Heating Technology Research Articles

A Novel Non-Resonant Full-Bridge Multi-Output Topology for Domestic Induction Heating Applications

Induction heating technology plays a significant role in heating applications with its high efficiency, fast response, and precise control ability. Traditional resonant inverter-based systems face problems such as complexity, lack of flexibility, and low efficiency in multi-load situations. To overcome these issues, a new non-resonant full-bridge multiple-output inverter topology using silicon carbide (SiC) semiconductor devices is presented. While the system is simplified by eliminating resonant components, efficiency is increased thanks to SiC devices. In the study, a coil design methodology focusing on coil resistance and inductance is presented to optimize energy transfer and maximize system performance. Load-sensing and advanced frequency-modulation techniques are integrated to provide precise and independent power regulation in multi-loads. Thus, the efficiency of energy distribution and system robustness are increased. The proposed topology offers heating performance that provides homogeneous heat distribution. The developed prototype was proven to operate reliably with high efficiency under different load conditions and was suitably applied for domestic induction heating applications. An efficiency of 96.78% was achieved at a 50 kHz operating frequency and 2000 W power level.

Identification of characteristic flavor compounds in steamed and baked Hu sheep mutton.

The advancement in heat treatment technology has spurred the innovation of various smart cooking appliances, including the steam roaster. Consequently, the technique of synchronized steaming and baking has emerged as a novel form of thermal processing. Therefore, the effects of baking, steaming, steaming-baking heating modes on the flavor of Hu sheep mutton were evaluated. Main sensory descriptors were identified by descriptive sensory analysis. The results showed that SMM presented a relatively strong muttony profile, BKM presented a pronounced profile of burning, smokiness, and baking, while the flavor of SMM was situated intermediary between these two profiles. By SPME-GC-MS, 28 volatile chemicals with OAV > 1 were found. The correlation network analysis revealed relationships between the aroma compounds and sensory descriptors, namely "smoky and baked" (2,5-dimethylpyrazine, dimethyl trisulfide), "muttony" (hexanal, 2-heptenal), "fatty" ((E)-2-octenal), "meaty" (1-octen-3-ol), "burned" and "greasy" (3-methylthiopropionaldehyde, dimethyl disulfide). Meanwhile, analysis of 5'-nucleotides and FAAs revealed 8 characteristic taste compounds with TAV > 1. Moreover, multivariate analysis showed that 2-pentylfuran, E-2-octenal and 2-heptenal, 2,5-dimethylpyrazine might contribute more to the flavor of steamed-baked, steamed, baked Hu sheep mutton, respectively.

Biomass Gasification as a Viable Alternative for Small-scaled Combined Heat and Power Technologies in Remote Communities in Canada

Biomass Gasification as a Viable Alternative for Small-scaled Combined Heat and Power Technologies in Remote Communities in Canada

Novel Inlay Methodology with Thermoplastic and Heating System for Durable Road Markings

Road markings, such as lane dividers and pedestrian crossings, are integral in ensuring the safety of road users. However, traditional markings frequently exhibit limitations, including short lifespans, diminished visibility, and significant maintenance costs, particularly as traffic volumes increase. To address these persistent challenges, this study presents a thermoplastic road marking system that combines material innovation and advanced application techniques. Central to this approach is the portable heating system, equipped with ceramic heaters and precise temperature controls, which facilitates uniform heating while mitigating fire risks. The thermoplastic blend, processed into pre-formed sheets, was integrated with this heating technology. Together, these components enabled a two-phase process, engraving asphalt surfaces followed by sheet integration, that ensured robust adhesion and seamless bonding. Field trials conducted on various asphalt types validated the system’s reliability, demonstrating its durability under traffic loads and consistent visibility. By integrating durable materials with advanced application methods, this methodology significantly enhances the efficiency, longevity, and safety of road markings. It presents a practical and scalable solution for modern infrastructure needs. Future research will focus on evaluating the system’s long-term performance under extreme weather conditions to further optimize its applicability.

