Modeling time-temperature history and sterilization value of mango puree under conventional and microwave assisted pasteurization

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Tamires K. Oishi ◽  
Jorge A. W. Gut
Keyword(s):  
Microwave Heating ◽  
Process Analysis ◽  
Residual Activity ◽  
High Energy ◽  
Temperature History ◽  
Design And Optimization ◽  
Nutritional Characteristics ◽  
Mass Dispersion ◽  
Flow Heat ◽  
Helical Tubes

Abstract Continuous pasteurization of liquid foods has to provide the desired lethality level to guarantee food safety with minimum degradation of quality attributes (sensorial and nutritional characteristics) and high energy efficiency. To optimize quality and cost, a thermal process should be modeled considering flow, heat transfer and mass dispersion principles; however, flow through helical tubes and microwave heating require a complex 3D multiphysics approach. Herein a simplified 2D approach is presented to model a hybrid pasteurization unit with conventional and microwave heating under laminar flow to predict axial and radial distributions of temperature and residual activity of a microorganism or enzyme. A study case of 20 °Brix mango puree (power law fluid) processing is used to test the model based on an existing pilot plant unit. Results were useful to compare conventional and microwave heating regarding the process sterilization value and model can be used for process analysis, design and optimization.

scholarly journals Modeling and Measurement of Thermal Effect in a Flashlamp-Pumped Direct-Liquid-Cooled Split-Disk Nd:LuAG Ceramic Laser Amplifier

Photonics ◽  
2021 ◽  
Vol 8 (4) ◽  
pp. 97
Author(s):  
Shengzhe Ji ◽  
Wenfa Huang ◽  
Tao Feng ◽  
Long Pan ◽  
Jiangfeng Wang ◽  
...  
Keyword(s):  
Thermal Stress ◽  
Thermal Effects ◽  
Thermal Deformation ◽  
High Energy ◽  
Gain Medium ◽  
Wavefront Aberration ◽  
Experimental Measurements ◽  
Laser Amplifier ◽  
Design And Optimization ◽  
Ceramic Laser

In this paper, a model to predict the thermal effects in a flashlamp-pumped direct-liquid-cooled split-disk Nd:LuAG ceramic laser amplifier has been presented. In addition to pumping distribution, the model calculates thermal-induced wavefront aberration as a function of temperature, thermal stress and thermal deformation in the gain medium. Experimental measurements are carried out to assess the accuracy of the model. We expect that this study will assist in the design and optimization of high-energy lasers operated at repetition rate.

Gibbs Systems Dynamics: A Simple But Powerful Tool for Process Analysis, Design and Optimization

2002 ◽  
Author(s):  
Pierre Neveu ◽  
Nathalie Mazet
Keyword(s):  
Process Analysis ◽  
Irreversible Processes ◽  
Systems Dynamics ◽  
Vapor Compression ◽  
Technical Data ◽  
Design And Optimization ◽  
The Mean ◽  
Analysis Design ◽  
Phenomenological Coefficients ◽  
Condensing Pressure

Dynamic process modeling by the mean of Equivalent Gibbs systems is described here. It allows to model a large number of processes and only requires standard engineering knowledge. This method is issued from thermodynamics of irreversible processes, initiated by I. Prigogine, but applied here to process engineering. First, an Equivalent Gibbs System (EGS) is defined for each component involved in the process. In such system, mass, energy and entropy are linked through Gibbs equation and entropy production can easily be expressed according to fluxes and their related forces. Assuming linear phenomenological laws, phenomenological coefficients can be calculated from common engineering correlations, or evaluated from technical data if available. As an example, a conventional vapor compression chiller is simulated. Three control modes are analyzed on an exergy basis: on/off control with constant or floating condensing pressure, PID control with variable compressor speed.

scholarly journals Impact of detector simulation in particle physics collider experiments - highlights

2019 ◽  
Vol 214 ◽  
pp. 02019
Author(s):  
V. Daniel Elvira
Keyword(s):  
Particle Physics ◽  
High Energy Physics ◽  
Hadron Collider ◽  
High Energy ◽  
Design And Optimization ◽  
The Cost ◽  
Detector Simulation ◽  
The Impact ◽  
Journal Submission ◽  
Energy Physics

Detector simulation has become fundamental to the success of modern high-energy physics (HEP) experiments. For example, the Geant4-based simulation applications developed by the ATLAS and CMS experiments played a major role for them to produce physics measurements of unprecedented quality and precision with faster turnaround, from data taking to journal submission, than any previous hadron collider experiment. The material presented here contains highlights of a recent review on the impact of detector simulation in particle physics collider experiments published in Ref. [1]. It includes examples of applications to detector design and optimization, software development and testing of computing infrastructure, and modeling of physics objects and their kinematics. The cost and economic impact of simulation in the CMS experiment is also presented. A discussion on future detector simulation needs, challenges and potential solutions to address them is included at the end.

scholarly journals A Fast and Accurate Method for Computing the Microwave Heating of Moving Objects

2020 ◽  
Vol 10 (8) ◽  
pp. 2985
Author(s):  
Min Zhang ◽  
Xiubo Jia ◽  
Zhixiang Tang ◽  
Yixuan Zeng ◽  
Xuejiao Wang ◽  
...  
Keyword(s):  
Microwave Heating ◽  
Moving Objects ◽  
Computing Time ◽  
Accurate Method ◽  
High Energy ◽  
Good Choice ◽  
Heating Process ◽  
Arbitrary Lagrangian Eulerian ◽  
Dielectric Parameters ◽  
Arbitrary Lagrangian Eulerian Method

