We study heat exchangers at the experimental setup aiming at the energy-saving. The feature of this heat exchange process is of the fact that the working medium is a porous metal. The pores are filled with freon and operation of the refrigeration unit condenser is studied. The scheme of the experimental setup and experiment methodology are given. The results of the experiment and its processing are also presented.

The creation of efficient and compact heat exchangers is one of the priority tasks arising during the design of heat and gas supply to industrial and residential buildings. As a rule, finned surfaces and turbulization of heat carrier flows are used to increase the efficiency of heat exchange in heat exchangers. The present paper proposes to use novel materials, namely porous material, in the design of highly efficient heat exchangers. The investigation was carried out experimentally and theoretically. To study the possibility of creating such heat exchangers, a multi-purpose test bench is created. The aim of the study was to assess the intensity of heat transfer in heat exchangers using porous metal. Laboratory tests are carried out as part of the experimental study. In the theoretical study, the classical equation for the change in the heat flux density when the coolant passes through the porous insert was used. As a result, a mathematical model was obtained in the form of a second-order differential equation. Boundary conditions were set and a particular solution was obtained. The results of theoretical calculations were compared with experimental data. The performed study experimentally confirmed the efficiency of using porous metal inserts in the design of shell-and-tube heat exchangers. The compiled mathematical model allows one to perform engineering calculations of the considered heat exchangers with porous inserts.

Currently, porous metals are not used in heat supply systems. Usage of porous materials in heat exchangers increases the heat transfer intensity and makes the heat exchangers more compact. An experimental setup consisting of two circuits was developed in order to study the influence of porous metals on heat transfer intensity. In the first circuit the hot coolant is water, which flows through narrow tubes inside the porous metal. In the second circuit the cold coolant is freon. The purpose of the study is to obtain experimental confirmation of the hypothesis of an increase in the heat transfer intensity when using porous metals. To achieve this goal, experiments were carried out, which showed the increased heat transfer intensity. The standard methods for calculating heat exchangers cannot be applied in this case as the inner pores’ surface is unknown. A mathematical model was compiled allowing engineering calculations for the heat exchangers of this type. The hot water temperature inside the heat exchanger is determined analytically. The resulting equation allows us to determine the cooling degree of the first coolant, i.e. hot water. The obtained deviations between experimental and analytical data are within the acceptable limits, which indicates the reliability of the proposed model.

This paper proposes using porous metals to boost heat exchanger efficiency. One coolant (Freon) flows through the porous metal, while the other coolant (water) flows through the narrow tubes laid inside the porous metal. The paper presents a mathematical model for a porous-metal heat exchanger, which can find metal temperature changes in any section of the heat exchanger to compare the heat transfer rate of metals of different porosity. Calculation by standard methods is not an option, as the inner surface of pores is unknown. The temperature of hot water inside the heat exchanger is to be found analytically. The obtained equations help determine the degree of cooling the first coolant (hot water). Porous heat exchangers can be used in heating systems.

Heat exchangers are widely used in heat supply systems. To increase the efficiency of heat supply systems, heat exchangers with porous metals are proposed to design. There was a test facility set up to study new types of heat exchangers. The countercurrent flow of heat carriers was activated in those heat exchangers. Freon moved through the heat exchanger pores, and water moved through the inner tubes. It should be noted that the porous materials in the heat exchangers differed in the coefficient of porosity. To be compared, one of the heat exchangers did not contain any porous material. The first test cycle proved the feasibility of using porous metals in heat exchange equipment. Afterwards, a simplified mathematical model of the heat exchanger was compiled. Such an analytical form makes a solution convenient for engineering calculations. Numerical calculations based on this model were compared with the experimental data. Heat transfer intensity of materials with different porosity was compared.

Use of porous materials in heat exchangers makes them more efficient in a smaller form-factor. Heat exchangers based on porous materials have uses in various industries, e.g. in power engineering. The latter currently relies on steam-to-water heat exchangers that load the environment. One promising way to make heat exchangers more eco-friendly is to use porous materials. An experimental setup was made to study heat transfer in porous materials. The setup enabled the research team to find the degree of cooling the hot coolant (water) passing through a porous heat exchanger. For comparison, experiments also involved a second heat exchanger (tubular, non-porous). The paper presents the installation diagram and the experiment methodology. It also reports the processed experimental data, draws conclusions, and suggests further experimentation.