Microwave installation for continuous heat treatment of poultry muscle stomachs

BACKGROUND: The volume of processed chicken muscle stomachs as meat raw materials in Russia per year is 0.1-0.15 million tons. Therefore, the implementation of microwave technology for heat treatment of such raw materials is relevant. AIM: The aim of the study was to develop a radio-hermetic installation with a conical resonator for heat treatment of the muscular stomachs of birds in continuous operation at high electric field strength in farm conditions. METHODS: The raw material is chicken muscle stomach. The innovative idea is that the muscular stomach as a multicomponent raw material, pre-crushed on an electrically driven grating disc, is ground against the abrasive coils of an electrically driven screw during dielectric heating in continuous mode in a conical resonator, providing high electric field strength and electromagnetic safety by truncating the cone at the critical surface level. The study of the heating temperature of raw materials was carried out using an infrared thermometer Testo 845, and the distribution of the electric field in the resonator was carried out in the CST Microwave Studio 2018 program. RESULTS: In a conical resonator, where a grating disk is installed under the base with a gap of no more than a quarter of the wavelength, a fluoroplastic electric drive screw with screws coated with an abrasive material is. The diameters of the screws change with the change in the diameter of the resonator. The resonator is truncated at the critical section level. The results of a study of the dynamics of dielectric heating of chicken muscular stomach at specific capacities of 3.3-7 W/g show that they will cook in 3-4 minutes. The specific energy costs for heat treatment of raw materials in an installation with a power consumption of 4.15 kW and a capacity of 30 kg/h are 0.14 kWh/kg. The intrinsic Q−factor of the resonator is 77200, the electric field strength is 4-5 kV/cm.

Complete absorption of 2.45 GHz microwaves by multiple-conductive-layered system and application in heating technology

Complete absorption of 2.45 GHz microwaves by multiple-conductive-layered system and application in heating technology

A program for modeling the RF wave propagation of ICRF antennas utilizing the finite element method

Abstract Controlled nuclear fusion represents a significant solution for future clean energy, with Ion Cyclotron Range of Frequency (ICRF) heating emerging as one of the most promising technologies for heating the fusion plasma. This study primarily presents a self-developed 2D Ion Cyclotron Resonance Antenna Electromagnetic Field Solver (ICRAEMS) code implemented on the MATLAB platform, which solves the electric field wave equation by using the finite element method, establishing Perfectly Matched Layer (PML) boundary conditions, and post-processing electromagnetic field data. This code can be utilized to facilitate the design and optimization processes of antennas for ICRF heating technology. Furthermore, this study examines the electric field distribution and power spectrum associated with various antenna phases to investigate how different antenna configurations affect electromagnetic field propagation and coupling characteristics.

Design and Fabrication of Multi-Magnetron Microwave Oven for High-Temperature Applications

This article examines the design, manufacture, and performance of multi-magnetron ovens capable of reaching high temperatures. Firstly, an appropriate waveguide was simulated, and the production process was completed. Then, the proposed designs for multi-magnetron ovens were simulated, and appropriate dimensions were suggested. It was reported that the average power density (PD) value of the produced multi-magnetron oven was 0.37 mW/cm², which indicates its performance and efficiency. This value was found to be compliant with standards and safe for human use. The main objective of our study was to demonstrate that waveguides can reach high temperatures at the center of the oven without affecting each other. In this context, it was observed that the temperature created by magnetrons operating in single, double, triple, and quadruple modes gradually increased at the center of the oven. The simulation results supporting this showed that the S21 parameter was -177 dB. The design proposed and applied in our study was efficient, easy to produce, safe for human use, low cost, and usable in commercial and academic studies for reaching high temperatures. Overall, the multi-magnetron oven design proved to be a successful and practical solution for applications requiring high temperatures, showcasing its potential for both industrial and research purposes. The findings of this study contribute valuable insights into the development of advanced heating technologies, demonstrating significant improvements in efficiency and safety for high-temperature applications.

Enhancement of Fracture Toughness of NiTi Alloy by Controlling Grain Size Gradient.

