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Chinese Journal of Chemical Engineering 2017年第9期25卷 1137-1142页

作者： S.R.Mishra M.M.Bhatti Department of Mathematics Siksha ‘O’ Anusandhan University Shanghai Institute of Applied Mathematics and Mechanics Shanghai University

In this article, we have considered the simultaneous influence of ohmic heating and chemical reaction on heat and mass transfer over a stretching sheet. The effects of applied magnetic field are also taken into consideration while the induced magnetic field is not considered due to very small magnetics Reynolds number. The governing flow problem comprises of momentum, continuity, thermal energy and concentration equation which are transformed into highly nonlinear coupled ordinary differential equations by means of similarity transforms, which are then, solved numerically with the help of Successive Linearization method(SLM) and Chebyshev Spectral collocation method. Numerical values of skin friction coefficient, local Nusselt number, and Sherwood number are also taken into account with the help of tables. The physical influence of the involved parameters of flow velocity, temperature and concentration distribution is discussed and demonstrated graphically. The numerical comparison is also presented with the existing published results and found that the present results are in excellent agreement which also confirms the validity of the present methodology.

关键词： ohmic heating Heat and mass transfer Chemical reaction Successive linearization method

Changes in electrical conductivity of liquid foods during ohmic heating

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International Journal of Agricultural and Biological Engineering 2014年第5期7卷 133-138页

作者： Shivmurti Srivastav Srishti Roy Department of Food Processing Technology A.D.Patel Institute of TechnologyNew Vallabh Vidya NagarAnandGujarat 388121India

ohmic heating is a food processing method in which alternating current(AC)went through a food sample and resulted in internal energy generation in *** is an alternative fast heating *** principal advantage is the ability to rapidly and uniformly heat food materials of various *** ohmic heating,change in electrical conductivity was *** intensity of food materials’electrical conductivity or overall resistance critically controls ohmic heating *** ohmic heating set-up was prepared under this *** juice was heated(about 32℃ to 80℃)in a batch type ohmic heater at different voltage gradients in the range of 50-70 V/*** was statistically found that the voltage gradient had significant impact on conductivity and system performance coefficient(SPC)(P<0.05).It was concluded that the electrical conductivity values linearly increased with *** SPCs of the system ranged between 0.779 and *** value of R2 of the linear model was greater than 0.98.

关键词： ohmic heating electrical conductivity thermal conductivity liquid foods

Hall,ion slip and ohmic heating effects in thermally active sinusoidal channel

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Propulsion and Power Research 2019年第3期8卷 263-273页

作者： S.Noreen T.Kousar Department of Mathematics COMSATS University IslamabadPark RoadTarlai KalanIslamabad 45550Pakistan

In this paper Carreau fluid is taken into account to study its peristaltic flow with Hall and ion-slip *** study is carried out in a wave frame of reference for both asymmetric and symmetric *** of heat transfer is accomplished by taking the effects of viscous dissipation and ohmic heating into our *** of fundamental equations is followed by the construction of closed form solutions for pressure gradient,stream function and temperature while assuming Reynold's number is very low and wavelength very *** closed form solutions are generated with the help of perturbation technique considering Weissenberg number to be very *** effects of emerging parameters on pumping,trapping,axial pressure gradient,pressure rise,velocity profile and temperature are analyzed through the graphical representation.

关键词： Hall effect Ion slip ohmic heating Perturbation method

On radiative-magnetoconvective heat and mass transfer of a nanofluid past a non-linear stretching surface with ohmic heating and convective surface boundary condition

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Propulsion and Power Research 2016年第4期5卷 326-337页

作者： Shweta Mishra Dulal Pal Hiranmoy Mondal Precious Sibanda School of Engineering and Technology Amity UniversityNew TownKolkataWest Bengal 700135India Department of Mathematics Institute of ScienceVisva-Bharati(A Central University)SantiniketanWest Bengal 731235India School af Mathematics Statistics and Computer ScienceUniversity of KwaZulu-NatalPrivate Bag X01ScottsviUePietermaritzburg 3209South Africa

In this paper magnetoconvective heat and mass transfer characteristics of a two-dimensional steady flow of a nanofluid over a non-linear stretching sheet in the presence of thermal radiation,ohmic heating and viscous dissipation have been investigated *** model used for the nanofluid incorporates the effects of the Brownian motion and the presence of nanopanicles in the base *** governing equations are transformed into a system of nonlinear oidinary differential equations by using similarity *** numerical solutions are obtained by using fifth order Runge-Kutta-Fehlberg method with shooting *** non-dimensional parameters on velocity,temperature and concentration profiles and also on local Nusselt number and Sherwood number are *** results indicate that the local skin friction coefficient decreases as the value of the magnetic parameter increases whereas the Nusselt number and Sherwood number increase as the values of the Brownian motion parameter and magnetic parameter increase.

