Heat Exchanger System Research Articles

Experimental and numerical study on cooling performance of a novel earth-to-air heat exchanger system with an inlet plenum chamber

Previous studies have focused on the horizontal buried pipe section regarding the performance improvement of the earth-to-air heat exchanger, showing limited attention paid to the vertical air inlet section. In this study, we proposed a novel earth-to-air heat exchange system utilising an inlet plenum chamber (IPC-EAHE) to pre-treat the outdoor air in the inlet section. To evaluate its cooling performance, a numerical model was developed and validated based on a field experiment. The results showed a good agreement between simulated and experimental data, with a maximum absolute relative error of 4.43 % for the outlet air temperature. Then comparative studies between the IPC-EAHE and traditional EAHE are conducted under three airflow rates. Results indicated that the IPC-EAHE has a lower and more stable outlet air temperature than traditional EAHE. Compared to the traditional EAHE, the IPC-EAHE reduces the fluctuation of outlet air temperature by 53.13 %, 29.84 %, and 26.60 % under the airflow rates of 190 m3/h, 380 m3/h, and 570 m3/h, respectively. This improves the free cooling potential of EAHE for buildings. Moreover, the IPC-EAHE can reduce the buried pipe length by around 60.30 %, 53.0 %, and 50.0 % for three airflow rates, respectively. The friction resistance loss of the IPC section is at least 20 % less than that of the traditional EAHE vertical inlet section. The above results demonstrate that the IPC-EAHE offers greater renewable energy utilization efficiency and less buried pipe length than the traditional EAHE.

Multi-objective energy and exergy optimization of hybrid building-integrated heat pipe photovoltaic/thermal and earth air heat exchanger system using soft computing technique

This research is dedicated to the numerical assessment of the performance of a novel system that uses solar and geothermal energy at the same time, which is capable of heating/cooling the outside air before it enters the air conditioning system of a building and supplying the required electricity for the building. The desired system consists of a photovoltaic/thermal-heat pipe (PVT-heat pipe) unit and an earth-air heat exchanger (EAHE). To cool the outside air in hot seasons of the year, the air is passed through the EAHE system and the exhaust air from building is used to cool the photovoltaic panels. Outside air heating in cold seasons is also possible by passing air through the PVT-heat pipe and EAHE systems. The genetic algorithm-based two-objective optimization is used to determine the necessary conditions to simultaneously maximize the annual useful energy and exergy yields of the hybrid system. The performance metrics of the optimal system are compared with the corresponding values of the PVT-EAHE unit. Outcomes revealed that the annual useful energy output of the PVT-heat pipe-EAHE system (93925.6kWh) is less than the PVT-EAHE system (96448.6kWh), while the PVT-heat pipe-EAHE system is able to produce more exergy (10904.5kWh) than the PVT-EAHE system (10015.5kWh).

From Generalized Hamilton Principle to Generalized Schrodinger Equation

The Hamilton principle is a variation principle describing the isolated and conservative systems, its Lagrange function is the difference between kinetic energy and potential energy. By Feynman path integration, we can obtain the standard Schrodinger equation. In this paper, we have given the generalized Hamilton principle, which can describe the heat exchange system, and the nonconservative force system. On this basis, we have further given their generalized Lagrange functions and Hamilton functions. With the Feynman path integration, we have given the generalized Schrodinger equation of nonconservative force system and the heat exchange system.

Investigations of protracted finned double pipe heat exchanger system for waste heat recovery from diesel engine exhaust

The need for energy and material savings, as well as environmental concerns, have helped to increase the demand for high efficiency heat exchangers in the modern era. In practice, a heat exchanger or the direct ejection of the hot working fluid is used to recover the waste heat from a heat engine or thermal power plant into the environment. Waste heat of a heat engine or power plant is recovered to the environment via a heat exchanger or by direct ejection from the hot working fluid. In many situations, waste heat recovery removes or greatly reduces the necessity for additional fuel energy input to achieve this goal. The double pipe heat exchanger equipment is taken in this research, heat from engine exhaust recovers due to its superior qualities. The design characteristics of the heat pipe will be changed in order to increase overall efficiency by studying the concepts of various authors. Different design parameters for a double pipe heat exchange system as well as different working fluid-flow rates are tested with the suggested device. Additionally, ANSYS performs CFD for the proposed heat exchanger system in order for the results to support the experimental findings.