In this paper, we show a fast and accurate numerical method for simulating the microwave heating of moving objects, which is still a challenge because of its complicated mathematical model simultaneously coupling electromagnetic field, thermal field, and temperature-dependent moving objects. By contrast with most discrete methods whose dielectric parameters of the heated samples are updated only when they move to a new position or even turn a circle, in our simulations a real-time procedure is added to renew the parameters during the whole heating process. Furthermore, to avoid the mesh-mismatch induced by remeshing the moving objects, we move the cavity instead of samples. To verify the efficiency and accuracy, we compared our method with the arbitrary Lagrangian–Eulerian method, one of the most accurate methods for computing this process until now. For the same computation model, our method helps in decreasing the computing time by about 90% with almost the same accuracy. Moreover, the influence of the rotational speed on the microwave heating is systematically investigated by using this method. The results show the widely used speed in domestic microwave ovens, 5 rpm, is indeed a good choice for improving the temperature uniformity with high energy efficiency.

scholarly journals Timing Performance Simulation for 3D 4H-SiC Detector

Micromachines ◽  
2021 ◽  
Vol 13 (1) ◽  
pp. 46
Author(s):  
Yuhang Tan ◽  
Tao Yang ◽  
Kai Liu ◽  
Congcong Wang ◽  
Xiyuan Zhang ◽  
...  
Keyword(s):  
Time Resolution ◽  
High Energy Physics ◽  
3D Structure ◽  
Three Dimensional ◽  
Threshold Energy ◽  
Atomic Displacement ◽  
High Energy ◽  
Simulation Software ◽  
Design And Optimization ◽  
Displacement Threshold

To meet the high radiation challenge for detectors in future high-energy physics, a novel 3D 4H-SiC detector was investigated. Three-dimensional 4H-SiC detectors could potentially operate in a harsh radiation and room-temperature environment because of its high thermal conductivity and high atomic displacement threshold energy. Its 3D structure, which decouples the thickness and the distance between electrodes, further improves the timing performance and the radiation hardness of the detector. We developed a simulation software—RASER (RAdiation SEmiconductoR)—to simulate the time resolution of planar and 3D 4H-SiC detectors with different parameters and structures, and the reliability of the software was verified by comparing the simulated and measured time-resolution results of the same detector. The rough time resolution of the 3D 4H-SiC detector was estimated, and the simulation parameters could be used as guideline to 3D 4H-SiC detector design and optimization.

scholarly journals Chrononutrition during Pregnancy: A Review on Maternal Night-Time Eating

Nutrients ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 2783
Author(s):  
See Ling Loy ◽  
Rachael Si Xuan Loo ◽  
Keith M. Godfrey ◽  
Yap-Seng Chong ◽  
Lynette Pei-Chi Shek ◽  
...  
Keyword(s):  
Pregnancy Outcomes ◽  
High Energy ◽  
Lifestyle Behaviors ◽  
Contributing Factors ◽  
Night Time ◽  
Cross Sectional ◽  
Night Eating ◽  
Nutritional Characteristics ◽  
Different Populations ◽  
Offspring Health

Evidence from women working night shifts during pregnancy indicates that circadian rhythm disruption has the potential to adversely influence pregnancy outcomes. In the general population, chronodisruption with the potential to affect pregnancy outcomes may also be seen in those with high energy intakes in the evening or at night. However, maternal night eating during pregnancy remains understudied. This narrative review provides an overview of the prevalence, contributing factors, nutritional aspects and health implications of night eating during pregnancy. We derived evidence based on cross-sectional studies and longitudinal cohorts. Overall, night eating is common during pregnancy, with the estimated prevalence in different populations ranging from 15% to 45%. The modern lifestyle and the presence of pregnancy symptoms contribute to night eating during pregnancy, which is likely to coexist and may interact with multiple undesirable lifestyle behaviors. Unfavorable nutritional characteristics associated with night eating have the potential to induce aberrant circadian rhythms in pregnant women, resulting in adverse metabolic and pregnancy outcomes. More research, particularly intervention studies, are needed to provide more definite information on the implications of night eating for mother-offspring health.

Selective Emitters Design and Optimization for Energy Harvesting Using Rectennas

2016 ◽  
Author(s):  
Mehdi Zeyghami ◽  
Philip D. Myers ◽  
D. Yogi Goswami ◽  
Elias Stefanakos
Keyword(s):  
High Efficiency ◽  
Characteristic Length ◽  
High Energy ◽  
Algorithm Optimization ◽  
Selective Emitter ◽  
Design And Optimization ◽  
Attractive Option ◽  
Conversion Efficiencies ◽  
Thermal Sources ◽  
Selective Emitters

Recently, rectennas have drawn attention as an attractive option to harvest radiative thermal energy from the sun and terrestrial thermal sources. In order to achieve the potential high energy conversion efficiencies by this technology, matching conditions between the incident electromagnetic wavelength and the rectenna characteristic length must be satisfied. Therefore, a selective emitter is a key element in high efficiency rectennas. Photonic structures were designed for selective emission using the transfer matrix method and genetic algorithm optimization. Two types of emitters were developed using aluminum as the supporting substrate. This paper presents narrowband selective emitters with a peak emissivity at 9.45 μm made of alternating layers of Al2O3 and SiO2 on a substrate, and broadband selective emitters made of alternating layers of Al2O3 and SiC on a substrate with a high emissivity band between 9.5 μm and 10.5 μm.

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