Computational analysis of temperature distribution in microwave-heated potatoes

2020 ◽  
Vol 26 (6) ◽  
pp. 465-474
Author(s):  
Deepak Singh ◽  
Dhananjay Singh ◽  
Sattar Husain
Keyword(s):  
Mathematical Model ◽  
Temperature Distribution ◽  
Computational Analysis ◽  
Three Dimensional ◽  
Dimensional Structure ◽  
Maximum Temperature ◽  
Bacterial Inactivation ◽  
Food Material ◽  
Drying Time ◽  
Temperature Ranges

This research article reports the computational analysis of temperature distribution in microwave-heated convenience food such as potato. The detailed study of temperature (because temperature is a function of bacterial inactivation) and microwave powers along with drying time for the preservation of food material has been presented. Therefore, a mathematical model for potato sample is developed to predict the behavior of temperature distribution at each possible point and different shapes (slab, cylindrical, and spherical) of food material. The developed mathematical model is programmed by MATLAB software. Another parameter, microwave power is also a function of temperature. The ranging values of various microwave powers (125 W, 375 W, 625 W, 875 W, and 1250 W) along with different values of drying time (0 to 10 minutes) have been used for computation. The obtained results show the uniformity of temperature distribution throughout the whole product in the form of a three-dimensional structure. The model provides the minimum and maximum temperature ranges in specimens without performing an experiment which depicts the condition of bacterial inactivation.

Electromagnetic performance and thermal analysis of a novel permanent magnet fluxed-switching coupler

2021 ◽  
pp. 1-18
Author(s):  
Lezhi Ye ◽  
Yulong Zhang ◽  
Mingguang Cao
Keyword(s):  
Temperature Distribution ◽  
Permanent Magnet ◽  
Permanent Magnets ◽  
Three Dimensional ◽  
Load Condition ◽  
Maximum Load ◽  
Maximum Temperature ◽  
The Novel ◽  
Transient Field ◽  
Three Dimensional Finite Element

To solve the problem of complex operating device and permanent magnets (PMs) demagnetization at high temperature, a new type of permanent magnet fluxed-switching coupler (PMC) with synchronous rotating adjuster is proposed. Its torque can be adjusted by rotating a switched flux angle between the adjuster and PMs along the circumferential direction. The structural feature and working principle of the PMC are introduced. The analytical model of the novel PMC was established. The torque curves are calculated in transient field by using the three-dimensional finite element method (3-D FEM). The temperature distribution of the novel PMC under rated condition is calculated by 3-D FEM, and the temperature distribution of the PM is compared with that of the conventional PMC. The simulation and test results show that the maximum temperature of copper disc and PM of the novel PMC are 100 °C and 48 °C respectively. The novel PMC can work stably for a long time under the maximum load condition.

scholarly journals Numerical Simulation and Experimental Study on Temperature Distribution of Self-Lubricating Packing Rings in Reciprocating Compressors

2016 ◽  
Vol 2016 ◽  
pp. 1-14 ◽  
Author(s):  
Jia Xiaohan ◽  
Zhang Qingqing ◽  
Feng Jianmei ◽  
Peng Xueyuan
Keyword(s):  
Temperature Distribution ◽  
Pressure Ratio ◽  
Three Dimensional ◽  
Maximum Temperature ◽  
Transfer Model ◽  
Radial Temperature ◽  
Operational Conditions ◽  
External Cooling ◽  
Packing Rings ◽  
Compressor Reliability

The nonuniform abrasion failure and high-temperature thermal failure of packing rings have a significant influence on compressor reliability, particularly that of oil-free compressors. In this study, a test rig was constructed to measure the dynamic temperature of packing rings under different operational conditions in an oil-free reciprocating compressor. The dynamic axial and radial temperature distributions of the packing rings were obtained using an innovative internal temperature testing device that kept the thermocouples and packing box relatively static during compressor operation. A three-dimensional heat transfer model was also developed to analyze the temperature distribution of the packing boxes, piston rod, and cylinder during such operation. Good agreement was observed between the simulation results and experimental data, which showed an average relative error of less than 2.35%. The results indicate that the pressure ratio exerts a significant effect on the axial temperature distribution and determines which packing ring reaches the maximum temperature. They also show the average temperature to rise with an increase in the rotational speed and to fall with an improvement in the external cooling conditions. Finally, the material of the packing rings was found to affect the temperature gradient from their inner to outer surface.