Investigation of heat transfer during magnetohydrodynamic flow of liquid metal in the “pipe in channel” heat exchange system

Investigation of heat transfer during magnetohydrodynamic flow of liquid metal in the “pipe in channel” heat exchange system

DEVELOPMENT OF DISTRIBUTED GENERATION OF HEAT AND ELECTRIC ENERGY BASED ON EDDY CURRENT GENERATORS-UTILIZERS

The article analyzes ways of transforming Ukraine's energy system based on the "Smart Grid" concept with the implementation of distributed generation projects. The expediency of using new tools for the decentralization of thermal and electrical energy sources as a component of small-scale energy, focused on renewable types of uncertified biofuel of local origin, is substantiated. The energy, economic, ecological and social significance of the introduction of systems of thermochemical destruction of bio-waste with the help of jet-vortex generators-utilizers in energy-intensive technologies has been proven. New approaches to the process of heat energy generation in energy-intensive processes of the agro-industrial complex are proposed using the example of grain drying. Thermal engineering means of thermochemical destruction of biowaste, heat exchange system and disposal of combustion products have been developed. A full cycle of production tests of automated jet-vortex generators-utilizers was carried out, taking into account non-deterministic technological parameters (temperature, humidity, productivity, physico-chemical properties of fuel). The cost of thermal energy in technological processes of grain drying is 5...7 times lower than traditional hydrocarbon. Given the presence of a functional heat exchanger, the drying process takes place with heated clean air, which has a positive effect on the quality indicators of the grain. Taking into account the challenges that exist in the electric power industry of Ukraine, a project of a cogeneration plant based on a generator-utilizer and an air turbine is proposed, which, with the help of a heat exchanger and a compressor, converts part of the thermal energy into mechanical energy. With the help of an electric machine converter, electricity is produced, which meets the needs of the heat engineering module of the installation. The total efficiency of the cogeneration plant is about 80 %.

Determinação de água exógena em suco de uva através da razão isotópica do 18O/16O

Abstract The consumption of grape juice has been growing significantly, so its quality is becoming an issue of great importance, both for the consumer and for the industry. However, identifying adulteration in juice is a great challenge and requires a reliable analytical process. The isotope ratio (18O/16O) is an important tool to determine the addition of exogenous water in beverages, however, there is no official method for juice in Brazil. This study aimed to develop and validate a method for detecting exogenous water in grape juice through isotopic analysis of 18O/16O. The development and validation of the analytical method were performed using Isotope Ratio Mass Spectrometry (IRMS). The effect of temperature and evaporation of δ18O in experimental juices was evaluated, and reference values were found for juices based on the δ 18O of musts. The influence of the juice industrial production process on 18O values was verified, and commercial juices were evaluated in relation to the values of reference regarding the addition of water. The temperature and evaporation parameters did not influence the results of the 18O of the juice, as they presented differences lower than the method uncertainty. The heat exchanger system did not influence the proposed method. The reference values for juice can come from the musts, without affecting the interpretation of the final results. Of the thirty real juices analyzed, nine had exogenous water, three proved to be reconstituted juices and eighteen were considered to have no exogenous water. The method proposed and validated in this study presented values for the limit of detection (LOD) of 0.24‰, the limit of quantification (LOQ) of 0.97‰ and measurement uncertainty of 0.71‰, proving to be effective for the detection of exogenous water in grape juice, through of the analysis of the isotopic ratio of 18O/16O by IRMS.

PERFORMANCE OPTIMIZATION OF SUPERCRITICAL CO2 GAS HEATER IN A BIOMASS-CO2 POWER GENERATION SYSTEM

A comprehensive computational fluid dynamics (CFD) simulation model was developed in the current research to simulate a shell-and-tube supercritical CO<sub>2</sub> gas heater used in a biomass-CO<sub>2</sub> power generation system. The model was based on the actual design of the heat exchanger and relevant operational parameters. The simulation model was validated using manufacturer operational data and empirical correlations before being utilized to evaluate the performance of the heat exchanger and its related system under various operating conditions and heat exchanger designs. The results of the simulation demonstrate that the heating capacity of the heat exchanger can be increased differently by increasing the flue gas temperature, flue gas mass flow rate, and CO<sub>2</sub> mass flow rate. Furthermore, there is an optimal CO<sub>2</sub> pressure ratio that can improve the system's thermal efficiency. Decreasing the distance between hot fluid pipe inlet and cold fluid outlet ports, as well as hot fluid pipe outlet and cold fluid inlet ports, can effectively enhance the heating capacity of the shell-and-tube heat exchanger and its associated system. In quantity, with the new heat exchanger design, the heating capacity exhibits maximumly 9.2% average improvement, while the associated system thermal efficiency can have an average 6% enhancement with varied flue gas mass flow rates. Based on the CFD simulation outcomes, recommendations for enhancing the heat exchanger designs and system controls have been identified.

