in order to determine the depth and priority of improving the devices and components of the MCGRM. Keywords: MCGRM, reliability, mean time between failures (MTTF), multivariate analysis of variance (MANOVA).
The development of special photometric systems in applications such as satellite navigation and communication systems, thermal imaging devices, surveillance systems, and missile attack warning systems [1] is associated with the use of cooled photodetectors having a linear or matrix arrangement of sensitive elements providing an increase in resolution and a reduction in photodetector response time [2]. Photoreceivers operating in the infrared range of the spectrum (wavelengths of 3–5 and 7–14 μm) are used in cameras and forward-looking infrared (FLIR) aviation and satellite systems. During the operation of such devices, it is necessary to cool the matrix of a photoelectronic cell to cryogenic temperatures using microcryogenic gas refrigerating machines (MCGRM). Under the conditions of extra-terrestrial space, increased requirements are imposed on cooling systems in terms of reliability and durability of operation, as well as maintenance of the specified parameters for the cryostatting temperature and power consumption of the MCGRM. Expensive tests and a constant increase in the duration of the failure-free operation of the MCGRM necessitate the search for new methods of predicting the reliability of these systems, including the early stages of their development and design. MCGRM manufacturers have developed their own methods for predicting reliability. At the enterprises of Thales LAS (France) and Ricor (Israel), a method for predicting reliability is used based both on statistical data on failures during predominantly accelerated tests of the MCGRM an
Data Loading...