Fabrication of a Cell Culture Plate With a Three-Dimensional Printed Mold and Thermal Analysis of PDMS-Based Casting Process

2018 ◽  
Vol 10 (6) ◽  
Author(s):  
Myo Min Zaw ◽  
William D. Hedrich ◽  
Timothy Munuhe ◽  
Mohamad Hossein Banazadeh ◽  
Hongbing Wang ◽  
...  
Keyword(s):  
Cell Culture ◽  
Temperature Distribution ◽  
Fused Deposition Modeling ◽  
Thermal Damage ◽  
Elevated Temperatures ◽  
Three Dimensional ◽  
Curing Temperature ◽  
Maximum Temperature ◽  
Maximum Temperature Difference ◽  
Fused Deposition

Abstract Polydimethylsiloxane (PDMS)-based casting method was used to fabricate PDMS cell culture platforms with molds printed by a fused deposition modeling (FDM) printer. Cell viability study indicated that the produced plates have the suitable biocompatibility, surface properties, and transparency for cell culture purposes. The molds printed from acrylonitrile-butadiene-syrene (ABS) were reusable after curing at 65 °C, but were damaged at 75 °C. To understand thermal damage to the mold at elevated temperatures, the temperature distribution in an ABS mold during the curing process was predicted using a model that considers conduction, convection, and radiation in the oven. The simulated temperature distribution was consistent with the observed mold deformation. As the maximum temperature difference in the mold did not change appreciably with the curing temperature, we consider that the thermal damage is due to the porous structure that increases the thermal expansion coefficient of the printed material. Our study demonstrated that FDM, an affordable and accessible three-dimensional (3D) printer, has great potential for rapid prototyping of custom-designed cell culture devices for biomedical research.

scholarly journals Investigation on Smoke Flow in Stairwells induced by an Adjacent Compartment Fire in High Rise Buildings

2019 ◽  
Vol 9 (7) ◽  
pp. 1431 ◽  
Author(s):  
Jun Zhang ◽  
Jingwen Weng ◽  
Tiannian Zhou ◽  
Dongxu Ouyang ◽  
Qinpei Chen ◽  
...  
Keyword(s):  
Temperature Distribution ◽  
Three Dimensional ◽  
Factor H ◽  
Maximum Temperature ◽  
Vertical Temperature ◽  
Location Factor ◽  
Index Model ◽  
Smoke Flow ◽  
Vertical Temperature Distribution ◽  
Fire Location

The aim of this study was to evaluate the transport phenomena of smoke flow and vertical temperature distribution in a 21-story stairwell with multiple fire locations and openings. A large eddy simulation (LES) method was used to model the smoke flow in a stairwell model with a set of simulation parameters, wherein the fire heat release rate (HRR) and fire location were varied. Based on the results, a wall attachment effect was found in three-dimensional figures. Moreover, with an increase in the fire HRR, the effects were more pronounced. The simulation results verified that the vertical temperature distribution is an index model with a natural logarithm, where the pre-finger factor and attenuation coefficient increase considerably in accordance with an increase in the fire HRR. Moreover, there was a decrease in the maximum temperature (Tm) with an increase in the fire location factor (h*) due to the upward thermal smoke. Moreover, heat mainly accumulates in the area above a fire source. However, h* has a slight influence on the time required to reach Tm within the range of 53–64 s. Furthermore, the direction of the airflow at each side opening in the stairwell varied in accordance with the variation in the fire location changes, and a regular calculation was carried out.

scholarly journals An improved two-rotor function for conformational potential energy surfaces of 20 amino acid diamides

2018 ◽  
Vol 96 (1) ◽  
pp. 58-71 ◽  
Author(s):  
John Justine S. Villar ◽  
Adrian Roy L. Valdez ◽  
David H. Setiadi ◽  
Imre G. Csizmadia ◽  
Béla Viskolcz ◽  
...  
Keyword(s):  
Mathematical Model ◽  
Amino Acid ◽  
Potential Energy ◽  
Potential Energy Surfaces ◽  
Three Dimensional ◽  
Potential Energy Function ◽  
Dimensional Structure ◽  
Molecular Forces ◽  
Computational Resources ◽  
Energy Surfaces