Fracture toughness is a critical indicator for the application of NiTi alloys in medical fields. We propose to enhance the fracture toughness of NiTi alloys by controlling the spatial grain size (GS) gradient. Utilizing rolling processes and heat treatment technology, three categories of NiTi alloys with distinct spatial GS distributions were fabricated and subsequently examined through multi-field synchronous fracture tests. It is found that the one with a locally ultra-high GS gradient (20 nm-3.4 μm) has significantly enhanced fracture toughness, which is as high as 412% of that of the normally distributed nano-grains with an average GS of 8 nm and 178% of that of the coarse-grains with an average GS of 100 nm. Theoretical analysis reveals that in such a gradient structure, phase transition in the coarse-grained matrix greatly absorbs the surface energy of subcritical and stable propagation. Meanwhile, the locally non-uniform GS distribution leads to deviation and tortuosity of the crack path, increasing the critical fracture stress. Furthermore, the nanocrystalline clusters distributed in the form of network nodes reduce the stress intensity factor due to their higher elastic modulus compared to the coarse-grained matrix. This work provides guidance for developing new gradient nanostructured NiTi alloys with high fracture toughness.

ОБОСНОВАНИЕ ПРИМЕНЕНИЯ НОВОЙ ТЕХНОЛОГИИ ПРОИЗВОДСТВА ШПИНТОНОВ

This study objective is to analyze the effectiveness of using the technology of tail suspension of cars as a way to increase the reliability and comfort of movement in railway transport. To achieve this goal, the following task was defined: identification and analysis of internal defects that are the causes of product rejection, and the subsequent development of recommendations for their elimination. The main research method is the analysis of current operating procedure of manufacturing parts, the study of materials and methods of their processing used to strengthen tails. The priority is to identify the key factors contributing to increasing the durability of the tail assembly through the use of reinforcing technology. Both theoretical analysis of existing scientific papers on this topic and practical experiments on stress tests are used as research methods. The novelty of the work is in offering a more environmentally friendly product processing technology, as well as confirming the possibility of replacing the tail material with a more cost-effective one. It is worth noting that the issue of ensuring the quality of truck tails of subway cars, the ecological purity of the heat treatment process, and cost reduction is being solved through a new heat treatment technology – quenching with a fast-moving stream of water and replacing 40X alloy steel with 35 carbon steel without reducing operational properties. As a result, the proposed measures contribute to improving the manufacturing quality of tail assemblies and reducing the percentage of their rejection at the production testing stage.

Numerical simulation of cementing seal integrity during electric heating of oil shale

Electric heating technology is a vital method for in-situ modification and exploitation of oil shale. This process subjects the wellbore and cement sheath to prolonged exposure to high temperature and pressure environments, posing significant challenges to the integrity of the cementing seal. To investigate the thermally induced changes during the electric heating process of cement sheath and oil shale, a combined model of cement sheath and oil shale was established using the discrete element method. The combined model was calibrated based on macroscopic mechanical experiments of cement sheath and oil shale. Subsequently, the thermal-mechanical coupling problem and thermal cracking phenomenon of the combined model under high temperature and high pressure environments were examined. The results revealed that thermal cracks begin to emerge at the onset of heating at around 150 °C, leading to a decrease in compressive strength and elastic modulus of the combined body. As the temperature reaches 400 °C to 500 °C, the number of thermal cracks peaks. The underground high-pressure environment impedes the thermal expansion of combined body particles, thereby inhibiting the development of thermally induced cracks. The addition of steel fibers to the cement sheath significantly reduces thermal cracking and effectively enhances the sealing performance of the cement sheath.

Development and pasteurization of in-packaged ready-to-eat rice products prepared with novel microwave-assisted induction heating (MAIH) technology

Development and pasteurization of in-packaged ready-to-eat rice products prepared with novel microwave-assisted induction heating (MAIH) technology

Effects of rapid infrared radiation heating on the warping deformation and mechanical properties of selective laser melted Co-Cr dental alloy.

