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You searched for subject:(Hybrid Mixture Theory). Showing records 1 – 3 of 3 total matches.

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University of Illinois – Urbana-Champaign

1. Deng, Jie. Modeling microwave heating of apple cylinders using hybrid mixture theory based transport equations coupled with Maxwell's laws of electromagnetism.

Degree: MS, 0037, 2014, University of Illinois – Urbana-Champaign

To develop an efficient microwave drying scheme for apple cylinders, a multiscale mathematical model was developed to predict the moisture and temperature profiles. Two-scale hybrid mixture theory (HMT) based transport equations were utilized to describe the fluid (water & gas phases) transport during the microwave drying of apple cylinders. Maxwell’s electromagnetic equations were coupled with HMT based transport equations to obtain heating source for evaporative moisture loss in the food matrix. A commercial finite element package (COMSOL Multiphysics ver 4.4) was employed to solve these equations in order to obtain the spatial and temporal profiles for moisture and temperature within the sample. The validation experiments were conducted with a domestic microwave oven. The comparison of the moisture profiles obtained through simulations and experiments resulted in an average absolute difference value of 37.9%. For comparison of experimental and predicted temperature values a parametric sweep was performed. The developed model could be employed efficiently for the prediction of the moisture distribution. The temperature change trend could also be predicted using the developed model. Advisors/Committee Members: Takhar, Pawan (advisor).

Subjects/Keywords: Microwave Drying; Hybrid Mixture Theory; Apple Cylinders

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Deng, J. (2014). Modeling microwave heating of apple cylinders using hybrid mixture theory based transport equations coupled with Maxwell's laws of electromagnetism. (Thesis). University of Illinois – Urbana-Champaign. Retrieved from http://hdl.handle.net/2142/50663

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16th Edition):

Deng, Jie. “Modeling microwave heating of apple cylinders using hybrid mixture theory based transport equations coupled with Maxwell's laws of electromagnetism.” 2014. Thesis, University of Illinois – Urbana-Champaign. Accessed October 24, 2019. http://hdl.handle.net/2142/50663.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7th Edition):

Deng, Jie. “Modeling microwave heating of apple cylinders using hybrid mixture theory based transport equations coupled with Maxwell's laws of electromagnetism.” 2014. Web. 24 Oct 2019.

Vancouver:

Deng J. Modeling microwave heating of apple cylinders using hybrid mixture theory based transport equations coupled with Maxwell's laws of electromagnetism. [Internet] [Thesis]. University of Illinois – Urbana-Champaign; 2014. [cited 2019 Oct 24]. Available from: http://hdl.handle.net/2142/50663.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Deng J. Modeling microwave heating of apple cylinders using hybrid mixture theory based transport equations coupled with Maxwell's laws of electromagnetism. [Thesis]. University of Illinois – Urbana-Champaign; 2014. Available from: http://hdl.handle.net/2142/50663

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation


University of Illinois – Urbana-Champaign

2. Bansal, Harkirat. Two-scale modeling of transport mechanisms and quality changes during frying of foods.

Degree: PhD, Food Science & Human Nutrition, 2015, University of Illinois – Urbana-Champaign

Deep fat frying is a popular cooking technique, which involves immersion of foods in edible oil at high temperatures. An excessive fat consumption by humans has been linked to serious health diseases. Frying occurs at temperatures well above the boiling point of water and involves short time duration. Frying results in a rapid change in the quality of the food products. The transport mechanisms along with complex physico-chemical processes such starch gelatinization, protein denaturation, glass transition, phase change, food matrix deformation, etc. that occur during frying govern the final quality of the product. Due to fast paced and dynamic nature of the frying process, it is experimentally challenging to obtain information on transport mechanisms and account for microscale physical phenomena that affect the quality at macroscale. Limited information is available that explains the transport mechanisms during frying and their role in affecting the quality of the product. Hybrid mixture theory (HMT) based multiscale modeling approach was employed to study transport mechanisms during frying of snack foods. Multiscale simulations studies on the frying of rice crackers and chicken nuggets provided useful information about the nature of transport in these two products of different nature. The heat and mass transfer equations were solved using the finite element method to obtain spatial and temporal profiles for moisture and oil content, rate of evaporation, temperature distribution, pore and gas pressures. Average absolute deviation (AAD) for the predicted and the experimental data was calculated for the model validation. Simulations were also used to predict the quality (texture and color) of products during frying. Rice crackers exhibited much higher values of coefficient of elasticity (in the order of 107 Pa) compared to the chicken nuggets (in the order of 105 Pa). Temperature inside a rice cracker reached higher than 100°C in 10 s after the start of the frying process. Whereas, chicken nuggets meat core stayed below 100°C during frying and starch coating experienced temperatures greater than 100°C. The rice crackers exhibited positive values of gage pore pressure for the most part of the frying process. By comparison, pore pressure in the chicken nuggets remained below atmospheric pressure. Existence of negative pore pressure at the start of the frying appeared to be the reason of oil uptake. Kinetics equation for color change obtained from colorimetry experiments was coupled with simulations during post-processing to predict the color (L, a, b) as a function of frying time for chicken nuggets. Lightness value was around 30 for frying at 175°C. Color was more yellow for lower frying temperatures, and redness increased with increasing frying temperature. HMT based model was suitable for simulating the heat and mass transfer mechanisms during frying. Advisors/Committee Members: Takhar, Pawan S (advisor), Lee, Youngsoo (Committee Chair), Schmidt, Shelly J. (committee member), Danao, Mary-Grace (committee member).

