Experimental and numerical multidisciplinary methodology to investigate the thermal efficiency of boiling pot on induction system

In this work, a thermal analysis of water boiling using the induction cooking system has been performed. The boiling pot on induction cooker has been simulated by computational fluid dynamics (CFD) with experimental validations. For experimental part, the pot is filled with water and heated by the induction cooker. The temperature of coil, pot, and water is monitored with time varying. For computational part, the multiphase fluid field and solid conduction have been both studied. The heat transfer efficiency of this induction cooking system is estimated as 83.6%. Comparing with experiments, the maximum errors of the bottom pot and coil are 6.1% and 7.9% respectively. The numerical simulation results demonstrate good agreement with experiments. This work offers a better understanding of induction cooking system related dynamics which greatly benefits the practical industry applications.

This study investigates household-scale seawater desalination to address freshwater shortages, particularly in coastal areas or during emergencies. The process involves heating seawater to evaporate it and then condensing the vapor into freshwater. The research compares the efficiency of pure water and salt production from seawater desalination using two heating methods which is gas stoves and induction stoves. Gas stoves which use fossil fuel combustion and induction stoves which use electromagnetic fields to generate heat have different characteristics and efficiencies in the desalination process. After the heating, the seawater then cooling down by using 3 different speed of fan speed.This study evaluates the differences in the amount of pure water and salt produced by these two methods, considering factors such as energy consumption and operational costs. The results of this research are expected to provide useful insights for selecting more efficient and economical heating methods in the seawater desalination process.The results indicate that freshwater production is higher when using an induction stove compared to a gas stove. Freshwater production at low fan speeds yielded 157 g/hour on an induction stove with 600 W power and 147 g/hour on a gas stove with equivalent power of 658.75 W; 168 g/hour on an induction stove with 600 W power and 88 g/hour on a gas stove with equivalent power of 632.92 W; and 153 g/hour on an induction stove with 600 W power and 105 g/hour on a gas stove with equivalent power of 646.58 W. The heating with an induction stove produces more freshwater compared to heating with a gas stove due to its Energy Efficiency, Precise Temperature Control, Heating Speed, Reduced Heat Loss which is better than gas stove.In terms of salt production, both induction and gas stoves produced nearly identical amounts of salt: 34 g/liter on the induction stove and 36 g/liter on the gas stove at low fan speeds; 36 g/liter on the induction stove and 34 g/liter on the gas stove at medium fan speeds; and 34 g/liter on the induction stove and 36 g/liter on the gas stove at high fan speeds. The power required to produce 1 gram of freshwater at low fan speed was 3.57 watts for the induction stove and 7.18 watts for the gas stove; at high fan speed, it needs 3.92 watts for the induction stove and 6.15 watts for the gas stove. Therefore, it can be concluded that the power consumption for the induction stove is significantly lower than that for the gas stove to produce 1 gram of freshwater.