COMPARATIVE ANALYSIS OF EXERGETIC EFFICIENCY OF HEAT RECOVERY SYSTEMS OF BOILER PLANTS

The paper presents the results of a comparative analysis of the exergetic efficiency of heat recovery systems of boiler plants. The need to ensure the efficient operation of heat recovery systems for various purposes determines the importance and relevance of research conducted in this field. The purpose of the work is to increase the exergetic efficiency of heat recovery systems of various purposes. The results of solving the tasks necessary to achieve the set goal are given: - submit heat utilization systems of various purposes in the form of structural diagrams with the identification of exergetic flows of heat carriers; - choose exergetic efficiency evaluation criteria for heat recovery systems of various purposes, calculate their values and conduct a comparative analysis; - develop recommendations for the use of heat recovery systems for various purposes, taking into account the specifics of their application. For research, a complex methodology was used, which combines structural-variant methods of exergetic analysis with methods of presenting exergetic balances in matrix form. Three types of heat recovery systems with different numbers of consumers of recovered heat were considered. Structural diagrams of heat recovery systems of various purposes with identification of exergetic flows of heat carriers between individual discrete elements have been developed. Exergetic losses, thermal exergetic criterion and exergetic efficiency were selected as criteria for evaluating exergetic efficiency. Their values were obtained for heat recovery systems and their elements at different values of the relative power of the boiler. The largest exergy losses occur in the water-heating heat exchanger, smoke extractor and pumping system, the smallest - in the air-heating heat exchanger and gas heater. An increase in the relative power of the boiler leads to an increase in the relative contribution of the exergy losses of the water heating heat recovery system, as well as the pumping system and the pipeline system to the total exergy losses in the heat recovery system. It has been established that increasing the number of consumers of recovered heat in the heat recovery system and using rational ways of reducing total exergy losses increases the efficiency of heat recovery systems. Further developments in this field will allow to increase the exergetic efficiency of heat recovery systems for various purposes.

Global sensitivity analysis of a generator-absorber heat exchange (GAX) system’s thermal performance with a hybrid energy source: An approach using artificial intelligence models

• Temperature, heat and flow measurements of an experimental GAX cycle. • Evaluation of artificial intelligence (AI) techniques for multivariate modeling. • Artificial neural networks represent the GAX system with the best accuracy. • AI model coupled to the PAWN method for a global sensitivity analysis of GAX cycle. • COP is affected the most by the temperature measured at the generator inlet. Generator-absorber heat exchange (GAX) systems represent a promising alternative to substitute environmentally harmful refrigeration devices based on conventional vapor compression, as long as a proper analysis of thermal performance and the complex interactions of heat transfer that occur into GAX cycle is taken in consideration. In this research, a cooling process based on a GAX system that uses ammonia-water working fluid and a hybrid source (natural gas-solar) is studied to analyze the variables that affect the system’s thermal performance. The work’s novelty is the hybridization between artificial intelligence (AI) modeling and the global sensitivity analysis (GSA) developed with the PAWN method. Experimental data was obtained from a system with a cooling capacity of 10.5 kW (3 Ton), designed to work at heat source temperatures of 200 °C. The measured variables were the temperatures at generator, heat at evaporator, and working fluid volumetric flow. Three AI techniques (artificial neural networks, genetic programming, and support vector machines) were evaluated for modeling the thermodynamic cycle. Results obtained from the PAWN method applied to the artificial neural network, since it was the best AI model, indicates that the operational parameters with a greater impact in the system’s performance are the inlet temperature at the generator (30.7 %) and the heat measured at the evaporator for NH 3 (27.4 %), for the first output COP N H 3 . For the second output COP H 2 O , the inlet temperature at the generator (32.5 %) and the and heat measured at the evaporator for H 2 O (26.7 %), have a greater impact for such output. The proposed IA-GSA methodology contributes to the development of operational decision-making related to instrumentation, operation performance, and corrective and/or preventive maintenance actions of GAX systems. The developed thermal performance model has potential for implementation in embedded systems (smart sensors) as a critical element in control and optimization strategies to improve the performance of these cycles.