Infrared radiation heating (IRH) technology has been innovatively applied to the annealing of selective laser melted (SLM) cobalt chromium (Co-Cr) frameworks. However, previous studies have not reported the effects of IRH on the warping deformation and mechanical properties of these frameworks. The purpose of this in vitro study was to investigate the effects of IRH on the warping deformation and mechanical properties of dental SLM Co-Cr alloy and to evaluate its potential applications in dental restorations. Two types of specimens, bone-shaped tensile specimens and warping deformation specimens (cantilever beam structures), were fabricated by SLM, followed by annealing using IRH and general furnace heating (GFH). The specimens were divided into 4 groups (n=6) based on the applied heat treatment method and build direction (IRH-XY; IRH-Z; GFH-XY; GFH-Z). The cantilever beam support structure of the warping deformation specimen was cut using wire cutting, and the warping deformation was measured using a digital image correlation optical extensometer. Tensile tests were used to evaluate mechanical properties, with the fracture characteristics being observed using a scanning electron microscope (SEM). A micro-Vickers hardness tester was used to measure the microhardness. The microstructures were analyzed using a metallographic microscope. All data were analyzed using a 1-way ANOVA and the Tukey Honestly Significant Difference test (α=.05). The surfaces of the SLM Co-Cr warping deformation specimens treated with IRH showed slight oxidation, while those treated with GFH exhibited a dark black appearance. No significant difference was found in deformation between the IRH group (0.412 ±0.039 mm) and the GFH group (0.379 ±0.070 mm) (P>.05). The elongation of the longitudinally built specimens was significantly higher than that of their transversely built counterparts (P<.05), while the yield strength showed an opposite trend. The longitudinally built specimens demonstrated ductile fracture characteristics, while the transversely built specimens displayed quasi-cleavage fractures. The specimens treated with IRH exhibited comparable tensile strength and microhardness with the GFH-treated specimens, with no statistically significant differences (P>.05). IRH treatment resulted in finer grains in the SLM Co-Cr alloy. Many fine second-phase particles precipitated from the matrix in the longitudinally built specimens, while few were observed in the transversely built specimens. The SLM Co-Cr specimens treated with IRH achieved comparable warping deformation and mechanical properties with those of the GFH-treated specimens. The IRH technology holds great potential for application to dental restorations.

Recent trends in hydronic radiant system technology for heating and cooling

Recent trends in hydronic radiant system technology for heating and cooling

A novel approach for enhanced hydrothermal synthesis of α-calcium sulfate hemihydrate crystals from phosphogypsum by microwave irradiation

Microwave radiation is a clean heating technology, which was utilized for efficient synthesis of high-value α-calcium sulfate hemihydrate (α-CSH) from phosphogypsum waste in salt solution.

DEVELOPMENT OF METHODS FOR CONTROLLING THE TECHNOLOGICAL PROCESS OF STRUCTURE FORMATION OF CONCRETE BASED ON CEMENT-DIATOMITE BINDERS BY ACOUSTIC EMISSION METHOD

The most important task of modern construction is to improve the efficiency, quality, environmental safety, reliability, and durability of structures and facilities, considering the reduction of material intensity and capital costs. Heat-insulating materials constitute a significant group of construction materials by volume and importance. The use of lightweight concrete in construction makes it possible to create enclosing structures that meet the modern requirements of housing comfort, architecture, urban planning, to reduce material intensity and costs of erecting buildings and their operation. Enclosing constructions from cellular concrete with high ecological characteristics are getting more and more application. The paper presents the results of research into the production of effective heat-insulating materials based on diatomites by forming cellular structures in the field of high frequency currents. The study also presents the substantiation of the principles of formulation and technological regulation of their properties. In the process of research, the technological modes of creation of cellular structures by sources of internal heat have been studied. The method of control and management of the processes of structure formation of porous materials obtained by the technology of internal heating in the fields of microwave currents has been developed. The studied control method allows using the average temperature mode of the system, not exceeding the optimum hydration temperature for microwave molding of cellular structures.