Being the most popular technological framework for the heavy oil and bitumen production, the reservoir heating is mainly performed via steam injection. Progressively it becomes evident, however, that there exist other methods offering an efficient production for various initial reservoir conditions and oil properties. The electromagnetic (EM) heating assisted oil recovery is one of them capable to be an alternative to conventional approaches where they become inacceptable. Physically speaking the radio-frequency (RF) heat generation results from so-called microwave effect i.e. rotation with friction of polar molecules in the EM field. The intrinsic advantages of the RF-heating (RFH) based technology, which in particular avoids the problems associated to water supply and water treatment, can be strengthened by solvent injection. After certain period of preheating this may lead directly to improved oil recovery due to additional oil viscosity drop as a result of oil-solvent mixture process. Along with this the solvent injection may reduce the operational in-situ temperature and thus, to increase the energy efficiency (i.e. the amount of energy required per unit of oil production). This will open a way to the successful technology application in shallow and/or thin reservoir. Mention also that the combination of heat and solvent supply has recently been field-tested. Recently the large-scale EM heating models have been developed for numerical simulation of realistic RFH applications, which provided the technical basis for critical analysis of the oil recovery processes. The numerical methodology based on loose coupling between dedicated reservoir and electromagnetic simulators, has been applied to study the combination (and competition) of two principal physical mechanisms of oil viscosity reduction associated with heat and solvent mass transfer. Taking advantage of the field-scale modelling the evaluation of operational conditions providing the oil production efficiency has been done. It was shown that RFH and its modification can be efficient for the various reservoir conditions. Noticeably different solutions for well configurations can be envisaged in the technology under consideration. The simulations have included the pure RFH cases at variable total EM power and the RFH combination with solvent injection at different operational and well. The initial reservoir conditions and properties corresponded to typical Athabasca reservoir. Main results comprising the methodological aspects of the recent 3D code development, the conclusions on pure RFH advantages and drawbacks and the demonstration of enhanced oil recovery efficiency at solvent injection within the RFH framework, are presented in detail. The role of particular mass transfer mechanisms and their contribution to improved process efficiency in heterogeneous matrix are quantified and discussed. The solvent injection combination with electromagnetic (radio-freqency) heating may become a promising issue in many practical applications.

The efficiency of transmissions is related directly to the energy consumption in vehicle systems. Hence, it is worth a lot researching the overall power losses inside the transmission, in order to modify the transmission performance or optimize the transmission. In most research works, only how to model the component power losses is considered. It is then necessary to put forward a general or standard method to calculate the overall power losses in the transmissions. In this paper, a general model of overall power losses in transmissions is built up, based on the selection of the submodels of component power losses from literature. With the help of the experimental data from the test bench, the methodology of parameter identification is introduced. As a result, more accurate power loss distribution of the transmission is possible to be obtained, through combining the overall efficiency experimental data and the model of overall power losses. In order to validate the methodology, it is applied into two study cases of different transmissions. Through the results of the two study cases, it is concluded that the methodology of modelling of power losses in transmissions with parameter identification is ready to be extended to other transmission study cases. It is expected that with the help of the methodology in this paper, a platform can be built up to benchmark different production transmissions in the future.

A novel power management strategy based on regenerative braking is proposed to make optimal power distribution between fuel cell system and batteries in order to improve the utility of braking energy and decrease the power loss for fuel cell electric vehicle. With the integrated regenerative braking strategy, the novel control algorithm takes the charging power loss from regenerated energy into consideration to develop the power split. Simulation results over different driving cycles are presented to demonstrate that the power loss of components by the novel strategy is further decreased and regenerative energy recuperation is also improved.

Evaluation of retrofitting of an industrial steam cracking furnace by means of CFD simulations

Electricity is mostly used for cooking purposes in developed countries for a long time. Electricity could be used for cooking in Nepalese residential areas by transfering from Liquifty Petroleum Gas (LPG) to Induction Cooking(IC). Significant use of IC to the distribution feeder can increase the losses of the feeder, reducing the voltage profile at the buses, which in fact increases the current-carrying conductor. So, the grid impact analysis by IC loading to the distribution feeder is necessary. The study is carried out by performing technical analysis by load flow analysis on the feeder by calculating current, voltage profile, and power losses. The load flow has been performed for different loading of IC, and optimized Distributed Generation (DG) size is calculated. The bundling of the conductor is performed to reduce the loss at the feeder. This can be performed by checking the rated current of the conductor used (i.e., the branches where the rated current limit violates then that branches need bundling). The power loss at a different penetration level of IC is calculated. The IC power rating of 1500 Watts at each residential consumer when total 4924 number of the consumer is loading to Nagarkot feeder, active power loss increases to 1887.013 kW from 469.443 kW, and reactive power loss increases to 943.507 kVar from 234.722 kVar. The Minimum voltage is 0.664 Per unit (pu) at bus number 104 (Halede bus) which violates the voltage stability limit. The optimal penetration level of IC can be done up to 25% of total peak load by DG integration of 5965 kVA at 0.8 Power Factor (pf) lagging. This will give an active power loss of 530 kW. The next method, i.e., bundling of the conductor in 9 number of branches (at branch number 1, 2, 31, 34, 36, 38, 78, 79, and 86), should be done to improve the IC loading level. The maximum IC loading can be done up to 40% of the total peak load with a power loss of 477.7 kW by this bundling technique.