Experimental investigation on an auto-cascade quasi two-stage compression heat pump system

• A novel auto-cascade quasi two-stage compression heat pump system is proposed. • Experimental research was conducted on the novel system with HFC32/HFO1234ze(E). • The novel system has a 6.2–9.0% higher COP than the flash tank system. • The novel system has a 1.8–3.5% higher COP than the internal heat exchanger system. Refrigeration and heat pump systems consume approximately 20% of global electricity. The (quasi) two-stage compression and auto-cascade cycle configuration are effective approaches to save energy for vapor compression refrigeration and heat pumps because the former can reduce throttling irreversibility and the latter takes advantage of the concentration separation of zeotropic refrigerants to reduce the pressure lift of the system. Accordingly, a new auto-cascade quasi two-stage compression system (ACQT) used for building heating is proposed in this study. An experimental setup was built. The performance of the proposed system charging with a 0.5/0.5 mole fraction of HFC32/HFO1234ze(E) was experimentally explored by comparing it with a quasi two-stage compression system with an internal heat exchanger (IHXQT) and that with a flash tank (FTQT). The results indicate that the ACQT improves the coefficient of performance (COP) by 6.2–9.0% compared to the FTQT while maintaining the same heating capacity. Moreover, the ACQT achieves a 1.8–3.5% higher COP than the IHXQT while maintaining the same heating capacity.

Transfer matrix analysis of a string heat exchange system for a semi-infinite plate

Transfer matrix analysis of a string heat exchange system for a semi-infinite plate

Radiant capillary heat exchangers – power calculation for optimal heating and cooling

The issue of switching to renewable energy sources becomes very actual and it is important not only to change the energy source, but also the reduce the final energy needs by improving the energy efficiency of buildings and usage of efficient heating systems. Heat pumps as the most popular renewable energy source are widely used, but their energy efficiency is depending on temperature of the supplied energy carrier. The most efficient are radiant capillary heat exchangers with a large surface area and a low temperature, which typically does not exceed 30°C. Another advantage of radiant capillary heat exchangers is the possibility to operate them in both - heating and cooling modes. Unlike the underfloor heating solution, where the role of thermal convection is very important, the built-in radiant capillary heat exchanger systems provide the energy mainly due to thermal radiation. This study explores two modelling approaches for determination of required power and corresponding area of radiant capillary heat exchangers to be installed in a room to provide heating and cooling: simplified approach, which allows to create the heat balance with a minimum amount of input data and a precise standard-based approach. Calculations were made for three different rooms with variable glazing area and spatial orientation using both approaches. Analysis of the calculation results shows the limits of the simplified method, which overestimates heating need and underestimates cooling need, and the main reason for such differences is simplification of room orientation and subsequent solar heat gains. As the calculated cooling power is less than heating power, therefore the heating estimation is sufficient to estimate the amount of radiant capillary heat exchangers in small/medium rooms for providing both heating and cooling in the climatic conditions of Riga. The use of complex, comprehensive modelling approaches is necessary for rooms with large glazed areas, where the simplified method gives incorrect estimations.

The use of pinch analysis technology to assess the energy efficiency of oil refining technologies

Exergy pinch-analysis of the heat exchange system of the furnace of the primary oil refining unit is carried out. Composite curves are created using a mathematical model, and then the optimal structure of the heat exchange with minimal exergy losses is constructed. Exergy pinch analysis allows revealing the magnitude and location of exergy losses. In the heat exchange system of the furnace exergy loss is 9 MW. It is possible to increase the efficiency of the furnace by 18.5%. An additional heat exchanger connecting it to the oil stream is introduced for rational use of residual exergy.

