RESEARCH OF SOURCES OF VIBRATION IN ELEMENTS OF PIPELINES OF HEAT EXCHANGERS AND CONSTRUCTIONS TRANSPORTING HIGH-VISCOSITY LIQUIDS

Abstract

With the signing of the Association Agreement with the EU, Ukraine took a number of obligations to reduce primary energy costs, incl. and in heating, ventilation, air conditioning systems and reduce the energy consumption of production. Along with this, the problem of thermal pollution of the environment, caused by an increase in emissions of greenhouse gases and pollutants into the atmospheric air with exhaust air, also requires a solution. All this requires the design of reliable and efficient energy storage systems, which will not only provide a stable energy supply to consumers, but also increase the energy utilization rate, as well as modernization of production processes and effective methods of cleaning exhaust air before it is released into the atmosphere. A method for studying vibration sources in pipeline elements of heat exchangers and structures transporting high-viscosity liquids, for example, in heat exchangers for charging and discharging heat accumulators, pipelines for transporting concrete solution and pipelines and structural elements for removing a mixture of dirt that is formed in scrubbers when cleaning dirty air with using water droplets from dust. To combat pipeline vibrations, proper design of pipeline systems is of great importance, which makes it possible to influence the hydrodynamic forces in pipelines and structural elements, which are the sources of these vibrations. It is shown that the hydrodynamic forces in pipelines are distributed over their entire inner surface, and in determining them it is useful to follow the path of a number of simplifications. It is useful to go from forces distributed over the surface to forces distributed along the axis of the pipeline by averaging the forces acting along the perimeter of each section. Since the forces along the axis of the pipeline are very unevenly distributed, it has been experimentally shown that the most intense are the hydrodynamic forces in the sections with abrupt changes in the geometry of the channel (the so-called local resistances), therefore, slightly curved sections of a constant cross-section should prevail, since the hydrodynamic forces in them are much less. The coefficients of similarity of the hydrodynamic force have been established, which depend only on the properties of the medium flowing through such channels. The same coefficients of similarity were found for the moments of forces. The spectra of force and characteristic frequencies are determined, where the intensity of the force is high.