关键词： Nanofluid Magnetoconvection Thermal radiation Non-linear stretching sheet ohmic heating

Initial testing of ohmic heating through double flux swing during electron cyclotron start-up in the QUEST spherical tokamak

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Plasma Science and Technology 2023年第5期25卷 31-36页

作者：张逸凡 Takumi ONCHI Kazuo NAKAMURA 岳其霖 Takahiro NAGATA Shoji KAWASAKI Kengoh KURODA Makoto HASEGAWA Ryuya IKEZOE Takeshi IDO Kazuaki HANADA Hiroshi IDEI Interdisciplinary Graduate School of Engineering Sciences Kyushu UniversityKasuga 816-8580Japan Research Institute for Applied Mechanics Kyushu UniversityKasuga 816-8580Japan

A power-supply system was developed for ohmic heating(OH)to double×10^(18)the amount of change magnetic flux in the primary central solenoid(CS)on the QUEST spherical *** power supplies are connected with stacks of insulated-gate bipolar transistors,and sequentially operated to generate positive and negative CS *** bipolar power-supply system is controlled via a field-programmable gate array,which guarantees the safety of the entire system *** new OH system,assisted by electron cyclotron heating,enables the stable generation of plasma currents exceeding 100 k ***,the achieved electron density over the wide range in the major radial direction exceeds the cut-off density for one of the highpower microwave sources in *** strategy yields target plasmas for future experiments with the electron Bernstein wave.

关键词： spherical tokamak ohmic heating electron cyclotron heating FPGA

Modelling and Simulation of an ohmic heating Process

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Open Journal of Modelling and Simulation 2021年第1期9卷 26-42页

作者： Hongwei Zhang Ahmed Mohamed Timofei Breikin Martin Howarth National Centre of Excellence for Food Engineering Sheffield Hallam University Sheffield UK

ohmic heating (OH) is one of the emerging thermal technologies used in food processing which can produce rapid and uniform heating with close to 100% energy transfer efficiency. Although mathematical modelling for OH processes has been studied by many researchers in recent years, systematic simulations of OH have not been developed for model-based control of the processes. In this paper, mathematical model for a Colinear Ohmic Heater is presented, analyzed, and studied based on the selected configuration. A numerical solution for the mathematical equations has been defined and proposed. MATLAB/Simulink model is hence developed and validated against the available data. Simulation results have shown that MATLAB/Simulink model can produce robust outputs at low computational costs with an accuracy of up to 99.6% in comparison to the analytical solution. This model can be used in further studies for analysis of the OH processes and development of advanced controllers.

关键词： ohmic heating Colinear ohmic Heater Mathematical Modelling Numerical Solution MATLAB/Simulink Simulations

Magnetic probe diagnostics of nonlinear standing waves and bulk ohmic electron power absorption in capacitive discharges

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Plasma Science and Technology 2021年第11期23卷 74-83页

作者： Kai ZHAO Yongxin LIU Quanzhi ZHANG Demetre J ECONOMOU Younian WANG Key Laboratory of Materials Modification by Laser Ionand Electron Beams(Ministry of Education)School of PhysicsDalian University of TechnologyDalian 116024People's Republic of China Plasma Processing Laboratory William A.Brookshire Department of Chemical and Biomolecular EngineeringUniversity of HoustonHoustonTexas 77204-4004United States of America

