Electromagnetic Heating Research Articles

Enhancing the catalytic H2 production performance of magnetic Ni-Fe2O3-C catalyst in biomass steam gasification using electromagnetic induction heating

In this study, a novel magnetic Ni-Fe2O3-C catalyst combined with electromagnetic induction heating in biomass steam gasification was proposed to enhance H2 production. Better catalytic performance for H2 production was observed with the Ni-Fe2O3-C catalyst under induction heating, resulting in an increase in H2 yield from 735.1 to 2271.2 mL/g-biomass (a 209.1 % enhancement). SEM, TGA and XRD analysis demonstrated a significant decrease in coking deposition, caking, and particle agglomeration of the Ni-Fe2O3-C catalyst under induction heating, while maintaining more active sites. Importantly, the benefits of induction heating were also applicable to different magnetic catalysts like Ni-Al2O3-C, Ni-ZrO2-C, and Ni-MgO-C. Experimental results revealed a logarithmic correlation between the increase in H2 yields due to induction heating and the magnetic saturation (Ms) of the catalysts. The Ni-Fe2O3-C catalyst, with a high Ms of 50.9 emu/g, showed the highest catalytic activity for H2 production under induction heating in this study.

Direct and Sensitive Detection of Mercury in Soil by Portable Electromagnetic Heating Vaporization and Purge-and-trap Followed by Microplasma Optical Emission Spectrometry

Direct and Sensitive Detection of Mercury in Soil by Portable Electromagnetic Heating Vaporization and Purge-and-trap Followed by Microplasma Optical Emission Spectrometry

An analysis of temperature control for electromagnetic induction heating of CFRP based on sparrow search algorithm

Accurate temperature control during the induction heating process of carbon fiber reinforced polymer (CFRP) is crucial for the curing effect of the material. This paper first builds a finite element model of induction heating, which combines the actual fiber structure and resin matrix, and systematically analyzes the heating mechanism and temperature field distribution of CFRP during the heating process. Based on the temperature distribution and variation observed in the material heating process, a PID control method optimized by sparrow search algorithm is proposed, which effectively reduces the temperature overshoot and improves the response speed. The experiment verifies the effectiveness of the algorithm in controlling the temperature of CFRP plate during the induction heating process. This study provides an effective control strategy and research method to improve the accuracy of temperature control in the induction heating process of CFRP, which helps to improve the results in this field.

Electromagnetic–thermal–mass transport triple hybrid model for energy-efficient hydrogen release from metal particles by induction heating

Hydrogen storage in metals is anticipated to be a highly promising technical approach for managing hydrogen in diverse energy applications, emphasizing the need to establish efficient operating conditions. In this study, we developed a numerical model that can simultaneously calculate hydrogen and heat transport combined with electromagnetic induction heating of metal particles. Using the developed numerical simulator, we investigated the behavior of the hydrogen release process from the hydrogen-absorbing metal and proposed important indicators for the operation. The fractions of the electromagnetic energy absorbed by the metal particle used for the hydrogen release, sensible heat, interfacial heat conduction, and thermal radiation were systematically evaluated. Considering the trade-off between temperature rise and the hydrogen concentration gradient, an optimal diameter of metal particles existed for the maximum hydrogen release rate. Similarly, the trade-off between temperature rise and energy consumption revealed an optimal electromagnetic power density for the heat utilization fraction for hydrogen release. Our electromagnetic–thermal–mass transport triple hybrid model constitutes a useful numerical simulator for the design of energy-efficient hydrogen storage systems.

Enhancement of laser ablation via high-frequency electromagnetic induction heating

The efficiency of pulsed laser ablation has always been the focus point of research. A novel high-frequency electromagnetic induction heating-assisted laser ablation scheme is proposed and investigated to enhance the efficiency and improve the surface processing quality during the nanosecond laser ablation of metal substrates. To reduce laser energy required to reach the ablation threshold of metal, this method utilizes the electromagnetic induction to rapidly elevate substrate temperature, making the metal easier to be ablated. The results show that ablation width increases 16% and ablation depth increases 31% with the assistance of electromagnetic induction heating at a laser fluence of 1.32 J/cm2, which increases 90% of the laser-ablated volume. Meanwhile, the surface ablation quality is significantly improved due to the smaller temperature gradient around the ablation region. This new method has great potentials in the laser micromachining at a higher processing efficiency and better laser-processed surface quality.

