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The introduction of advanced effective technologies for crushing, separating, mixing, and compacting in the ceramic and other industries is of great practical importance. The Vth international conference devoted to these problems was held, like the previous ones, in the Belgorod-Dnestrovsky District of the Odessa Region in 1997. The results obtained in the discussed field by various scientific schools of the CIS countries were presented. The conference was attended by representatives of scientific schools and mining and processing enterprises in Odessa, Dnepropetrovsk, Kharkov, Kiev, Donetsk, Krivoy Rog, Minsk, Kishinev, St. Petersburg, Ekaterinburg. The organizers of the conference were the Odessa State Marine Academy (department of higher mathematics), the Kharkov State Polytechnical Institute (department of technology of ceramics, refractories, glass and enamels), and the National Mining Academy of Ukraine (department of mining machines) engaged in the scientific programs of the Ministry of Defense of Ukraine, including problems of low-temperature synthesis of refractory compounds.A review by I. I. Blekhman (St. Petersburg) was devoted to methods of testing mechanical systems subjected to vibration, the changes in their mechanical and rheological properties, and the use of effects established in practice in order to . improve compaction of ceramic mixtures on various binders. G. A. Saipeev (Ekaterinburg) described his new method for disintegrating solid particles, i.e., resonance disintegration with the use of hydroquantum resonators, which provides for a very efficient crushing process. The results on crushing various materials in apparatuses based on the described principles show the efficiency of the method and its prospects for the science ofceramic materials.The report ofL. Zh. Gorobets, A. I. Lyuty, and S. B. Dubrova (Dnepropetrovsk, Donetsk) was devoted to the relations between the parameters of dispersed solid bodies and the thermodynamic characteristics of the critical state of a substance. The scientists continue to develop the method considered at the previous two conferences and study the threshold state of the substance that corresponds to the beginning of dispersion from the standpoint of thermodynamics with involvement of the fundamental individual characteristics of the substance parameters, i.e., the pressure, temperature, spe-1 Odessa State Marine Academy, Odessa, Ukraine;Kharkiv Stale Polytechnical University, Kharkov, Ukraine. 60 cific volume, melting and evaporation temperatures, and energies of phase transformations. They demonstrated the possibility of predicting the energy capacity of dispersion of various kinds of ceramic and chemical raw materials from the specified parameters. The use of mechanochemical processes for synthesizing specified phases substantially widens the possibilities of creating new materials; this explains the growing interest in these methods in the science ofceramic materials. The report of G. D. Semchenko, E. E. Starolat, I. N. Opryshko, and L. A. Andropova (K...

Superimposed flow pulsations promote heat transfer intensification. Usage of such flows allows to increase the thermal characteristics aimed at the energy saving. However, the question of the thermohydraulic efficiency of this method remains open, since there are little data of changing in hydraulic resistance in the case of non-isothermal pulsating flow in the channels. To solve this problem, CAD/CFD software SolidWorks/ FlowSimulation was used. Smooth and profiled channels were investigated. A model of periodically pulsating fluid flow in channels with sinusoidal velocity pulses was considered. Pulsating frequency range was set from 0 to 30 Hz. The results showed that a periodic change in the Reynolds number leads to a change in the value of hydraulic resistance over time. At a flow pulsation frequency of 0.5 ≤ f ≤ 5 Hz and 2.8 ≤ lgRe ≤ 3.5 for a smooth channel there are characteristic zones of a laminar (Re≈2000) and transient flow regime (Re = 2000-4000), and a turbulent zone at 3.5 ≤ lgRe ≤ 4.7. With increasing of the flow pulsations frequency f > 5 Hz, there are no zones of laminar and transient regimes, and the flow can be characterized as a stabilized turbulent flow. In contrast to the pulsating flow in a smooth channel, in a profiled channel a stabilized turbulent flow appears already at a pulsation frequency f = 2 Hz (Sh = 0.09). The relative coefficient of hydraulic resistance for non-isothermal fluid movement in a profiled channel is 10-15% higher than in a smooth one. Increasing in the thermohydraulic efficiency, both in smooth and profiled channels, can reach up to 20 -40%.

Experimental studies of a heat exchanger with an improved plate's heat transfer surface are carried out. In the article, various types of solders were investigated and on the basis of the obtained results the technological process of soldering was developed. Testing for the leakage and destruction limit of the heat exchanger was done. The results showed that in comparison with the traditional copper solder in aggressive environments the developed solder composition is close to the chemical composition of stainless steel grades 304/316 and has the same stainless properties as the base material, which provides higher resistance. Tests for the leakage and final strength showed that the additional reinforcing elements added in the design of the heat exchanger improve the reliability of the solder joint, as well as the overall strength of the structure in comparison with the analogue.

Total energy consumption of buildings and structures in the construction sector today accounts for 41 % of the total European Union (EU) energy consumption. For heating and air conditioning are used 85 % of total energy consumption. Therefore, one of the main ways to increasing of the heat power devices efficiency in the future -improvement of the heat exchanging equipment, which can be realized through the introduction of effective heat transferring intensifications methods. Special attention now is paid to studies of pulsating flow influence on heat transferring. Such unsteady flows can be created artificially, or may appear during the operation of the thermal energy equipment, and can be accompanied by increasing and decreasing of the heat transferring intensity. However, the influence of such a regime on a human comfort level is not enough studied. The purpose of this work is to investigate the effect of the pulsating mass flow rate of the circulating media on the thermal power of a panel heating radiator and to analyze the effect of thermal pulsations on the human comfort level. At the first stage, a type P11 steel panel radiator, with overall dimensions of 600x800 mm and operating pressure up to 10 Bar, was studied. The circulating media in the radiator is water. The average mass flow rate of the circulating media is M = 0.1 kg•s -1 , the temperature head is 70 ºC, the pulsation frequency range of the circulating media is from 0 to 5 HZ. At the second stage, the radiator was installed in a model of the room in which people were located, where the influence of thermal pulsations on the level of human comfort was studied. Numerical modeling was carried out with using of the CAD/CFD complex of Solid Works/Flow Simulation software. The complete system of Navier-Stokes equations and the energy equation were solved using the k-ε turbulence model in a non-stationary formulation of the problem. Results of the numerical calculations showed that the periodic pulsating mass flow rate of the circulating media in the heating radiator, compared with the stationary mode, leads to an increase in the average heat flux of the radiator during operation by approximately 25 %. And, as a result, it leads to uncomfortable conditions in the room where people are located.