Induction Heating Technology Research Articles

Analysis of heating performance of transverse magnetic inductor at different operating frequencies

Abstract Traditional induction heating technology has problems such as uneven temperature distribution and the need to improve heating efficiency and accuracy. Horizontal magnetic flux induction heating technology is a new type of induction heating technology with the advantages of energy efficiency, environmental friendliness, and suitability for local workpiece heating. It is widely used in metallurgy, mechanical manufacturing, light chemical industry, and other fields, holding important economic value. This article studies the heating performance of transverse magnetic inductors at different operating frequencies, simplifies the heating process calculation using finite element analysis, selects stainless steel 405 as the heating material, and sets commonly used parameters such as conductivity and magnetic permeability as fixed values, with frequency as the control variable. Using SolidWorks software to establish a model and COMSOL Multiphysics for simulation, simulated three frequencies: 500Hz, 1kHz, and 5kHz. Analyzed the section temperature, current density distribution, and heating efficiency.

Investigating the Effects of Induction Heating on a Submerged Hollow Cylindrical Element

ABSTRACTThis article proposes an induction heating element that addresses heat transfer and thermal homogenization while being fully submerged in a liquid, specifically focusing on heating of water as a case study. The design calculations, fabrication, and realization of a resonant induction heating system that heats the proposed heating element are presented. The geometric shape of proposed heating element is a hollow cylinder that maintains structural strength while delivering required thermal energy because of an external time‐varying magnetic field. Detailed mathematical modeling of the proposed heating element's equivalent electric circuit has been presented while considering physical parameters including diameter, thickness, height, material properties, magnetic field frequency, and skin effect. A laboratory scale prototype of the induction heating system including the proposed heating element has been built, and experiments have been demonstrated. The experimental results of the working induction heating resonant inverter and RLC resonant circuit inductance and capacitance with induction load are presented. Additionally, the results of thermographic images and temperature–time profile of the water sample, which was heated using the proposed heating element, are provided to demonstrate the heating element's reliability and practicality. This research contributes to the field of induction heating technology by investigating a heating element that is submerged in a liquid medium, resulting in a uniform temperature distribution throughout the liquid. The conventional method of heating water in a stainless steel cup‐shaped container is an inefficient heat transfer process. In stainless steel cup‐shaped containers, a portion of the energy input used to boil the water is lost to the environment through the surface area of the container that is not in direct contact with the water. This heat loss occurs due to the container's design, which exposes a large surface area to the surrounding environment, allowing thermal energy to dissipate through conduction, convection, and radiation.

Joining SiC ceramics with CaO-Al2O3-SiO2 mixed powder/glass based on induction heating

CaO-Al2O3-SiO2 mixed powder and glass were used as the joining materials to join SiC ceramics by induction heating in a joining temperature range of 1400–1600 °C under pressureless condition with heating and cooling rates of 100 °C/min. The joint prepared with CaO-Al2O3-SiO2 mixed oxide powder as joining material has the highest shear strength of 60.09 ± 6.22 MPa at joining temperature of 1500 °C, which contains triclinic CaAl2Si2O8 crystalline phase generated by chemical reaction in the holding process. In contrast, the joint produced with CaO-Al2O3-SiO2 glass powder at 1500 °C also has the highest shear strength of 75.76 ± 2.34 MPa, which contains hexagonal CaAl2Si2O8 and quartz generated through crystallization in the holding process due to rapid cooling rate of induction heating. In this study, the feature of mixed powder and glass joining by the induction heating technology was discussed to provide an effective and economic method for ceramic joining.

Phase transition heat storage and self-healing mechanism of spinel-calcium aluminate composite aggregate in corundum castable

Corundum-spinel castable is a vital refractory material used in steel ladle linings. Conventional approaches for assessing the thermal shock resistance of corundum-spinel refractory are not entirely representative of the actual application scenarios. This study investigates the influence of spinel-calcium aluminate composite aggregate on the thermal shock resistance of corundum castable using supersonic frequency induction heating technology. The research uncovers how CMA aggregate enhances the thermal shock resistance of corundum castable by cyclic thermal shock tests under varying operational conditions. Results reveal that the incorporation of CMA aggregate led to significant improvements in cold crushing strength and strength retention ratio following thermal shocks. The observed enhancement predominantly stems from the presence of CA/CA2 phase within the CMA aggregate, which undergoes a solid-liquid phase transition at high temperatures, enabling the absorption and retention of substantial heat and aiding in the repair of microcracks within the materials and at the interfacial regions.