Study of Induction Heating of Metal Structures at Increased Frequency

Introduction. One of the conditions for trouble-free operation of moving and rubbing me­tal structures in winter is the absence of ice and snow accumulations in the operating areas of moving components. The same goes for moving agricultural constructions, which, for instance, can freeze to the surface outside the animal houses. In the article, based on the studying a turnout switch there is proposed the development of an innovative, more economical and cheaper method for heating moving parts. Aim of the Study. The study is aimed at creating a technology for heating sliding metal surfaces and at justifying parameters, developing and simplifying equipment design.Materials and Methods. Using a system approach, mathematical analysis and energy ba­lance methods, there were considered the main patterns of thermal processes in the contact zone of sliding metal structures. When considering these processes, there were made some assumptions. Namely, there were not taken into account soil thermal conductivity, air speed, and other physical processes, because they do not have a significant impact on the final results. These assumptions greatly simplify thermal calculations and obtaining the necessary analytical expressions to determine the parameters of induction heating elements.Results. The induction heating method for moving and rubbing metal structures in winter period has been proposed and tested, the main regularities have been revealed and technical characteristics have been determined. High efficiency and convenience of induction heating in comparison with other methods of electric heating have been proved. There have been obtained numerical values of parameters of induction heating elements, which agree with experimental data.Discussion and Conclusion. Based on the developed induction heating scheme, an experimental model with a power of up to 1 000 watts with a frequency of 10 kHz was made. The manufactured experimental model was studied in laboratory and production conditions. The estimated heating power of the part was 334 watts, the measured power was 351 watts. At the same time, the part weighing 20 kg heated up to 60 °C in 40 minutes. During production tests, the part was heated by 50 °C in 40 minutes.The research results can be used to design induction heaters operating at an increased frequency.

The Influence of Induction Hardening, Nitriding and Boronising on the Mechanical Properties of Conventional and Sintered Steels

Heat treatment technology changes all the mechanical properties of metallic materials. The influence of induction hardening, nitriding and boronising on the change in the microhardness, impact toughness, microstructure and coefficient of friction of conventional steels 42CrMo4 and 32CrMo12 has been examined and compared with results obtained in the sintered steels with an increased content of Cu, which were prepared using powder metallurgy technology. Widely used treatments for the examined materials include induction hardening and gas nitriding. This study focuses on comparing those technologies with alternative technologies of boronising. It was found that for powder metallurgy materials, boronising is a much more suitable process than nitriding because after the application of nitriding, the impact toughness dropped to one third of the impact toughness of the base material, while after boronising, the impact toughness remained unchanged. Through boronising, it was possible to achieve the unique possibility of improving the mechanical properties of sintered PM Fe-Cu-C steels and fully replacing the currently used nitriding process. Furthermore, compared to nitriding, it also increases the hardness of the surface layer many times to improve the friction properties and significantly increases the impact toughness.

Kinetics Dominated, Interface Targeted Rapid Heating for Battery Material Rejuvenation

AbstractThe ambitious pursuit of carbon neutrality underscores the pressing demand for closed‐loop recycling of lithium‐ion batteries (LIBs), amid escalating production and disposal challenges. Direct battery material recycling, emphasizing the rejuvenation of degraded materials, stands out as an environmentally benign alternative to conventional pyro‐ and hydro‐metallurgical processes that are intrinsically destructive. In addition, given the surface, interface, and interphase as the major failure mechanisms in degraded materials, rapid heating technology (RHT) emerges as a promising direct recycling method, harnessing its distinctive kinetics and thermodynamics to trigger highly time‐ and energy‐efficient, precisely defect‐ and interface‐targeted approach to revitalize degraded materials. This review summarizes recent advancements in RHT‐based LIB recycling strategies, focusing on active materials recovery, efficient regeneration, and reutilization, with emphasis on expedited kinetics and locally confined chemical reactions at interfaces. It also outlines the perspectives and future directions by emphasizing the need for re‐manufactured materials to meet increasing application demands. This comprehensive review aims to guide the recycling and upcycling of spent LIBs toward a green and sustainable battery economy.

Six years of high-resolution monitoring data of 40 borehole heat exchangers

Ground-source heat pumps (GSHPs) coupled with borehole heat exchangers (BHEs) are energy-efficient technologies for heating and cooling buildings. However, these systems often fail to operate at their full potential due to discrepancies between the assumptions made during the design phase and the actual conditions during operation. To enhance overall GSHP performance, it is crucial to collect and analyze long-term monitoring data from operating BHE fields. To our knowledge, no long-term, high-resolution dataset of double U-tube BHEs is currently publicly available. Additionally, most studies typically monitor only the inlet and outlet of the entire ground heat exchanger rather than individual BHEs, hindering detailed performance analysis. With this data descriptor, we present a 6-year dataset from a BHE field comprising 40 BHEs, each with sensors for volume flow and inlet/outlet temperatures, recorded every 30 seconds. We believe this dataset will enhance understanding of individual BHE performance, provide validation for BHE models, and thus support better GSHP design and operation.