Influence Of Regime Parameters Research Articles

Особенности моделирования шероховатости поверхности при фрезеровании нержавеющих сталей c применением различных сред

Modeling characteristics for surface finish when milling stainless steels using various media (grade steel 12X18H10T) using IOL-20A (industrial oil lubricant), CM-99 (cooling mixture), rapeseed and castor oils and on dry treatment, using the algorithms of the group method of data handling are viewed. The use of various lubricating and cooling technological mixtures (LCTM) is thought of as the theory of metal cutting factor reducing surface undulation. However, the degree of influence of various LCTM, including vegetable oils, when milling steel 12X18H10T has not been determined. The study case of various effects interaction on the milling process has shown that these studies were conducted on the basis of single-phase experiments that do not allow specifying mutual influence of the studied factors on the value of the parameters of the cutting process for various types of treatment. The research methodology provides for modeling surface finish under milling of 12X18H10T steel according to experimental data using various process liquids in the accepted range of cutting modes. At the same time, modern modeling methods allow us to determine these mutual effects. To obtain models, it is urgent, first of all, to be aware of break-in process criterion and dulling tool criterion as well. As a result of processing experimental data for each of processing media, surface finish models in the form of dependencies Ra = f (v, sz, t) were constructed, adequately describing the milling process with various media. It is indicated that the influence of regime parameters on the formation of micro-dimensions take the form of their close interrelation. Their interplay has various effects, depending on the LCTM used for the specified work stock and tool material.

Numerical modeling of two‐phase flows in the presence of dynamic and thermal interactions

AbstractThe study of turbulent flow in mixtures consisting of gas and particulate matter is a current area of research among modern scientists. The main objective of this area is to prevent the reduction of burnout in flow‐through systems. Therefore, the purpose of this research is to develop a mathematical model of turbulent gas flow with solids to explore the structure of the combustion region in a channel with a partially open boundary to determine the interfacial interaction of the injection of a flat heterogeneous flow in a confined area and the influence of regime parameters on the ignition process. For this purpose, a modeling method was used, which involved using the fundamental laws of continuity of flow, conservation of energy, and the quantity of motion and matter, and an experiment was conducted to reconcile the proposed model with theoretical data. As a result of this work, a model based on the averaged Reynolds Navier–Stokes equations and an algorithm for solving a turbulent subsonic two‐dimensional flow in a heterogeneous medium based on an Euler–Lagrange representation have been developed. Thus, the effects of the parameters of entrainment, temperature, and component concentration on the combustion range and mixing intensity were determined. The proposed methodology can be applied to solve application problems of various kinds, for example, in the design of thermal power plants. The scope of the mathematical and numerical models developed is sufficiently broad that they are universal.

СОСТОЯНИЕ И ПЕРСПЕКТИВЫ УЛЬТРАЗВУКОВОГО ЭКСТРАКЦИОННОГО ИЗВЛЕЧЕНИЯ БИОЛОГИЧЕСКИ АКТИВНЫХ ВЕЩЕСТВ

The features of ultrasonic action on biotechnological raw materials of plant and animal origin during the extraction of useful components are considered. The mechanism of the energy impact on the raw material, the sound field solvent, as well as the influence of regime parameters on the main characteristics of the process, is described. The positive dynamics of the complex wave and diffusion effects on the nature and yield of biological substances from plant materials is shown. The performed studies on the extraction of rennet from crushed calf abomasum’s showed an increase in the temperature of the sonicated medium by 13°C and a change in pH due to the formation of H+ and OH– radicals due to cavitation. It has been estab-lished that during the first 4 minutes of sonicating a mixture of crushed calf abomasum’s and a solvent, the pH value of the solution decreases slightly, and subsequently changes to the opposite after the 5th mi-nute. This is followed by a second decline after 20 minutes and scoring. This phenomenon was explained by the formation of a significant amount of HCl free radicals within a microsecond sonication interval, af-ter which a change in the reaction to the reverse was noted. The prospects for research in this area from the point of view of further improvement and development are shown.