Numerical study on induction heating enhanced methanol steam reforming for hydrogen production

Electromagnetic induction heating technology, characterized by its non-contact thermal heat transfer, diminished thermal inertia, and facile temperature management, is applied in this study to enhance catalytic methanol steam reforming (MSR) reaction process. A two-dimensional reactor model was developed integrating electromagnetic field coupling with MSR reactions, fluid dynamics and heat transfer. In the reactor, heat is induced instantaneously on the magnetic material through an electromagnetic induction process, which generated by renewable electricity. Results showed that the Internal - Double Row Cylinder (IN-DRC, cylinder means that the shape of induction heating element is cylindrical.) highest heating efficiency is 38.3%, which is limited by the kinetics of MSR reaction. Here, thermal efficiency reaches its maximum with the reaction channel outlet temperature reaching about 580 K. Internal - Double Row Cylinder (IN-DRC) and Internal - Double Row Ball (IN-DRB, ball means that the shape of induction heating element is spherical) methanol conversions are virtually identical, with a maximum value close to 100%. Furthermore, the findings that the adoption of internal induced heating, in contrast to external heating, across the four reactor designs can effectively mitigate temperature gradient within the reactors. This reduction in thermal disparity significantly amplifies methanol conversion within the reactor, thereby markedly enhancing its overall performance in hydrogen production.Therefore, non-contact internal induction heating method has the potential for substantially hydrogen production processes.

Research on erosion wear behavior of NiTi alloy coating fabricated via high-frequency induction heating technology

NiTi alloy is widely used in extreme working conditions due to its pseudoelasticity, shape memory effect and wear resistance. In this study, the NiTi alloy coating (Ni49.8Ti50.2 (at%)) was fabricated by high-frequency induction heating. The coating was well-formed on the surface of cemented carbide YG8 and converted to crystalline after aging treatment. The results of 70h erosion wear experiments carried on the rotary erosion wear test device showing that the erosion wear amount of the coating was reduced by 93 % compared with that of YG8, resulting from the deformation recovery effect. Moreover, the main erosion wear mechanism of the coating was micro-cutting and ploughing. This study can provide technical support and theoretical basis for preparing of NiTi alloy coating and erosion wear resistance.

Modeling and Design of Induction Heating Systems

This thesis is based on a specific industrial application of induction heating technology: induction hardening. The main objective is to create a simulation model that predicts the whole heating process, combining the electrical simulation with the electromagnetic-thermal analysis, employing electrical simulation software and finite element tools, respectively. This proposed model will be called as dynamic model in the following lines.

Study on temperature field in the process of induction heat treatment with current assisted weld double side method

At present, in the process of weld induction heat treatment, the common method is to carry out centralized induction heating in the weld area, which will lead to large radial temperature difference of the weld, poor controllability of temperature distribution and easy to cause the defects of residual stress concentration in the weld area. To solve the above problems, this paper adopts the two-sided method to conduct induction heating on both sides of the weld, and at the same time, the auxiliary pulse current is passed into the weld to improve the quality of the weld. ANSYS finite element software is used to establish a multi-field coupling prediction model of electric-magnetic-thermal structure, and explore the distribution law of the auxiliary pulse current and the temperature field of the weld. Finally, an experimental study of pulsed current assisted two-sided induction heating is carried out. Temperature test and metallographic test were carried out respectively to verify the effectiveness of pulsed current assisted induction heating technology.

Application of novel microwave-assisted induction heating technology for extending the shelf life of ready-to-eat rice through microbial, physical, and chemical quality preservation

Microwave-assisted induction heating (MAIH) is a composite heating system that combines top-down microwave irradiation (1000 W, 2450 MHz) with bottom-up electromagnetic induction (1500 W). Rice samples prepared by both MAIH methods (120 °C for 240 s and 100 °C for 300 s) and traditional steam cooking (100 °C for 30 min) were analyzed for microbial count, color, pH value, and hardness during storage at 35 °C, 25 °C, and 4 °C. The results revealed that MAIH-treated rice demonstrated no detectable microbial growth at any storage temperature, whereas steamed rice exhibited microbial growth with increasing aerobic plate counts at 35 °C, 25 °C, and 4 °C after two, four, and sixteen weeks, respectively. Color analysis revealed a decline in L* and W values, with increased b* values over time for all samples at all storage temperatures. The pH values of the MAIH-treated rice remained stable, while steamed rice demonstrated a pH decrease during later stages of storage at 25 °C and 35 °C. The hardness of MAIH-treated rice slowly increased at 25 °C and 35 °C, whereas the steamed rice experienced a notable decrease. At 4 °C, all samples demonstrated increased hardness, with steamed rice having significantly higher values than MAIH-treated rice. Overall, MAIH treatment effectively delayed color, pH, and hardness alterations in rice in comparison to traditional steam cooking during storage. Industrial relevanceThe MAIH equipment is a novel thermal processing technology and provides the efficient pasteurization, reduced processing time, and improved overall quality of ready-to-eat (RTE) rice. Therefore, the MAIH technology is a viable future alternative for thermal processing method that possesses huge potential in the development of RTE rice products.

