Please help us test our new pre-print finding feature by giving the pre-print link a rating. A 5 star rating indicates the linked pre-print has the exact same content as the published article.
Abstract: A diagram is constructed for the change in titanium alloy VT-6 hardness in relation to relative compressive strain. A relationship is revealed between the hardness of titanium alloy subjected to a different degree of plastic compressive deformation and ultimate strength. It is found by experiment that for titanium alloy VT-6, depending on the degree of deformation during compression, the proportionality coefficient k in the empirical relationship σf = k·HB is 0.48. PubDate: 2023-02-02
Please help us test our new pre-print finding feature by giving the pre-print link a rating. A 5 star rating indicates the linked pre-print has the exact same content as the published article.
Abstract: The article considers the possibility of using a standard method for calculating the transmitted torque of an end magnetic coupling with thin high-coercive permanent magnets 4.5 mm thick from a samarium-cobalt rare-earth alloy (KS-25DC). The air gap between the magnets in the half-couplings of the end coupling varies from 5 to 20 mm. Based on the results of the research, correction coefficients were introduced into the method for calculating the transmitted torque of an end magnetic coupling with thin magnets. It is noted that end magnetic couplings are used with an air gap between the magnets of the half-couplings in the range of 5–12 mm. PubDate: 2023-02-02
Please help us test our new pre-print finding feature by giving the pre-print link a rating. A 5 star rating indicates the linked pre-print has the exact same content as the published article.
Abstract: The design of a separation device with square channels for separating fine particles from gas streams is proposed. The influence of design and technological parameters, such as gas velocity, particle diameter, size of separation zone, and breadth of square channels, on the efficiency of catching solid particles from gas stream was analyzed. Equations for determining the efficiency of particle separation and an exponential equation of the dependence of the separation efficiency of the device on the Stokes numbers are proposed. The calculations showed that a separation device with square channels is efficient for separating fine particles (for particles larger than 5 μm, the separation efficiency of the device is close to 100%). PubDate: 2023-01-27
Please help us test our new pre-print finding feature by giving the pre-print link a rating. A 5 star rating indicates the linked pre-print has the exact same content as the published article.
Abstract: Liquid film flow in channels of regularly structured packing for mass-transfer apparatuses was studied by computer simulation. It was established that steady performance of the packing and the gas speed variation range width depend on the hydrodynamics of the liquid film flow along the channel walls. Data were obtained on the liquid film thickness and the film flow speed with and without air counterflow. The effect of gas speed and liquid viscosity on the liquid film thickness and speed was determined. PubDate: 2023-01-26
Please help us test our new pre-print finding feature by giving the pre-print link a rating. A 5 star rating indicates the linked pre-print has the exact same content as the published article.
Abstract: Research results are provided for tribological properties of non-metallic composite materials taking into account the possibility of their application for compressor vane manufacture. Composite specimens are used for determination of the initial and steady-state friction coefficients, and also average wear intensity. A two-stage experiment is conducted under dry friction conditions and with application of Lukoil-Standart motor oil for friction zone lubrication. As a result of comparing specimen properties material is selected with the best tribological properties and additional recommendations are proposed for a reduction in friction coefficient. PubDate: 2023-01-25
Please help us test our new pre-print finding feature by giving the pre-print link a rating. A 5 star rating indicates the linked pre-print has the exact same content as the published article.
Abstract: The article provides a review of the designs of rolling bearings (given in modern literature, patents and author’s certificates), including designs that improve the load capacity and durability of bearings, reduce their wear and provide bearing lubrication. PubDate: 2023-01-25
Please help us test our new pre-print finding feature by giving the pre-print link a rating. A 5 star rating indicates the linked pre-print has the exact same content as the published article.
Abstract: This study analyzes the influence of crankshaft angular velocity on the working processes, integral characteristics, and coolant movement dynamics of a reciprocating hybrid energy machine with two suction valves. Based on a numerical experiment conducted using a previously developed mathematical model, the coolant consumption in the studied reciprocating hybrid energy machine decreases with an increase in crankshaft rotational speed. In addition, the maximum values of the supply coefficient and indicator efficiency are noted in the range of 700–900 min-1. Furthermore, the amount of relative energy utilized to organize the forced downward flow of the liquid decreases with an increase in crankshaft rotational speed. PubDate: 2023-01-25
Please help us test our new pre-print finding feature by giving the pre-print link a rating. A 5 star rating indicates the linked pre-print has the exact same content as the published article.
Abstract: A classification of devices for winding tubular and flat polymer films is proposed. A critical review of the most characteristic designs of devices is carried out. PubDate: 2023-01-25
Please help us test our new pre-print finding feature by giving the pre-print link a rating. A 5 star rating indicates the linked pre-print has the exact same content as the published article.
Abstract: The design of a distributor for multi-site distribution of various types of bulk and fluid materials in storage tanks and bins of technological equipment is described. Equations are given for determining the key design and technological parameters of the distributor. Possible options of flow lines for transportation and distribution of bulk and fluid materials are discussed. PubDate: 2023-01-25
Please help us test our new pre-print finding feature by giving the pre-print link a rating. A 5 star rating indicates the linked pre-print has the exact same content as the published article.
Abstract: The paper analyzes the effect of injection pressure at constant suction pressure on fluid motion dynamics, operating processes, and integral characteristics of a high-efficiency reciprocating hybrid positive displacement energy machine with two suction valves. As a result of a numerical experiment conducted using a previously developed mathematical model, it was established that the maximum value of the relative coolant flow rate is achieved at an injection pressure of 0.4 MPa and is approximately 120 kg/kg. The gas supply through the leaks of suction valve 2 to intensify the downward movement of the liquid causes the relative gas consumption and relative energy losses, which increase with increasing injection pressure. The maximum value of the indicator adiabatic efficiency is achieved at an injection pressure of 0.5 MPa, while the supply coefficient decreases steadily with increase in injection pressure. PubDate: 2023-01-25
Please help us test our new pre-print finding feature by giving the pre-print link a rating. A 5 star rating indicates the linked pre-print has the exact same content as the published article.