Numerical study of the dynamics of synthesis gas adsorption separation

A numerical study of the dynamics of pressure swing adsorption process for synthesis gas separation and hydrogen concentration was carried out. The influence of regime parameters (compressor and vacuum pump outlet pressures, duration of the "adsorption-desorption" cycle, backflow coefficient) and design parameters (height of the adsorbent bulk layer and the internal bed diameter) on the recovery and purity of hydrogen, plant performance in a given range of changes in the temperature, composition and pressure of the initial gas mixture was studied. It is found that when the hydrogen content decreases from 68 to 48 vol. % and a simultaneous increase in the carbon dioxide content in the initial gas mixture from 27 to 47 vol. % required hydrogen purity value at 99.99 vol. % can be achieved by reducing the pressure at the outlet of the vacuum pump from 0.75?105 to 0.5?105 Pa. At the same time, the duration of the adsorption stage increases from 120 to 150 seconds, and the degree of hydrogen extraction decreases from 55 to 52% due to an increase in the proportion of the flow selected for the regeneration of the adsorbent. Increasing the temperature of the initial gas mixture from 293 to 323 K leads to the need to reduce the duration of the adsorption stage from 148 to 42 s due to a decrease in the equilibrium concentrations of carbon dioxide and monoxide in the adsorbent.

Creating molecular weight distribution of butadiene rubber on neodymium-based catalytic system

The method of calculation of the molecular weight distribution (MWD) of rubber SDRN synthesized in the cascade of reactors with a continuous mixer in the presence of chain transfer to the polymer (by direct numerical solution system of equations arising from the kinetic scheme of polymerization with special selection of boundary conditions, maximum length of macromolecules and calculation step value). Numerical solution of mathematical model that is systems of differential equations for concentrations of monomer, co-catalyst and macromolecules of polymer together with thermal balance is obtained. The influence of regime parameters on MWD and molecular mass characteristics of the final product obtained using molecular weight distribution are analyzed.

The influence of regime parameters on kinetics of continuous vibration extraction of plant raw materials

The influence of regime parameters on kinetics of continuous vibration extraction of plant raw materials

Genetic algorithm optimized double-reservoir echo state network for multi-regime time series prediction

In prognostics and health management (PHM), the sensor measurement time series of equipment is collected, and predicting future sensor measurements accurately is crucial to PHM. Complex equipment is generally operated under dynamic operational conditions; thus, operational regime-switching process exists in the sensor measurement time series, which is called multi-regime time series. Different operational regimes may have various effects on time series; thus, the regime-switching process poses great challenge for multi-regime time series prediction. To predict the multi-regime time series accurately, the double-reservoir echo state network (DRESN) is adopted by modifying the conventional echo state network. The DRESN model has two input sequences: the sensor measurement sequence and regime parameter sequence, where the regime parameter reflects the operational regimes and influences sensor measurement; then, two reservoirs try to model these two sequences, respectively; last, the outputs of two reservoirs are aggregated to predict the future sensor measurement. The DRESN model not only considers previous sensor measurements but also takes the influence of regime parameters into account when predicting future sensor measurement; thus, it can improve the accuracy of multi-regime time series prediction. In addition, the training algorithm of the DRESN model is presented and only a linear regression problem needs to be solved, making the DRESN model efficient. To achieve good performance, four parameters of the DRESN model are optimized using genetic algorithm (GA) because GA is effective in solving mixed-integer problem, and the weighted cross validation is adopted in the objective function to achieve the accuracy and simplicity simultaneously. The DRESN model is applied to turbofan engine multi-regime time series and compared with other models. The results validate that the DRESN model can be accurate and stable in multi-regime time series prediction.

Heat transfer experimental research at evaporation of alternative refrigerants R407C and R410A at conditions of free convection

Aim of the work was the influence of regime parameters on heat transfer at evaporation of refrigerants R407C and R410 research. To achieve this aim the experimental stand was designed and made. The article contains results of visual observations for the evaporation process of different refrigerants on horizontal tube in big volume, the connection between heat transfer coefficient and regime parameters, heat flux density and evaporation pressure, was determined.