Subjects/Keywords: multiscale modeling; Hybrid Mixture Theory; rice crackers; chicken nuggets; oil uptake; heat and mass transfer; Frying

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Bansal, H. (2015). Two-scale modeling of transport mechanisms and quality changes during frying of foods. (Doctoral Dissertation). University of Illinois – Urbana-Champaign. Retrieved from http://hdl.handle.net/2142/78315

Chicago Manual of Style (16th Edition):

Bansal, Harkirat. “Two-scale modeling of transport mechanisms and quality changes during frying of foods.” 2015. Doctoral Dissertation, University of Illinois – Urbana-Champaign. Accessed October 24, 2019. http://hdl.handle.net/2142/78315.

MLA Handbook (7th Edition):

Bansal, Harkirat. “Two-scale modeling of transport mechanisms and quality changes during frying of foods.” 2015. Web. 24 Oct 2019.

Vancouver:

Bansal H. Two-scale modeling of transport mechanisms and quality changes during frying of foods. [Internet] [Doctoral dissertation]. University of Illinois – Urbana-Champaign; 2015. [cited 2019 Oct 24]. Available from: http://hdl.handle.net/2142/78315.

Council of Science Editors:

Bansal H. Two-scale modeling of transport mechanisms and quality changes during frying of foods. [Doctoral Dissertation]. University of Illinois – Urbana-Champaign; 2015. Available from: http://hdl.handle.net/2142/78315


University of Illinois – Urbana-Champaign

3. Dit-U-Dompo, Srivikorn. Multiscale continuum thermodynamics based modeling of transport mechanisms and starch expansion during extrusion.

Degree: PhD, Food Science & Human Nutrition, 2015, University of Illinois – Urbana-Champaign

Expansion is a very critical process that affects the final structural, mechanical and textural characteristics of the extruded products. An understanding of the expansion phenomenon is necessary in order to control and/or improve the functionality of starch products. The hybrid mixture theory based model developed by Takhar (2014) was used to obtain a computer model, which can be used to design, optimize and/or control the process conditions, and improve the specific characteristics of expanded biopolymers. Water, vapor and heat transport mechanisms and thermo–mechanical changes occurring inside the expanding extrudate were described using the two–scale unsaturated transport equations coupled with the poroviscoelasticity equations. The poroviscoelastic extrudate matrix interacted with the fluids (liquid water, vapor and air mixture) contained in its pores. Transport equations were transformed from the moving Eulerian coordinates to the stationary Lagrangian coordinates. Good agreements between the simulated and the experimental values of surface temperature, moisture content and expansion ratio of the extrudates at different extrusion conditions were obtained. Simulations showed the transition from rubbery to glassy state at different spatial locations across the cross–section of the extrudate. The model was also used to predict the temperature, moisture content, and pressure distribution within the extrudate. The extrudate moisture content deceased after exiting from the die due to water evaporation, which resulted in an increase in the glass transition temperature. Therefore, a glassy crust was developed from the surface to interior. An increase in pore pressure of the extrudate caused rapid starch expansion until it reached a maximum. The extrudate stopped expanding when the pore pressure gradient became zero, and collapsed when the pore pressure reduced further to make a negative pressure gradient. The viscoelastic properties also provide an indication about the textural characteristics of starch as a function of extrusion conditions. The viscoelastic properties of extruded cornstarch were measured as a function of process conditions. The extruded cornstarch samples were conditioned in the moisture range of 12.9–31.2% (dry basis). Dynamic and creep behavior of the extrudate were evaluated using a dynamic mechanical analyzer. The storage (G′) and loss moduli (G′′) were determined in the temperature range of 30-100°C and oscillation frequency range of 0.1-51 Hz. The G′ and G″ values showed an increasing trend with a decrease in temperature and moisture content and an increase in frequency. This implied an increase in solid-like behavior when the temperature and moisture content were reduced or the frequency was increased. Rheological parameters based on creep behavior were assessed at 30, 60 and 85°C. Creep data, fitted using Burger’s model, were highly dependent on both moisture content and temperature. The viscoelastic properties obtained in this experimental research were used in the transport model for… Advisors/Committee Members: Takhar, Pawan (advisor), Feng, Hao (Committee Chair), Takhar, Pawan (committee member), Bhalerao, Kaustubh (committee member), Lee, Youngsoo (committee member).

Subjects/Keywords: viscoelastic properties; extruded cornstarch; dynamic properties; creep compliance; expansion ratio; extrusion; poroviscoelasticity; unsaturated transport; multiphase porous media; Hybrid Mixture Theory

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Dit-U-Dompo, S. (2015). Multiscale continuum thermodynamics based modeling of transport mechanisms and starch expansion during extrusion. (Doctoral Dissertation). University of Illinois – Urbana-Champaign. Retrieved from http://hdl.handle.net/2142/78712

Chicago Manual of Style (16th Edition):

Dit-U-Dompo, Srivikorn. “Multiscale continuum thermodynamics based modeling of transport mechanisms and starch expansion during extrusion.” 2015. Doctoral Dissertation, University of Illinois – Urbana-Champaign. Accessed October 24, 2019. http://hdl.handle.net/2142/78712.

MLA Handbook (7th Edition):

Dit-U-Dompo, Srivikorn. “Multiscale continuum thermodynamics based modeling of transport mechanisms and starch expansion during extrusion.” 2015. Web. 24 Oct 2019.

Vancouver:

Dit-U-Dompo S. Multiscale continuum thermodynamics based modeling of transport mechanisms and starch expansion during extrusion. [Internet] [Doctoral dissertation]. University of Illinois – Urbana-Champaign; 2015. [cited 2019 Oct 24]. Available from: http://hdl.handle.net/2142/78712.

Council of Science Editors:

Dit-U-Dompo S. Multiscale continuum thermodynamics based modeling of transport mechanisms and starch expansion during extrusion. [Doctoral Dissertation]. University of Illinois – Urbana-Champaign; 2015. Available from: http://hdl.handle.net/2142/78712

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