Predicting the three-dimensional structure of a protein from its amino acid sequence requires a complete understanding of the molecular forces that influences the protein folding process. Each possible conformation has its corresponding potential energy, which characterizes its thermodynamic stability. This is needed to identify the primary intra- and inter-molecular interactions, so that we can reduce the dimensionality of the problem, and create a relatively simple representation of the system. Investigating this problem using quantum chemical methods produces accurate results; however, this also entails large computational resources. In this study, an improved two-rotor potential energy function is proposed to represent the backbone interactions in amino acids through a linear combination of a Fourier series and a mixture of Gaussian functions. This function is applied to approximate the 20 amino acid diamide Ramachandran-type PESs, and results yielded an average RMSE of 2.36 kJ mol−1, which suggest that the mathematical model precisely captures the general topology of the conformational potential energy surface. Furthermore, this paper provides insights on the conformational preferences of amino acid diamides through local minima geometries and energy ranges, using the improved mathematical model. The proposed mathematical model presents a simpler representation that attempts to provide a framework on building polypeptide models from individual amino acid functions, and consequently, a novel method for rapid but accurate evaluation of potential energies for biomolecular simulations.

Accurate Predetermination of the Process Parameters for Glass/Glass Laser Bonding Based on the Temperature Distribution Analysis

2016 ◽  
Vol 138 (2) ◽  
Author(s):  
Yanyi Xiao ◽  
Wen Wang ◽  
Jianhua Zhang
Keyword(s):  
Finite Element ◽  
Temperature Distribution ◽  
Three Dimensional ◽  
Maximum Temperature ◽  
Thermal Imager ◽  
Distribution Analysis ◽  
Analysis Model ◽  
Glass Laser ◽  
Element Analysis ◽  
Laser Bonding

Temperature distribution is the key factor affecting the bonding quality in the glass/glass laser bonding process. In this work, the finite element method was used to establish three-dimensional (3D) numerical analysis model of the temperature field during bonding. Based on the result of the finite element analysis, the crucial parameters and their influences on the temperature distribution were discussed. In order to predetermine the necessary process parameter values for bonding, a nonlinear multiparameter fitting formula was established to predict the maximum temperature. The fitting model was validated experimentally by recording the maximum temperature during laser bonding via an infrared thermal imager.

Dehydration Characteristics of Cauliflower

2007 ◽  
Vol 3 (6) ◽  
Author(s):  
Vishvambhar Dayal Mudgal ◽  
Vishakha Kalidas Pande
Keyword(s):  
Ascorbic Acid ◽  
Moisture Content ◽  
Ascorbic Acid Content ◽  
Moisture Diffusivity ◽  
Significant Loss ◽  
Food Material ◽  
Drying Time ◽  
Drying Characteristics ◽  
Air Temperatures ◽  
Temperature Ranges

Experiments were conducted to study the drying characteristics of raw cauliflower florets. A mechanical tray dryer was used in this study. The samples were dehydrated at 60, 70, 80 and 90°C air temperatures with blanching pretreatment of two minutes in 0.75 per cent potassium metabisulphite. Drying characteristics were determined with the help of mass transfer data. Moisture content of cauliflower was found to decrease rapidly during the initial 150 minutes. Cauliflower behaved like a hygroscopic non-porous food material during the drying. Drying time of 330 to 510 minutes was required to reduce the moisture content from 92.50 per cent to 5.00 - 6.00 per cent. The moisture diffusivity during drying process was determined and found in the range of 2.54 x10-12 to 3.80 x10-12 m2/s. Quality of the dehydrated samples such as carbohydrate content, ascorbic acid retention and rehydration were also evaluated. The carbohydrate and ascorbic acid content in dehydrated samples ranged from 3.25 to 3.45 g per 100 g and 39.75 - 24.10 mg / 100 g as against 5.40 g / 100 g and 55.55 mg / 100 g respectively, in fresh vegetable indicating a significant loss of nutrients during processing. Product was found to be good in terms of appearance and taste up to 60 days for all the four temperature ranges.

Three-Dimensional Finite Element Analysis in Cutting Temperature for High Speed Milling of Titanium Alloys

2011 ◽  
Vol 189-193 ◽  
pp. 2259-2263
Author(s):  
You Xi Lin ◽  
Cong Ming Yan
Keyword(s):  
Finite Element ◽  
Temperature Distribution ◽  
Titanium Alloys ◽  
High Speed ◽  
Three Dimensional ◽  
Cutting Temperature ◽  
Maximum Temperature ◽  
Depth Of Cut ◽  
High Speed Milling ◽  
Radial Depth