Abstract: The article describes the investigation of the torrefaction process of four samples of biomass (brewer’s grains, sewage sludge, distillery stillage, and coffee grounds) in a fluidized bed in an environment of superheated steam at a temperature of 300°C and in a flue gas environment (oxidative torrefaction) at a temperature of 250°C. It has been established that the torrefaction of brewer’s grains, distillery stillage and coffee grounds produces biochar with a higher carbon content and a higher calorific value than that of the raw biomass. In addition, it has been found that the best raw material for producing biochar among the studied biomass samples is coffee grounds; brewer’s grains is somewhat inferior to it. It is not advisable to use sewage sludge and distillery stillage as raw materials for biochar production. PubDate: 2023-01-25
Please help us test our new pre-print finding feature by giving the pre-print link a rating. A 5 star rating indicates the linked pre-print has the exact same content as the published article.
Abstract: When developing turbomachines for various purposes, designing a blade apparatus (constructing aerodynamically smooth airfoils) is a time-consuming multifactorial task. A promising method for designing airfoils uses the properties of Cremona transformations of a plane with coincident F-points, while the transformation object is the Cassini oval. The results of analytical construction of airfoils lattice by Hirst transformation methods are presented. To implement the proposed mathematical model, an algorithm and a package of applied programs (based on it), which are in fact an automated design system, have been developed. Some calculation formulas are given, the influence of the Cassini oval position relative to the origin of coordinates on the shape of the designed airfoil is described, the main geometric characteristics of the airfoils are calculated, examples of the midline construction and the design of the airfoil leading edge are presented. The proposed mathematical model can be an independent calculation system, a CAD subsystem (software module) or a page of an electronic airfoil catalogue. PubDate: 2023-01-25
Please help us test our new pre-print finding feature by giving the pre-print link a rating. A 5 star rating indicates the linked pre-print has the exact same content as the published article.
Abstract: During diabatic rectification, the internal flows of the mixture being separated change along the column height due to heat exchangers placed on plates through which the heat carrier circulates. The authors of the article propose a scheme for implementing diabatic rectification with integrated coil reflux exchangers in a poppet column and present a mathematical description of the process of heat removal from them during condensation of ascending vapors of ethyl alcohol–water mixture under separation on the coil pipes. The thermal power of the built-in reflux exchanger is determined by considering the influence of thermophysical properties and the location of the coils. An increase in the coolant’s temperature at the outlet of the coil deflector leads to a decrease in thermal power. All other conditions being equal, the largest amount of thermal power falls on the lower plates of the column. The values of the average heat transfer coefficient during condensation of liquid vapors increase with an increase in the coolant’s temperature (water) at the outlet of the reflux exchanger, however, the linear heat transfer coefficient decreases. To increase the thermal capacity of the reflux exchangers (and, consequently, the efficiency of separation of liquid mixtures) it is advisable to use various methods of intensifying heat exchange from the outside of the pipes., PubDate: 2023-01-25
Please help us test our new pre-print finding feature by giving the pre-print link a rating. A 5 star rating indicates the linked pre-print has the exact same content as the published article.
Please help us test our new pre-print finding feature by giving the pre-print link a rating. A 5 star rating indicates the linked pre-print has the exact same content as the published article.
Please help us test our new pre-print finding feature by giving the pre-print link a rating. A 5 star rating indicates the linked pre-print has the exact same content as the published article.
Please help us test our new pre-print finding feature by giving the pre-print link a rating. A 5 star rating indicates the linked pre-print has the exact same content as the published article.
Abstract: An experimental study is made of the wear resistance of a solid lubricant antifriction coating “Modengy 1006” applied to the journal and thrust foils of radial and axial gas dynamic bearings in order to determine coating operating capacity during the life of a micro-GTU. A test procedure for determination of the antifriction coating wear resistance in rotary test unit is described. Features are revealed for the change in electric drive parameters and foil bearing operation during an entire test cycle. PubDate: 2022-11-01
Please help us test our new pre-print finding feature by giving the pre-print link a rating. A 5 star rating indicates the linked pre-print has the exact same content as the published article.
Abstract: The article proposes a design of a roll-type electrochemical membrane apparatus for the effective separation of solutions of chemical and machine-building industries. This design provides an increase in the total area of the membranes and the cooling surface in the apparatus design unit (compared to analogues). The article proposes a method for calculating a roll-type electrochemical membrane apparatus, which allows determining its design parameters (total cooling surface, separation area, and areas of nearcathode, near-anode membranes). PubDate: 2022-11-01
Please help us test our new pre-print finding feature by giving the pre-print link a rating. A 5 star rating indicates the linked pre-print has the exact same content as the published article.
Abstract: A classification of devices for fixing contact plates in the bodies of mass transfer column apparatuses is proposed. The most typical designs of plate supports are considered. PubDate: 2022-11-01
Please help us test our new pre-print finding feature by giving the pre-print link a rating. A 5 star rating indicates the linked pre-print has the exact same content as the published article.
Abstract: An improved higher-efficiency alkylation reactor design has been developed and the principle of operation of such reactor is given. The components of the reactor are described. The flow velocity isocontours in the control sections of the reactors of conventional and modernized designs, based on which the efficiency of use of new technical solutions is confirmed, are obtained. PubDate: 2022-11-01
Hybrid journal (It can contain Open Access articles)
[2467 journals]