IMPROVING THE THERMAL PERFORMANCE OF A CONCENTRIC-TUBE HEAT EXCHANGER SYSTEM UTILIZING A NOVEL HYBRID MAGNETIC NANOFLUID

Hybrid magnetic nanofluid is the phase involved in a suspension of a mixture of nanometer-sized particles in traditional fluids. The most conspicuous attributes of this fluid comprise improved heat characteristics, for instance, convective heat transfer coefficient, compared to the conventional fluid. Hybrid magnetic nanofluid of iron oxide and ferric oxide with a mixture proportion of 50:50 was added to distilled water (DW). The impact of forced convective heat transfer coefficient in turbulent flow was estimated by employing parallel- and counter-flow concentric-tube heat exchanger systems. The forced convective heat transfer coefficient of the hybrid magnetic nanofluids was calculated applying empirical equations corresponding to the experimental results. Furthermore, the system's performance with (Fe<sub>3</sub>O<sub>4</sub>@Fe<sub>2</sub>O<sub>3</sub>/DW) 0.5 wt.% hybrid magnetic nanofluid with (Fe<sub>3</sub>O<sub>4</sub>/DW), (Fe<sub>2</sub>O<sub>3</sub>/DW) 0.3 wt.% regular magnetic nanofluids, and distilled water was compromised. The determinations reveal notable improvement in the convective heat transfer coefficient in both parallel- and counter-flow regimes in the case of hybrid magnetic nanofluid compared to the regular ones and base fluid, the highest enhancement in the overall convective heat transfer coefficient was up to 49.8% compared to distilled water at 31,689 Reynolds number and 18.46% and 20.5% compared to Fe<sub>3</sub>O<sub>4</sub>/DW and Fe<sub>2</sub>O<sub>3</sub>/DW regular magnetic nanofluids at 36,215 Reynolds number in the parallel-flow regime. Moreover, the Nu number was improved in the case of the hybrid magnetic nanofluid reaching maximum values up to 38.1%, 13.2%, and 14.8% corresponding to distilled water and regular magnetic nanofluids, respectively. The augmentation in the heat transfer utilizing hybrid magnetic nanofluids was caused by 22.47% thermal conductivity improvement compared to base fluid.

Influence of frequency and intensity of bilateral audible sound waves on heat transfer performance of air-to-air heat exchange systems

To enhance the air heat transfer performance, this study applied the bilateral audible sound waves to an air-to-air heat exchanger. The effect of the frequency and intensity of sound waves on heat transfer performance was investigated from the viewpoint of flow instability and heat flux, and the sound power efficiency was also explored to reveal the efficiency of sound waves on the heat transfer performance. The results showed that the flow instability intensified with the increase in sound pressure level (SPL) and decrease in frequency, which was reflected by the distribution of turbulence kinetic energy. The change in sound waves has different effects on the turbulence kinetic energy at different locations, and the directivity distribution characteristics of the turbulence kinetic energy inside and outside the heat tube caused similar directivity distribution characteristics of the heat flux, in which the maximum value of the heat flux was located perpendicular to the flow direction. Additionally, the heat flux at different locations increased with an increase in SPL and a decrease in frequency. The heat transfer performance was relatively superior when the SPL was higher than 120 dB and the frequency was lower than 100 Hz, and a decrease in frequency could increase the sound power efficiency. This study can guide the application of sound waves in the heat transfer enhancement of air-to-air heat exchange systems.

Numerical simulation of stand-alone photovoltaic integrated with earth to air heat exchanger for space heating/cooling of a residential building

Earth-to-air heat exchanger is one of the efficient energy-saving approaches to meet the heating/cooling requirement of residential buildings/greenhouses. In this work, a comprehensive numerical and statistical approach using the response surface method aiming at the integration of stand-alone photovoltaics with earth-to-air heat exchangers is discussed for the coordinates of Delhi. For parametric optimization of the earth-to-air heat exchanger, statistical tool, and response surface methodology is used by taking ground temperature profile and weather data into account. Among the primary parameters, the diameter of the pipe is found to be the most significant parameter. Optimized pipe diameter of 0.2 m, pipe length of 70 m, and air velocity of 7 m/s have yielded a total energy gain of 8116.7 kWh/year. Evaluation of herein designed hybrid system has estimated CO2 mitigation of 16.18 tons/year which in turn has evinced the carbon credit value to US$ 336.86/year. Calculations exhibit a simple payback period of approx. 5 and 10 years for one day and 2 days autonomy respectively when compared with the electricity cost of diesel generators for rural areas. With 24 h grid availability, the simple payback period with a photovoltaic system gets reduced to 4–5 years in urban areas as it doesn't require any battery bank. This kind of self-sufficient hybrid system is an eco-friendly and sustainable energy solution for altogether rural and urban areas. This work provides an effective blueprint of commercially viable photovoltaic integrated with earth-to-air heat exchanger systems for households.