An Intelligent Optimized Control System for Induction Heating Application

In the modern era, induction heating (IH) technology is utilized for industrial functions like medical applications and domestic applications. Furthermore, efficient uses such as control topologies, magnetic component design, and power electronics have high demand as well as cost-effective with respect to advanced technology. However, IH technology directly targets the power converter and coil so it has wasted higher amount of heat. Also, high power dissipation in an IH system leads to high energy costs and reduced system performance. Hence, various approaches are developed to minimize power dissipation. However, they cannot reduce power dissipation in the induction coil. Thus, a novel Decision-based Squirrel Control System was developed in this article to decrease the power wastage in induction coil optimally. The developed model’s squirrel fitness function monitors power wastage and compensates them by tuning it. The developed model is executed in MATLAB/Simulink, and the results are determined. In terms of rising time, settling time, overshoot, and error rate. Here, the proposed work can achieve 0.075s resting time, 1.02s settling time, 0.05s overshoot, and 0.29% of error rate. The comparative assessment proves that the presented approach attained better results than others.

Continuous decontamination of cumin seed by non-contact induction heating technology: Assessment of microbial load and quality changes

Over the past few decades, the demand for high-quality food has increased steadily. Therefore, it is essential to develop innovative technologies that effectively reduce microbial load while minimizing any negative effect on the quality of spices. The objective of this study was to determine the efficacy of a self-designed non-contact induction heating system using contaminated cumin seeds. The non-contact induction heating decontamination process was performed at different temperatures of 115, 135 and 155°C and durations (45, 60 and 75 s) through continuous process (screw conveyor) in Pyrex cylinder chamber. Various parameters including microbial load, color characteristics, essential oil content, surface morphology, sample temperature, and energy consumption were analyzed as dependent variables in the study. The results showed that the treatment combination (155°C - 60 s) reduced the aerobic plate count from 6.21 to 2.97 CFU/g. Mold, yeast and coliforms in the treatment combination (155°C-45 s) were also reduced by 3.26 and 3.6 CFU/g, respectively. The total color difference of the samples increased due to the degradation and alteration of pigments at high temperatures. However, no statistically significant disparity in essential oil content was observed between the treatment groups and the control group. The quantities of essential oil components in the cumin seeds were determined to align with the ISO standard, with the primary constituents identified as follows: Terpinen-7-al γ (38.98%), Cumin aldehyde (20.75%), γ-Terpinene (18.81%), β-Pinene (13.66%), and p-Cymene (6.2%). In summary, non-contact induction heating system shows promise as an effective technology for surface decontamination of spices. The acquired findings contribute to a deeper understanding of the impact of the induction heating process on both the microbial contamination levels and the quality attributes of cumin seeds. This scientific knowledge serves as a foundational framework for the prospective adoption and integration of this technology on a larger industrial scale.

A novel mechanical attachment for biaxial tensile test: Application to formability evaluation for DP590 at different temperatures

A novel mechanical attachment for conducting in-plane biaxial tensile test is provided in this paper. In this attachment, the conversion of force from an external actuator into two pairs of orthogonal forces is achieved by specially designed trapezoidal blocks. By using trapezoidal blocks with different inclination angles, biaxial tensile tests of six different tensile ratios can be performed. A heating device is designed for the attachment to conduct thermal biaxial tensile tests. The heating device adopts a combination of the induction heating technology and the conduction heating method. With the developed mechanical attachment and the heating device, the forming limit curves (FLC) of DP590 sheets at ambient temperature, 300 °C, 400 °C and 500 °C are determined using biaxial tensile tests. A classical Nakazima test procedure at ambient temperature is carried out to establish a reference FLC for the material, and the reference FLC is further used to evaluate the results from biaxial tensile tests. Furthermore, an anisotropic GTN model based on Yld2000-3d yield criterion is calibrated by inverse identification procedures and applied to predict the localized necking and fracture for DP590 sheets under biaxial tensions.