Who will ‘go electric’? American homeowners' perceptions of home energy sources and home electrification

In the context of the global climate crisis, the role the building sector plays in direct consumption of fossil fuels, especially natural gas, has come under increased scrutiny. Several major cities have initiated a phase out of natural gas hookups in homes and other buildings, requiring use of electric appliances. Additionally, with the passage of the 2022 Inflation Reduction Act, major incentives came available to help homeowners purchase and install electric appliances in their residences. Currently, over half of American homes use natural gas for heating or cooking, but research is needed to understand public opinion of household electrification. Here, we use 2021 survey data of American homeowners with electricity in the household (n = 4470) to analyze distribution of different energy sources currently used by homeowners, favorability toward gas versus electric appliances, and attitudes toward home electrification. We find that homeowners in the South, Midwest, and Intermountain West regions of the US are more likely than those in the New England area to already reside in electric-only homes, but we don't find the same geographic variation in support for home electrification. We also find that homeowners who are politically liberal, don't already use natural gas, have children at home, live in more urban areas, use rooftop solar, already use an induction stove or heat pump, and believe electricity is safer than natural gas are more supportive of electrification. These findings provide clues as to who is more and less likely to adopt electric household technologies.

Difference comparison of characteristic aroma compounds between braised pork cooked by traditional open-fire and induction cooker and the potential formation cause under electromagnetic cooking

The characteristic aroma compounds of braised pork were identified through molecular sensory science and PLSR analysis, and the difference between two cooking methods, traditional open-fire (BPF) and induction cooker (BPC), was compared. Seventeen aroma compounds with odor activity values (OAVs) > 1 were identified in both samples. BPF revealed higher OAVs for most of the aroma compounds compared to BPC, and the higher aroma quality. Aroma recombination and omission experiments confirmed that twelve aroma compounds significantly contributed to the characteristic aroma of braised pork, and eight compounds such as hexanal, (E)-2-octenal, and methanethiol were further confirmed as important contributors by PLSR analysis. Furthermore, PLSR analysis clarified the role of aldehydes such as hexanal, (E)-2-octenal, and (E,E)-2,4-decadienal in contributing to fatty attribute, whereas methanethiol was responsible for the meaty aroma. These characteristic aroma compounds mainly derived from lean meat due to its high content of phospholipids, and the exogenous seasonings contributed to the balanced characteristic aroma profile of braised pork by altering the distribution of these characteristic aroma compounds. Variations in heating parameters affected the formation of lipid oxidation and Strecker degradation products, which might explain aroma discrepancy between braised pork cooked by two methods with different heat transfer efficiencies.

Effect of aging level on the healing properties of an induction-heated ultra-thin wearing course and its mechanism

Electromagnetic induction heating can accelerate crack self-healing in asphalt concrete and extend its service life. In the maintenance project of existing pavements, induction heating and ultra-thin wearing course can be combined by paving functional induction heating wearing course. However, the ultra-thin wearing course is directly affected by the environment and loading, and undergoes aging in the service process. Thermo-oxidative aging is an irreversible and important mechanism that seriously affect the rheological and healing properties of asphalt. Therefore, the purpose of this work is to examine the impact of thermo-oxidative aging on the induction heating-healing of an ultra-thin wearing course mixture. Firstly, the AC-5 induction heated ultra-thin wearing course (IHUC) containing 1 % steel wool fiber by aggregate mass was prepared. Subsequently, the IHUC was aged to six different levels. Then, the induction heating and healing properties of the aged IHUC were evaluated. Simultaneously, the aged asphalt binder was extracted and its rheological characteristics and chemical alterations were studied. The outcomes showed that the heating rate of IHUC decreased, but the temperature gradient effect reduced at higher aging level. The optimal healing temperature of IHUC shifted to a higher temperature region and the healing rate decreased. Both heating cycles and thermo-oxidative aging reduce healing effectiveness, but the impact of heating cycles is less compared to aging. Rheology and chemical structure test results of extracted asphalt binder showed that the transformation of the molecular structure caused the fluidity and self-healing properties of asphalt were decreased. This ultimately decreased the healing rate of IHUC.