It is recognized that standing wave effects appearing in large-area,very-high-frequency capacitively coupled plasma(CCP)reactors cause center-high plasma *** a high-frequency magnetic probe,we present a direct experimental diagnostic of the nonlinear standing waves and bulk ohmic electron power absorption dynamics in low pressure CCP discharges for different driving frequencies of 13.56,30,and 60 *** design,principle,calibration,and validation of the probe are described in *** structures of the harmonics of the magnetic field,determined by the magnetic probe,were used to calculate the distributions of the harmonic current and the corresponding ohmic electron power deposition,providing insights into the behavior of nonlinear *** a low driving frequency,i.e.13.56 MHz,no remarkable nonlinear standing waves were identified and the bulk ohmic electron power absorption was observed to be *** harmonic magnetic field/current was found to increase dramatically with the driving frequency,due to decreased sheath reactance and more remarkable nonlinear standing waves at a higher driving frequency,leading to the enhancements of the ohmic heating and the plasma density in the bulk,specifically at the electrode *** a high driving frequency,i.e.60 MHz,the high-order harmonic current density and the corresponding ohmic electron power absorption exhibited a similar node structure,with the main peak on axis,and one or more minor peaks between the electrode center and the edge,contributing to the center-high profile of the plasma density.

关键词： capacitively coupled plasmas magnetic probe nonlinear standing waves ohmic heating

Energy Confinement of both ohmic and LHW Plasma on EAST

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Plasma Science and Technology 2011年第3期13卷 312-315页

作者：杨曜高翔 EAST team Institute of Plasma Physics Chinese Academy of Sciences Hefei 230031 China

Study on the characters of energy confinement in both ohmic and lower hybrid wave （LHW） discharges on EAST is conducted and the linear ohmic confinement （LOC）, saturated ohmic confinement （SOC） and improved ohmic confinement （IOC） regimes are investigated in this paper. It is observed that an improved confinement mode characterized by both a drop of IDa line intensity and an increase in line average density can be triggered by a gas puffing pulse.

关键词： energy confinement LHW plasma ohmic heating EAST

Novel heating technologies to improve fermentation efficiency and quality in wheat products:A short review

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Grain & Oil Science and Technology 2021年第2期4卷 81-87页

作者： Zhen Wang Jihong Huang Sen Ma Xiaoxi Wang Binghua Sun Fengcheng Wang Li Li Qingdan Bao College of Food Science and Engineering Henan University of TechnologyZhengshou 450001China

Identifying novel processing methods is an important research direction in the field of food *** flour products have been popular all over the world for a long time because of their unique flavor and *** for yeast or sourdough,the accurate temperature control is essential for the fermentation *** novel heating methods have shown potential in the processing of fermented flour *** heating(MWH),radiofrequency heating(RFH),and ohmic heating(OH)are undoubtedly the most promising heating *** affects the fermentation time of the dough by affecting the water molecules in the dough,and may also improve the fermentation quality of wholewheat flour *** contributes to the control of harmful substances in the fermentation process and has shown potential for the production of sourdough *** has superiority in accurately controlling the temperature,enzymes,microorganisms,*** the fermentation process,and it is beneficial to shortening the fermentation *** have applied these heating methods with different properties to different *** article summarized the application and potential of these three novel heating methods in the production of fermented flour *** application scenarios and parameter settings of novel heating technologies in dough fermentation process need further *** is reasonable to believe that novel heating methods can become an important tool to improve the efficiency of dough fermentation and the quality of fermented dough in the future.

关键词： Microwave heating Radiofrequency heating ohmic heating Novel heating technology of fermentation

Initial Plasma Startup Test on SUNIST Spherical Tokamak

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Plasma Science and Technology 2003年第6期5卷 2017-2022页

作者：王莹曾立何也熙 SUNIST Team Department of Engineering Physics Tsinghua University Beijing 100084

The goal of the Sino-United Spherical Tokamak (SUNIST) at Tsinghua University is to extend the understanding of toroidal plasma physics at a low aspect ratio (R/a≈1.3) and to demonstrate a maintainable target plasma by non-inductive startup. The SUNIST device is designed to operate with up to 13 kA of ohmic heating field current, and to 0.15 T of toroidal field at 10 kA of discharge current. All of the poloidal fields can provide 30 mVs of Volt-seconds transformer. Experimental results of plasma startup show that SUNIST has remarkable characteristics of high ramp rate (dIp/dt≈50 MA/s ), high normalized current In of about 2.8 (In = Ip/αBt), and high-efficiency (Ip/Irod ≈0.4) production of plasma current while operating at a low toroidal field. Major disruption phenomena have not been observed from magnetic diagnostics of all testing shots. Initial discharges with 52 kA of plasma current (exceeding the designed value of 50 kA), 2 ms of pulse length and 50 MA/s of ramp rate have been achieved easily with pre-ionized filament.

关键词： ohmic heating plasma startup SUNIST spherical tokamak