Iron-encapsulated carbon nanotubes catalyze degradation of organic pollutants enabled by magnetic induction heating

Organic pollutants have become an urgent problem for human health and the ecological system. The development of a multifunctional and efficient catalyst is of great significance for environmental governance. However, the catalytic conversion process of organic pollutants requires a large amount of energy, and traditional energy supply may further exacerbate environmental pollution. Herein, we propose an integrated magnetic material system that can serve as a magnetic heating medium to provide energy and as catalyst to promote the catalytic reaction. Iron-encapsulated carbon nanotubes activate peroxomonosulfate to generate active free radicals, achieving nearly complete degradation of the organic pollutant Orange II. The reaction exhibits excellent stability and repeatability, which may be attributed to the heating method applied to the magnetic sites, allowing the iron-encapsulated carbon nanotubes to maintain a stable structure. Further loading with Ag allows the catalyst to achieve near 100 % conversion of formaldehyde in air. This study aims to provide an effective and green strategy for environmental pollution treatment by integrating magnetic induction heating and catalytic conversion technology.

Research on the Improvement of Lithium-Ion Battery Performance at Low Temperatures Based on Electromagnetic Induction Heating Technology

As the major power source for electric vehicles (EVs), lithium-ion batteries (LiBs) suffer from the degradation of technical performance and safety at low temperatures, which restricts the popularization of EVs in frigid regions. Thus, this study developed an extremely fast electromagnetic induction heating system in order to improve the poor performance of LiBs in cold weather. An electrochemical–thermal coupling model (ETCM), validated against the experimental results of charge and discharge, which successfully predicted LiB voltage, temperature, and other physical characteristics at various ambient temperatures, was established in COMSOL Multiphysics 6.0 as a development tool for evaluating the heating effect of the system. When the copper coil is subjected to a SAC (sinusoidal alternating current) of 8 A and 50 Hz, the LiB can be heated from 243.15 to 293.15 K within 6 min with an instantaneous temperature increase rate of 0.263 K/s and a homogeneous temperature distribution. The results of the capacity calibration, cyclable lithium detection, and HPPC simulation show that the heating method can visibly increase the Li+ concentration inside the active particle, and there was only a tiny concentration gradient on the surface of the particle. In addition, the internal resistance was approximately a quarter of that without heating; therefore, both the discharge energy and specific power boost were two times higher than the original level. Compared to the normal charge–discharge cycles at 293.15 K, the capacity retention of the LiB only decreased by 0.23% after 60 consecutive heating cycles, so the heating method can balance the temperature rise, work capacity, and LiB health. Furthermore, the improvements in the thermal insulation condition and material thermal conductivity are two feasible ways to optimize the temperature-increase effect.

A Simplified Design Method for Quasi-Resonant Inverter Used in Induction Hob

Induction heating (IH) technology is widely recognized and utilized in residential applications due to its high efficiency and safe operating characteristics. Resonant inverter circuits are widely used in IH systems because of their high efficiency and ability to perform soft switching. Among the various resonant inverters used in IH systems, the single-switch quasi-resonant (SSQR) inverter topology is typically preferred for low-cost and low-output-power applications. Despite its cost advantage, the SSQR topology has a relatively narrow soft-switching range, which can be unstable depending on the electrical parameters of the load and the resonant converter circuit. Accurately determining the capacitance value of the resonant capacitor and the inductance value of the induction coil, which are the key circuit elements of the SSQR induction cooker, is crucial for designing a reliable, efficient, and durable cooking system. In other words, there exists a critical relationship between the resonant converter circuit parameters, load characteristics, and safe operating conditions. Additionally, when considering closed-loop control methods used for power control and safety, selecting appropriate resonant circuit elements becomes vital in ensuring both reliable and efficient operation. This paper focuses on a novel and simplified design method for the SSQR inverter utilized in household appliances. The proposed method and its advantages in terms of the safe operating area of the switch are theoretically investigated and verified through simulations and prototype circuits.

Physicochemical Quality Retention during Cold Storage of Prepackaged Barramundi Meat Processed with a New Microwave-Assisted Induction Heating Technology.

Microwave-assisted induction heating (MAIH) is a composite microwave and induction heating to supply rapid and uniform heating of food. A recent study showed that the optimum MAIH heating condition for barramundi meat was 90 °C/110 s or 70 °C/130 s. This study examines whether the microwave-assisted induction heating (MAIH) technology (at 70 °C for 130 s or 90 °C for 110 s) can more effectively slow down the quality loss of barramundi meat during cold storage than the traditional boiling method (at 90 °C for 150 s). The results show that no microbial growth was observed in the three groups of heated barramundi meat samples during the 60 days of cold storage. However, the MAIH technology slowed down the increase in the total volatile basic nitrogen (TVBN) content more significantly than the boiling method. As the cold storage time increased, though, the L* (lightness), a* (redness), and W (whiteness) values decreased, while the b* (yellowness) and color difference (ΔE) values increased in the three treatment groups. However, the MAIH technology slowed down the decrease in the L*, a*, and W values more significantly, and produced a ΔE value smaller than the boiling method. Moreover, the MAIH technology ensured higher hardness and chewiness of the barramundi meat than the boiling method. Overall, the MAIH technology slowed down the quality loss of the barramundi meat and maintained better color and texture during cold storage.