Short-voltage pulse generation for induction heating load detection on a multi-output inverter with shared power devices

Purpose The purpose of this paper is to develop a load detection method for domestic induction cooktops. The solution aims to minimize its impact in the converter power transmission while enabling the estimation of the equivalent electrical parameters of the load. This method is suitable for a multi-output resonant inverter topology with shared power devices. Design/methodology/approach The considered multi-output converter presents power devices that are shared between several loads. Thus, applying load detection methods in the literature requires a halt in the power transfer to ensuring safe operation. The proposed method uses a complementary short-voltage pulse to excite the induction heating (IH) coil without stopping the power transfer to the remaining IH loads. With the current through the coil and the analytical equations, the equivalent inductance and resistance of the load is estimated. The precision of the method has been evaluated by simulation, and experimental results are provided. Findings The measurement of the current through the induction coil as a response to a short-time single-pulse voltage variation provides enough information to estimate the load equivalent parameters, allowing to differentiate between no-load, non-suitable IH load and suitable IH load situations. Originality/value The proposed method provides a solution for load detection without requiring additional circuitry. It aims for low power transmission to the load and ensures zero-voltage switching and reduced peak current even in no-load cases. Moreover, the proposed solution is extensible to less complex converters, as the half bridge.

Design of CuS composite carbon-based Ni Al-LDH multifunctional phase change composite with electromagnetic shielding performance and heat storage capacity

CuS-based composites are widely used in the fields related to photothermal energy storage and electromagnetic shielding and are excellent candidates for composites with phase change materials. To meet the requirements of micro-integration and electromagnetic resistance of electronic products and optimize the thermal management of electronic products, it is necessary to prepare new flexible composite phase change materials. In this paper, through the design of MPC@Ni Al-LDH/CuS double-layer structure, two-step vacuum filtration method is used, and the highly conductive materials CuS and MPC are introduced into the manufacture of PCM films. With the help of Ni Al-LDH, flame retardancy is introduced. The electromagnetic wave absorption performance is enhanced, and the existence of nano-cellulose (CNF) makes the film have excellent mechanical properties. Ni Al-LDH/MPC and CuS substrates with stable and high mechanical properties are prepared by ultrasonic treatment. According to scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform-infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), differential scanning calorimetry (DSC) and thermogravimetry (TG) characterizations, PEG successfully entered the MPC/CuS skeleton by vacuum filtration, and flexible phase change composite bilayers (MLPC) were obtained. Due to the synergistic effect of structure and components, the obtained composite film has many different excellent functions. Specifically, when MPC@Ni Al-LDH is 15 wt%, the phase transition enthalpy, thermal conductivity, electromagnetic shielding, and electrical conductivity are 146.8 J/g, 1.07 W/m·K, 38.8 dB and 126.4 S/m, respectively. The 3600 s infrared temperature measurement results show that the sample has stable thermal properties. Due to the presence of CuS, when MPC@Ni Al-LDH is 5 wt%, its absorbance can be kept at 1.51 L/(g·cm), and its photothermal conversion efficiency can reach 90.6 %. The MPC/CuS structure in the composite film provides many heat transfer channels, which reduces the phonon scattering in the heat transfer process and significantly increases thermal conductivity. Therefore, this multifunctional flexible phase change film can be used in photothermal conversion devices and for thermal management of electronic equipment, and it has broad application prospects in wearable equipment design due to its excellent electromagnetic shielding ability and infrared thermal stealth ability.

Development of Fly Ash and Light Weight Mineral Granules Based Thermal Insulated Ceramic Container Bases for Keeping Hot Pot & Hot Bowl

Thermal insulation based product development is the most important concern in the present age because we are using so many types of heating and cooking and baking devices and electronic equipment like microwave ovens, induction cook tops, Oven toaster Grillers, Electric tandoor, Roti makers, domestic furnace and electronic coffee & tea makers. When we take out our bowls and pots from the microwave ovens and such type of other kitchen devices then heat present in the walls of the containers like utensil, bowl & pot and heat present in the cooked food damages the top of the table and table covers. In order to prevent such things there is a burning need of development of thermal insulation bases and mats.

