flow

Experimental Evaluation of an Empirical Equation in a Gaseous Flow

In this paper, the estimation error of Dr. Pole's empirical equation was evaluated using copper pipes of different diameters (0.00953, 0.0127, 0.01588 m), under different flow pressure conditions (0, 300, 500, 1000, 1500, 2000, 2500, 3000 L/h). To carry out the experiments, the following instruments were used: an air compressor, 2 flow valves, a needle valve, a gas rotameter, copper piping, pressure gauges and transmitters, a Norus data logger with 4 to 20 mA output signals, thermocouples, and thermoresistors.

СOMPARATIVE CHARACTERISTICS AND SELECTION OF SPEED BEARINGS

The characteristics of bearing supports have been considered. Improving the efficiency of mechanical processing, the quality of operation of mechanisms that use sliding bearing supports, and ensuring stable operation are always important tasks. Solving these tasks contributes to reducing labor costs, reducing operating costs, and increasing the productivity of individual operations.

Investigation of Turbulence Parameters Influence on Results of CFD Modeling of Flow in Ultrasonic Flowmeter

The article investigated the influence of turbulence parameters of the SolidWorks Flow Simulations CFD package on the results of flow simulation in a two-path ultrasonic flowmeter. It has been found that the main turbulence parameters of SolidWorks Flow Simulations (turbulence intensity, turbulence length, turbulence energy and turbulence dissipation) slightly affect the result of the flow simulation in a full-filled pipeline of circular profile without additional turbulous elements (turbine, rotor, other).

Mathematical study of energy characteristics of centrifugal pump with single-vane impeller

In the article, the design of a centrifugal pump with a single-vane impeller is described and a theoretical calculation of such a pump is provided.  The analysis of experimental investigations and the comparison with theoretical calculations are carried out.  For the first time, the operating characteristics of a pump with a single-vane impeller of this type are obtained for different values of the rotation frequency.

Optimization methods for telecommunications networks physical and logical structures

The article deals with reasons why the planned network resource is not used completely. The main attention is paid to the dynamic routing protocol, which does not consider the current load of local network segments according to the principle of its functioning. In the paper local segments loading considers with existence of a constant flow to reduce the computational complexity of the proposed method. The method is proposed in the work to maximize the use of network resources and resource allocation improving based on alternative routes variation through less loaded local segment.

Взаємодія вітрових потоків з огороджувальними конструкціями висотних будівель

This article describes the formula determining the temperature, velocity and force of wind flow around the buildings. The dependence of wind speed and temperature difference, showing the distribution of aerodynamic coefficients on the facade of the building in different directions of wind flow. The basic building envelope and the effect of surface roughness on the flow around buildings.

Analysis of ventilation rate and concentrations of carbon dioxide in the office

The aim of the article is to establish the necessary air exchange rate in the room at the principal production carbon dioxide calculation and experiment. In order to determine the necessary volume the air flow was made more experimental measurements in selected rooms. From the measured data of concentration CO2 by combination of graphic method and mathematical formulas we can determinate the required air flow which meets the hygiene requirements. The entire computation we can see on the example.

Measurement of Roughness of Internal Surface of Measuring Pipeline in Real Time for Standard Orifice Plates

Methods for measuring the roughness of the internal surface of a measuring pipeline for projected rectilinear sections of a measuring pipeline and for rectilinear sections that are in operation have been determined. The new equations for calculating the hydraulic resistance coefficient of friction of natural gas on the internal surface of the measuring pipeline, the average value of natural gas pressure along the section of a measuring pipeline and the equivalent roughness were obtained.