A three dimensional fully thermal-mechanical coupled finite element model had been presented to simulate and analyze the cutting temperature for high speed milling of TiAl6V4 titanium alloy. The temperature distribution induced in the tool and the workpiece was predicted. The effects of the milling speed and radial depth of cut on the maximum cutting temperature in the tool was investigated. The results show that only a rising of temperature in the lamella of the machined surface is influenced by the milling heat. The maximum temperature in the tool increases with increasing radial depth of cut and milling speed which value is 310°C at a speed of 60 m/min and increases to 740°C at 400m/min. The maximum temperature is only effective on a concentrated area at the cutting edge and the location of the maximum temperature moves away from the tool tip for higher radial depths of milling. The predicted temperature distribution during the cutting process is consistent with the experimental results given in the literature. The results obtained from this study provide a fundamental understanding the process mechanics of HSM of titanium alloys.

scholarly journals Mathematical Model of a Three-Dimensional Non-Isothermal Glacier

1976 ◽  
Vol 17 (77) ◽  
pp. 401-418 ◽  
Author(s):  
S. S. Grigoryan ◽  
M. S. Krass ◽  
P. A. Shumskiy
Keyword(s):  
Boundary Layer ◽  
Mathematical Model ◽  
Temperature Distribution ◽  
Small Parameter ◽  
Three Dimensional ◽  
Thin Boundary Layer ◽  
Determinate System ◽  
Isothermal Case ◽  
Orthogonal Coordinates

A mathematical model is constructed for land glaciers with the thickness much less than the horizontal dimensions and radii of curvature of large bottom irregularities by means of the method of a thin boundary layer in dimensionless orthogonal coordinates. The dynamics are described by a statically determinate system of equations, so the solution for stresses is found. For the general non-isothermal case the interrelated velocity and temperature distributions are calculated by means of the iteration of solutions for velocity and for temperature. Temperature distribution is determined by a parabolic equation with a small parameter at the senior derivative. Its solution is reduced to the solution of a system of recurrent non-uniform differential equations of the first order by means of a series expansion of the small parameter. A relatively thin conducting boundary layer adjoins the upper and lower surfaces of a glacier, playing the role of a temperature damper in the ablation area. For ice divides, the statically indeterminate problem is solved, so the result for stresses depends on the temperature distribution.

scholarly journals The Mathematical Model of Coupling Calculation the Electromagnetic Field and Heats of End Zone Powerful Turbogenerator

2019 ◽  
Vol 62 (1) ◽  
pp. 37-46 ◽  
Author(s):  
O. H. Kensytskyi ◽  
D. I. Hvalin ◽  
K. O. Kobzar
Keyword(s):  
Mathematical Model ◽  
Electromagnetic Field ◽  
Reactive Power ◽  
Three Dimensional ◽  
Central Zone ◽  
Shielding Effect ◽  
Design Stage ◽  
Maximum Temperature ◽  
Two Dimensional ◽  
Stator Core

A quasi-three-dimensional field mathematical model of the electromagnetic field and heat transfer processes in end zone of a powerful turbogenerator has been developed. A model is the intermediate version between two-dimensional and three-dimensional solutions and is based on the numeral calculations in transversal and longitudinal sections of turbogenerator, interconnected by a complex of boundary conditions. On the first stage, a two-dimensional field model of the electromagnetic field in transversal section of central zone of a turbogenerator is considered. Then, taking into account the field distribution in central part, the magnetic field in longitudinal section is simulated. In response to the symmetry of the machine along axial and radial directions, the calculation area of end zone is considered as a half of the rotor section along its axis and the section of the stator core tooth in the tangential direction (circumferentially). Having taken the distribution of electromagnetic parameters obtained in the load mode of the machine as the initial data, the thermal losses in the elements and nodes of the end zone are determined. As a result of solving the joint problem of calculating the electromagnetic field and heat exchange processes, the distribution of heating has been obtained not only on the surface, but also inside the structural parts of the end zone. In particular, it has been found that the maximum temperature of 97.3 °C takes place in the tooth area of the end package of the stator core. This is explained by the combined effect of the main radial field, the axial leakage flux of the frontal portions of the stator and rotor windings, as well as by the “buckling” of a portion of the main flux out of the air gap. In addition, the pressure plate shielding effect is the cause of local field concentration in the toothed zone of the end package. The presented model makes it possible as early as at the design stage to evaluate the efficiency of design solutions for the formation of the end zone of the turbogenerator stator for different load modes of the machine, including the modes of consumption of reactive power.

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