Computational study of a helium-propellant microwave electrothermal thruster

The microwave electrothermal thruster (MET) utilizes wave-exited microdischarges to heat gas flows, enhancing the specific impulse of the thruster. Our computational study investigates a 17.5 GHz helium-propellant MET, employing a two-dimensional, axisymmetric fluid model of plasma coupled with electromagnetic wave and gas flows. The discharges operate in the glow regime, remaining weakly ionized, and in thermal non-equilibrium. The plasma densities reach approximately 1020m−3, and the gas temperature is around 2000 K. Even a slight off-resonant frequency operation results in a significantly lower plasma density and gas temperature. Gas heating, primarily driven by electromagnetic Joule heating, plays a critical role in influencing the overall discharge behavior. The measured peak thrust and specific impulse are 8.24 mN and 292 s, respectively, at a mass flow rate of 3.2 mg/s with 30 W of power. Compared to a cold gas thruster, there is a significant increase in the specific impulse by a factor of approximately 1.7. The enhanced performance trades off with propulsive efficiency, which decreases by a factor of 1.5 from the peak 65% at 10 W. This is due to higher energy losses to cavity walls from heat conduction with increased power. These findings underscore the critical balance between the input power and mass flow rate to improve the MET performance, highlighting the importance of power management to maximize thrust and efficiency. Furthermore, the predicted thrust and specific impulse agree well with experimental values for nominally similar MET thruster studies in the literature.

Increasing the underground coal gasification efficiency using preliminary electromagnetic coal mass heating

The purpose of this research is to explore the possibilities of using a high-frequency electromagnetic field for heating coal seams in the context of underground coal gasification. The research is based on mathematical models that take into account the physical parameters of the electromagnetic field. The methodology includes the calculation of thermal powers, exposure duration, temperature profiles and reaction rates. The research results indicate significant potential for using high-frequency electromagnetic field for coal seam pre-heating. Possibilities of using a high-frequency electromagnetic field for heating the mass in the context of underground coal gasification have been explored. The mathematical models developed and calculations performed broaden the understanding of heating processes in such systems. It has been determined that field parameters, such as frequency and power, influence the heating efficiency and temperature distribution. The obtained scientific results present new opportunities to increase the efficiency of underground coal gasification as an alternative energy source and will contribute to achieving a more efficient and sustainable future energy supply. The use of a high-frequency electromagnetic field can be useful when gasifying low-grade or low-thickness coal seams, when there is a need to intensify the gasification process.

Performance improvement of metal hydride hydrogen compressors using electromagnetic induction heating

While there are some hydrogen refueling stations (HRS) functioning in different parts of the world, their use is not widespread enough, primarily due to their expensive cost. Hydrogen compression is a main contributor to the capital and operation costs of the HRS. By improving H2 compression technology, it is possible to optimize the infrastructure for refueling with hydrogen in terms of cost and performance. The use of metal hydride hydrogen compressors (MHHCs), which have the potential to be inexpensive and have the ability to use waste heat and renewable energy sources for the H2 compression, is a promising solution to overcome this issue. The duration of the H2 compression cycle is nevertheless a serious challenge due to the metal hydride (MH) bed's low heat conductivity. As a heating technique to improve the performance of MHHCs, electromagnetic induction (EMI) is examined numerically for the first time in this work. The dynamic behavior of a two-stage MHHC with each MH reactor having an external heat exchanger and being ringed by a copper coil traversed by an alternating current is described by a two-dimensional mathematical model, which was established and successfully verified by the reference data. Numerical simulations were performed with the help of this model, and the findings showed that the EMI heating method is faster than the heat transfer fluid (HTF) heating technique. For instance, at a delivery temperature of 373 K and a supply pressure of 20 bar, it is possible to produce 106 NL H2 per kilogram of HPMH at a pressure of 97 bar with a 74 % shorter compression time than with the HTF heating technique.