Researchers' attention has recently been on the best ways to integrate Distributed Generation (DG) into the conventional centralized electrical power distribution systems, particularly in the context of the smart grid idea due to its reputation as a viable remedy for the lack of electric power supply. To optimize the environmental, financial, and technological advantages of DG units’ integration for distribution network operators, it is crucial to determine their ideal position and size. The main objective of this study was to develop and simulate an optimization system for the placement and sizing of distributed generation units in electrical power distribution networks for power losses reduction and voltage profile improvement. The specific objectives were to model and develop the load flow algorithm and codes; develop a meta-heuristic optimization algorithm and codes that selects the best location and size of the DG unit; simulate the nested load flow and optimization algorithms and codes on MATLAB and analyze the effectiveness of the developed algorithm via testing on the standard IEEE 33-bus radial electrical power distribution benchmark network. The Backward-Forward Sweep (BFS) technique was employed in the load flow modelling owing to its maximization of the radial structure of distribution systems. The optimization algorithm was developed based on the Multi-objective Particle swamp optimization (PSO) meta-heuristic technique due to its effective global searching characteristic. The line and load data for the IEEE 33-bus test network being a cutting-edge benchmark for contemporary power distribution networks; were obtained from the Power Systems Test Case Archive- a secondary data source. For this network fed by a synchronous generator, the chosen base MVA (Mega Volt Amp) was 10MVA and the base voltage was 12.66kV. The total active and reactive power demand were 3.715MW and 2.3Mvar respectively. The simulation was done on R2021a version of MATLAB/Simulink. The total real and reactive power losses obtained from base case simulation without the placement of any DG unit in the network were obtained as 201.8925kW and 134.6413kvar respectively while the per unit (p.u) average bus voltage was 0.948594 p.u. After the optimal allocation of one, two, three and four DG units, the total real power loss (in kW) in the network reduced by 140.89, 173.89, 189.89 and 195.89 respectively while the total reactive power loss (in kvar) reduced by 86.64, 114.64, 124,64 and 128.64 respectively. Likewise, the per unit average bus voltage improved by 0.0376p. u, 0.0458p.u, 0.0480p.u and 0.0498p.u respectively. Also, the decrease in the total real and reactive power losses and the improvement in bus voltage profiles varies proportionally with the number of DG units optimally placed. In conclusion, the results shows that the total real power loss and the total reactive power loss of the network, were significantly decreased; and the voltage profile of the system was drastically enhanced by incorporating DG units at predetermined buses. The developed algorithm is recommended for application in a real electrical power distribution network for more efficient integration of new distributed generation units in the current electrical power distribution networks.

Recently, a subsurface technology of in-situ hydrogen production using electromagnetic (EM) heating shows great potential for extracting clean hydrogen directly from natural gas reservoirs. However, critical knowledge gaps persist, particularly in technical assessments. This study addresses these gaps by evaluating energy efficiency, techno-economic viability, and greenhouse gas (GHG) emissions throughout the process. We analyze the system energy efficiency under various experimental conditions using sandstone and synthetic catalysts. The results highlight the potential for field improvements through the optimization of catalysts and methane flow rates. Techno-economic analysis (TEA), based on a developed reservoir-scale model, indicates hydrogen production cost can be potentially as low as $0.86/kg with the integration of renewable energy. Key cost drivers include membrane expenses and EM-heating electricity for hydrogen production. Life cycle assessment (LCA) indicates that methane pyrolysis in gas reservoirs does not generate GHG emissions throughout its life cycle. However, GHG emissions associated with electricity use (i.e., EM heating) in the process should be considered. Moreover, the technology's eligibility for Section 45 V of Inflation Reduction Act (IRA 45 V) clean hydrogen credits is contingent upon the source of electricity used. And the qualification for the credits depends on the proportion of renewable energy in the electricity consumption mix. This study provides insights into efficiency optimization, cost competitiveness, and environmental considerations for in-situ hydrogen production from gas reservoirs using EM heating.