Optimasi unjuk kerja pada sistem pendinginan adsorpsi dengan siklus pemanasan-ulang kombinasi

The adsorption refrigeration system is a cooling system that offers several benefits, including being environmentally friendly due to the very small amount of global warming effect given, the lack of potential for ozone depletion, the low energy consumption of its operation, the low heat source used in its operation and good for reducing gas emissions on earth. This paper describes a combined reheating adsorption refrigeration system with three heat exchangers, as well as operating modes. The operation of the adsorption refrigeration system with combined reheating is schematically described with operational modes and diagrams. This adsorption cooling system is made up of three heat exchangers (H), one evaporator, and one condenser. The combination cycle is intended for heat exchanger systems that operate in a reheat cycle (H1 and H2) and a non-reheating cycle (H3). This paper also discusses system cycle time optimization. Research to get the optimum value of cycle time in this system is still rarely done and therefore optimization of cycle time is carried out on the system to get the best performance. The PSO (particle swarm optimization) program is paired with the MATLAB program to simulate the performance of the system under discussion while also enhancing its performance. The goal of this work is to use simulation to determine the optimal system performance versus the overall cycle time, which includes adsorption/desorption time, pre-cooling and pre-heating time as well as mass recovery time. Getting the best value for the entire cycle time is made possible by fusing the simulation of the system's process performance with performance optimization. As a results, the greatest increase in the optimization results' performance value occurs at a heat source temperature of 55ºC with a longer time to achieve optimal performance.

Numerical Simulation of Geothermal Reservoir Reconstruction and Heat Extraction System Productivity Evaluation

The key to ensuring the economic feasibility of EGS mainly includes two points. On the one hand, it is necessary to ensure the connectivity of the artificial fracture network; on the other hand, it is necessary to determine the most efficient geothermal energy exploitation mode. Most previous studies have only focused on one of the points. To restitute the entire geothermal energy development process, the two parts should be combined to conduct research. In this study, a random fractured medium model was established based on the TOUGH2-BIOT simulation program and the whole process of reservoir stimulation was analyzed. According to the results of reservoir stimulation, different geothermal energy exploitation schemes are set up, and the heat transfer efficiency of the conventional double vertical wells, the horizontal wells, and the double-pipe heat exchange system are comparatively analyzed. The results show that reservoir reconstruction is mainly divided into three stages: In the first stage, the hydraulic aperture of the conducting fractures reaches the maximum value; in the second stage, the non-conductive fractures overcome the in situ stress and become conducting fractures; in the third stage, the rock in the reservoir undergoes shear failure, the fractures expand and connect, and finally, a fracture network is formed. After each stage, the volume of the enhanced permeability area is approximately 10,000, 21,000, and 33,000 m3, respectively. After 30 years of exploitation, the outlet temperature and thermal power output of conventional double vertical wells are the highest, while the horizontal wells have the highest heat extraction ratio. The temperature of a production well in the conventional double vertical wells model, horizontal wells, and double-pipe heat exchange system is 101 °C, 93.4 °C, and 91.6 °C, a decrease of 41.2%, 45.7%, and 46.7%, respectively. The thermal power output is 6.67 MW, 6.31 MW, and 6.1 MW, a decrease of 39.4%, 42.6%, and 44.5%, respectively. The heat extraction ratio of the horizontal wells is 2% higher than the double-pipe heat exchange system and 6.5% higher than the conventional double vertical wells.

Thermohydraulic studies of alkali liquid metal coolants for justification of nuclear power facilities

The paper presents and discusses the results of experimental and computational studies obtained by the authors on hydrodynamics and heat exchange in fuel assemblies of the alkali liquid metal cooled fast reactor cores, and experimental data on hydrodynamics of flow paths in the heat exchanger and reactor header systems. Investigation results are presented on in-tank coolant circulation obtained using a well-developed theory of approximation simulation of the nonisothermic coolant velocity and temperature fields in the fast neutron reactor primary circuit and demonstrating stable stratification and thermal fluctuations in the coolant. Results are presented from experimental and computational simulation of the alkali liquid metal boiling process based on fuel assembly models during an emergency situation caused by an operational occurrence involving simultaneous loss of power for all reactor coolant pumps and the reactor scram rod failure. Objectives are formulated for further studies, achieving which is essential for the evolution of the liquid metal technology, as dictated by the need for the improved safety, environmental friendliness, reliability and longer service life of nuclear power facilities currently in operation and in the process of development.