Experimental study on preheating and salt circulation performance of a single receiver tube based on induction heating

The design of a light source for a molten salt receiver experimental system has become challenging owing to the complex heating characteristics of the half-circumference surface during operation. Electromagnetic induction heating is an innovative technology that can replicate a half-circle heating scenario. However, its feasibility must be verified. In this study, we constructed a single receiver tube experimental system using induction heaters and developed a 3D numerical model coupling electromagnetic field to analyze the tube temperature distribution and molten salt temperature rise during preheating and salt circulation, considering various parameters. The results indicated that the numerical simulation agreed well with the experimental results, and the induction heater successfully reproduced the half circumference heating scenario. During preheating, a lower heat flux and higher wind speed result in a more uniform temperature distribution along the circumference of the tube wall, facilitating comprehensive preheating. During salt circulation, the heat flux and inlet salt mass flow significantly affected the temperature of the tube wall but had a relatively small effect on the back-side wall. Wind speed had the opposite effect, which was related to the arrangement of the experimental site. A higher heat flux, lower wind speed, and higher inlet salt mass flow led to a higher temperature increase in the molten salt.

Fenton-like water disinfection using fixed-bed reactor filled with a CoFe2O4 catalyst: Mechanisms, the impact of anions, electromagnetic heating, and toxicity evaluation

This work is a pioneering study demonstrating a promising breakthrough in water disinfection using a cobalt ferrite catalyst in a fixed bed. The performance of CoFe2O4 in E. coli inactivation is due to HO• radicals generated in the Fe3+/Fe2+ and Co3+/Co2+ redox cycles. In contrast to existing reports using cobalt ferrite nanoparticles, the bulk cobalt ferrite provides long-lasting catalytic performance in a flow reactor. The positively charged surface of cobalt ferrite attracts negatively charged E. coli membranes, which enhances disinfection. The CoFe2O4 catalyst was synthesized by the flow co-precipitation method, which allows obtaining kilogram quantities needed for industrial applications. The efficiency of E. coli inactivation was studied as a function of H2O2 concentration. For the first time, the reactor with a CoFe2O4 catalyst was additionally boosted by an electromagnetic field to decompose H2O2 and inactivate bacteria. The electromagnetically heated CoFe2O4/H2O2 system provides a significant 6 log bacterial inactivation. Importantly, cobalt ferrite is very stable under operating conditions. Only a negligible leaching of Fe and Co ions was observed. The presence of inorganic anions was beneficial for the bacterial inactivation. Ecotoxicological analysis revealed the absence of the toxicity of the treated water after using CoFe2O4/H2O2 with electromagnetic heating in the presence of bicarbonate ions. The results show that the magnetic cobalt ferrite is a promising, durable, heterogeneous catalyst for large-scale water disinfection.

Fostering Design for Sustainability through the Adoption of Computer-Aided Engineering Tools in the Development of Energy-Related Products

The main challenge to face in the development of energy-related products is represented by the adoption of effective design for sustainability strategies that encompasses the adoption of engineering design tools, knowledge collection, and reuse/sharing in technical departments. This present paper proposes an engineering design for sustainability methodology that assists engineers in developing energy-related products in compliance with ecodesign standards. The methodology uses virtual prototyping tools to assess energy consumption in compliance with energy labeling directives and analyze different use scenarios. The results obtained by numerical simulations (e.g., Finite Element Method—FEM, Computational Fluid Dynamics—CFD) are used to create specific design eco-knowledge in the field of energy-related products. Numerical results are linked with design configurations to understand the benefits introduced by engineering design choices. This knowledge is stored in a structured database with the aim of being reused when a new product is developed or improved/upgraded. The case study of an induction hob, belonging to the household appliance product family, is investigated to understand the potential and drawbacks of the presented approach in a real application. The results show that potential energy and environmental performance benefits are achieved (e.g., reduction of energy losses, achievement of A+ energy class, and overall life cycle environmental impact reduction). Additionally, a new set of ecodesign guidelines are defined for this product family and employed in developing new compliant products belonging to the same family.

