Експериментальне визначення зміни капілярної утримної здатності сітчастих розділювачів фаз

Abstract

The subject of this study is the process of loss of capillary holding capacity (CHC) as a result of a violation of the balance of external and internal forces on the phase interface (PI) "liquid - gas" of the capillary in the cell of the mesh phase separator (MPS) of the capillary means for ensuring the integrity of the fuel (CMEIF) with a long service life in chemically aggressive fuel components (FP): nitrogen tetroxide (NT) and asymmetric dimethylhydrazine (NDMH). The goal is to improve the selection of design parameters of the CMEIF through the refinement of traditional approaches to the calculation of the CHC MPS depending on the term of their operation. Task: to determine the rate of corrosion of the main structural material of the MPS - steel nets of the twill weave type, and its effect on the structural and geometric characteristics of the nets; to perform an experimental determination of the change in the MPS CHC; to improve the mathematical model for determining the MPS CHC, considering the term of their operation as part of the fuel system of space flight vehicles (SFV). The methods used are as follows: to determine the rate of corrosion - metallographic studies and measurement of the geometric dimensions of mesh samples; to determine the change in CHC - the bubble method. The following results were obtained. The coefficient of the maximum corrosion rate was determined. A new, refined dependence of the average value of Bo cr on the temperature of the FP was obtained. Linear regressions of changes in the approximated values of CHC MPS depending on the duration of their operation were obtained. An increase in the average arithmetic value of the wetting contact angle θ in the NDMG over 31 years of MPS operation was determined. An improved mathematical model for determining the CHC of MPS was obtained, considering the period of their operation in JSC and NDMH. Conclusions. The scientific novelty of the obtained results is as follows: for the first time, comprehensive studies were carried out to determine the rate of corrosion of the main structural material of MPS after a long period of their stay (from 14 to 31 years) in FP (NT and NDMG) and under their pairs, the results of which revealed regularities of flow corrosion processes in the liquid and gas phase, established corrosion rates and deduced coefficients, the application of which improves the engineering methods of calculating the main parameters of MPS; the physical model for calculating Bo kr received further development; the physical model for calculating the CHC has been improved, which makes it possible to calculate the value of the static CHC of the MPS with greater accuracy than it was before and to make the final design of the designed CMEIF more perfect and reliable.