Electromagnetic (EM) heating is an advanced technology that can improve the oil recovery rate. Previous studies usually focus on the coupling of EM and thermal reservoir models, with little attention to multi-phase flow in EM heating. In order to accurately analyze the heat and mass transfer in the reservoir under EM heating, this work developed an advanced model coupling the EM-temperature-seepage fields, in which the variation of the physical properties of heavy oil reservoirs has been considered. In addition, the influence of the EM heating factors is also analyzed. The results show a significant saturation partitioning in the heat and mass transfer in heavy oil reservoirs under EM heating, and heavy oil flows more rapidly in areas of high oil saturation. Increasing the EM frequency and power can extend the heating range of the reservoir, but it can cause a dramatic rise in the temperature of the antenna. When the temperature of the production well induces heavy oil flow, increasing the production pressure can significantly improve output. The average flow rate of heavy oil at the producing well increased by 17.61% when the bottom flow pressure decreased from 19 MPa to 17 MPa. The study of the distance between the production well and the antenna finds that the average temperature of the production well is only 463.06 K when the antenna spacing is 15 m. Compared with other situations, 10 m is the most suitable for efficient and continuous exploitation of heavy oil.

Heat transfer and performance analysis of nanofluid flow in helically coiled tube heat exchangers

Due to the complexity of interactions between microwaves and food products, a reliable and efficient simulation model can be a very useful tool to guide the design of microwave heating systems and processes. This research developed a model to simulate coupled phenomena of electromagnetic heating and conventional heat transfer by combining commercial electromagnetic software with a customer built heat transfer model. Simulation results were presented and compared with experimental results for hot water and microwave heating in a single mode microwave system at 915 MHz. Good agreement was achieved, showing that this model was able to provide insight into industrial electromagnetic heating processes.

Multi-hob induction cooking systems can achieve a high degree of complexity. Since they are made up of analogical and digital blocks, a mixed-signal environment is needed for modeling and simulation. The modeling issue can be approached at different levels of abstraction and accuracy: various allowable solutions are considered and some of them (Matlab/Simulink, VHDL, VHDL-AMS and an extension of SystemC to analog mixed-signal), are employed in the modeling process of an induction cooking basic system.

Simultaneous electromagnetic radiation and nanofluid injection and their interactions in EOR operations: A comprehensive review

In the process of power supply to final consumers, an important amount of energy is lost in the transmission and distribution systems due to technological and non-technological losses. These power losses are often referred to as "line losses", even if line losses represent only one type of power loss that occurs during the process of transmission and distribution of electricity. Each component of the power transmission and distribution system contributes to losses, so that a reduction in loss at the final consumer will be felt significantly at the generation level. Technical losses represent an economic loss with environmental effects at national level, and its optimization should be performed from an overall national's perspective, regardless of the institutional organization of the sector and ownership of operating electricity utilities [1]. EU Energy Efficiency Directive 27/CE/2012 states for an important obligation for utility companies to improve energy efficiency in delivering services to their customers. The Directive establishes a common framework of measures to promote energy efficiency within the Union in order to ensure the achievement of the 20% target for energy efficiency by 2020 and to pave the way for the future growth of energy efficiency beyond that date [2]. The volume of energy losses in the power transmission and distribution systems is important, as it is generally up to 3-13%. The volume of power losses in Romanian power transmission and distribution systems is important, the level being of about double to the average in Europe. The current paper presents the research results of the authors regarding the real time monitoring and analysis systems for power losses, in electrical transmission and distribution systems.