A Reduced Switch Count High-Frequency Single-Phase 5-L MLI for IH Applications

Nowadays, multilevel inverter (MLI)-based induction heating (IH) technology is the best-suited option in many domestic, commercial and medicinal applications because of its higher efficiency, low cost, fast heating and lower electromagnetic interference (EMI). This paper presents reduced components count high-frequency (HF) single phase five-level (5-L) MLI for IH applications. The working methodology of the proposed system has been analyzed in the multicarrier phase disposition pulse width modulation (MC-PD-PWM) method in high switching frequency i.e., 10[Formula: see text]kHz. In addition, the proposed topology can produce output voltage twice of input voltage without any external source. Moreover, the detailed power loss and reliability analysis have been evaluated for the proposed system. In terms of switch count and efficiency, the single-phase 5-L inverter architecture is compared to some conventional and current topologies. Finally, to validate and justify the operation of the proposed system, the simulation and experimental results of five-level inverter are presented.

Research on the heating rate of induction heating CFRP and temperature field based on image entropy

The electromagnetic induction heating technology has the advantages of fast heating speed and cleanness, and can realize the rapid temperature curing of carbon fiber reinforced polymer (CFRP). In order to improve production efficiency and curing quality, a finite element model of induction heating CFRP was established, and the temperature field distribution and heating mechanism during induction heating of CFRP were analyzed. The correctness of the model and conclusion is verified by experiments. On this basis, the influence of current, diameter, frequency and distance on the heating rate is analyzed, and it is found that frequency has the greatest influence on the heating rate. In addition, the mathematical relationship between temperature field uniformity and entropy value is established, which provides a quantitative analysis method for the temperature field uniformity of induction heating CFRP. Through optimization analysis, it is obtained that for the CFRP mentioned in the article, the coil size is selected between 65 mm and 95 mm, and the spacing is between 3.5 mm and 6.5 mm, so that the temperature field has the best uniformity.

Dual-Output Extended-Power-Range Quasi-Resonant Inverter for Induction Heating Appliances

Induction heating technology provides efficient and reliable heating processes that outperform other classical heating methods based on fossil fuels or resistive heating. Among its many industrial, domestic, and biomedical applications, domestic induction heating appliances are a popular choice due to these advantages. This technology requires high-performance and cost-effective inverters that take most of the power devices and the converter topology. Depending upon the desired performance and output-power range, different power converters are employed. However, currently, most platforms rely on the well-known series resonant half-bridge topology. Single-switch topologies offer a cost-effective implementation but are limited to the low-cost low-performance markets due to their limitations in terms of output power and power control. In this context, this paper proposes a high-performance dual-output quasi-resonant inverter for modern induction heating appliances. Unlike state-of-the-art proposals, this converter achieves a full-output-power operating range of up to 3.6 kW. Consequently, it provides a high-performance cost-effective alternative to current implementations. The proposed converter is analyzed in this paper and experimentally verified using a dual-output 3.6-kW induction heating appliance prototype.

Possibility of processing tungsten dust waste from the nuclear fusion process by a combination of several technologies

The processing of tungsten dust waste from the nuclear fusion process is being considered for the EU DEMO within the Workpackage Safety and Environment in the EUROfusion programme.A multi-step procedure with a combination of several independent technologies is proposed. Specific technologies are gradually being proposed, however their combination has not been tested yet. Removal of tritium from tungsten dust by a Molten Salt Oxidation technology (MSO) is investigated while, simultaneously, tungsten is retained in the molten salt and tritium is trapped in the form of condensed tritium water. Tungsten salts are concentrated in several stages by a combination of chemical methods, settling, and centrifugation. The dissolution and concentration procedures alternate in a defined manner. The concentrate is gradually enriched with tungsten and tungsten salts. The molar volume of tungsten progressively increases in the concentrated salt suspension.Further removal of certain impurities, decomposition of salts, and the increase of the tungsten concentration in the product can be achieved by means of Induction Melting or Induction Heating in a Cold Crucible (IMCC or IHCC) in a suitable atmosphere. The final stage is the reprocessing of the concentrated tungsten product from the dust form into a compact piece of material. Induction Heating technology will enable its sintering, compaction, and reduction of porosity.