Filter-paper-derived CF/M/C (M = Co, Ni, or Fe/Fe3O4) 2D interlinked frameworks toward ultrawide absorption bands, high thermal conductivity, and excellent electrical insulation

Reasonable design of protective multifunctional materials is highly required for the safety protection of devices/personnel from electromagnetic radiation and heat damage in the 5G/6G era. Herein, a simple soaking-annealing route was adopted to carbonize filter paper into 2D interlinked carbon fiber frameworks inlaid with magnetic nanoparticles, and the products were referred to as CF/M/C 2DIFs (M = Co, Ni, or Fe/Fe3O4). The concentration and type of metal ions as well as the annealing temperature of the CF/M/C 2DIFs were controlled to precisely modulate their composition, porosity, and defects. Results show that the CF/Co/C 2DIFs produced under Ta = 600 °C and [Co2+] = 0.45 mol/L exhibit high thermal conductivity (2.931 ∼ 3.167 W/m·K) at small loads (10 ∼ 30 wt%) owing to not merely the presence of 2D interlinked path for electron/phonon heat co-transfer but the reasonable control of interface/defects for weakening phonon/electron defect/interface scattering. Also, the CF/Co/C 2DIFs can attenuate microwaves over a broad frequency range via dielectric/magnetic dual loss and 2DIFs, which boosts their loss ability and matching performance. The excellent performance in both heat dissipation and EM wave absorption proves that the CF/M/C 2DIFs can be a promising candidate for next-generation electronic packaging materials in heat management, military, and aerospace fields.

Configuration Analysis of Technology Readiness, Technology Acceptance, and Public Satisfaction Regarding Continued Induction Stove Use in Indonesia

In 2022, Indonesia began the energy conversion pilot project from Liquefied Petroleum Gas (LPG) stoves to induction stoves in Surakarta. Before the program is scaled up, it is vital to conduct an in-depth analysis of the technology readiness, technology acceptance, and user satisfaction to assess program continuity. This research aims to identify what configuration of aspects of technology readiness, technology acceptance, and satisfaction will produce continuance intention and the necessary conditions of continuance usage intention. This study involved 412 conversion program participants in five districts in Surakarta, Indonesia. Utilizing fuzzy-set qualitative comparative analysis (fsQCA), four solution configurations that lead to high continuance intention and four for low continuance intention were obtained. Generally, nearly all conditions must be maintained at a positive level to produce high continuance intention, especially innovativeness, and satisfaction. The research has theoretical and practical implications, including satisfaction having the greatest impact on configurations and the quality of the conversion program, in which the induction stove and its service program must become the main focus to ensure satisfaction. Clear policies and wider socialization must be conducted to enhance people’s awareness and trust. To boost sustainability and continuity, synergistic cooperation between stakeholders and the creation of a better environment for induction stove implementation must also be established. Future research should conduct a longitudinal study approach to strengthen the analysis of a long-term induction stove conversion program.

Customer Selection in the Conversion Program of LPG Stove to Induction Stove

The oversupply condition is due to differences in the current electricity supply which is higher than actual electricity demand. One option to increase demand is by converting LPG stoves into induction stoves. To achieve the conversion goal successfully, a customer selection process must be carried out to determine the conversion targets, aiming for a significant increase in electricity demand with the lowest investment costs. The main problem is the absence of a standard for determining conversion targets. The combination of clustering techniques and Multiple Criteria Decision Making (MCDM) analysis provides the best ideal solution to overcome these problems. The research included several main criteria for selecting customers that support the success factors of implementing a conversion program. The initial analysis involved clustering customers based on coordinates using the k-means method. By using the clustered customer data, the TOPSIS (Technique for Ordering Preference by Similarity to an Ideal Solution) method identified the best cluster based on general criteria. Additionally, using detailed customer data, the TOPSIS method also identified the ranking of customer priorities for each selected cluster. The recommended priority target customers are those with the greatest potential for additional kWh, the best level of electricity reliability, shortest distance to the cluster centroid, and supplied by feeders and distribution transformers with the largest reserve margin. The results indicated the difference in revenue improvement compared to the current method was US$ 16,291.31 per month. Investment costs were also reduced by US$ 166,084.80 compared to the current method. The other results were a reduction in operational costs, improvement in average reliability according to the SAIDI SAIFI, improvement in the average operation-hours, and an improvement in the distribution transformer average reserve margins.