Related Experiment Video
Updated: Jul 2, 2026
11:11
Experimental Methods for Investigation of Shape Memory Based Elastocaloric Cooling Processes and Model Validation
Published on: May 2, 2016
Temperature-dependent thermal diffusivity of cupuassu pulp: Mathematical modeling and experimental validation
Jhony T Teleken1, Brenda Sm Barboza1, Suélen M de Amorim1
1Faculty of Chemical Engineering, Federal University of Southern and Southeastern Pará, Marabá, PA, Brazil.
Summary
This study determined the thermal diffusivity of cupuassu pulp using an inverse method. A power-law model accurately predicted heat transfer during thermal processing, crucial for food engineering.
Area of Science:
- Food Science and Technology
- Thermodynamics
- Heat Transfer Engineering
Background:
- Cupuassu (Theobroma grandiflorum) pulp is a valuable Amazonian product.
- Understanding its thermophysical properties, especially thermal diffusivity, is key for effective heat treatment design.
Purpose of the Study:
- To determine the thermal diffusivity of cupuassu pulp using experimental data and an inverse method.
- To evaluate different models for temperature-dependent thermal diffusivity.
Main Methods:
- Heating cupuassu pulp in an aluminum capsule and measuring central temperature.
- Employing a 2D transient heat conduction model with Dirichlet boundary conditions.
- Estimating thermal diffusivity (α) via finite difference method and RMSE minimization.
- Iteratively updating α and comparing constant, square-root, linear, and power-law models.
Main Results:
- Temperature-dependent models significantly improved predictive performance.
- The power-law model, α(T) = A + BT^(3/2), provided the best fit with RMSE ≈ 0.1°C.
- The derived α model demonstrated robustness through validation with independent datasets.
Conclusions:
- The power-law model accurately describes the temperature dependence of cupuassu pulp's thermal diffusivity.
- This finding is essential for optimizing thermal processing and ensuring quality in cupuassu-based products.
Related Concept Videos
01:12Heat Flow and Specific Heat
Heat is a type of energy transfer that is caused by a temperature difference, and it can change the temperature of an object. Since heat is a form of energy, its SI unit is the joule (J). Another common unit of energy often used for heat is the calorie (cal), which is defined as the energy needed to change the temperature of 1 g of water by 1 °C, specifically between 14.5 °C and 15.5 °C, since the energy needed shows a slight temperature dependence. Another commonly used unit is the kilocalorie...
01:27Thermal expansion and Thermal stress: Problem Solving
San Francisco's Golden Gate Bridge is exposed to temperatures ranging from -15 °C to 40 °C. At its coldest, the main span of the bridge is 1275 m long. Assuming that the bridge is made entirely of steel, what is the change in its length between these temperatures?
To solve the problem, first, identify the known and unknown quantities. The initial length (L) of the bridge is 1275 m, the coefficient of linear expansion (α) for steel is 12 x 10-6/°C, and the change in temperature (ΔT) is 55 °C.
To solve the problem, first, identify the known and unknown quantities. The initial length (L) of the bridge is 1275 m, the coefficient of linear expansion (α) for steel is 12 x 10-6/°C, and the change in temperature (ΔT) is 55 °C.
01:24Thermodynamics: Activity Coefficient
Activity is the measure of the effective concentration of the species in solution. It can be expressed as the product of the molar concentration of the species and its activity coefficient. The activity coefficient is a dimensionless quantity and depends on the total ionic strength of the solution.
The activity coefficient is a measure of the deviation from ideal behavior. When the ionic strength of the solution is minimal, the activity coefficient of an ionic species is close to unity, making...
The activity coefficient is a measure of the deviation from ideal behavior. When the ionic strength of the solution is minimal, the activity coefficient of an ionic species is close to unity, making...
01:16Specific Heat
The specific heat capacity of a substance refers to the energy required to increase the temperature of one gram of that substance by one degree Celcius. Specific heat capacity is often represented in calories (cal), grams (g), and degrees Celsius (oC), but can also be expressed in joules (J), kilograms (kg), and Kelvin (K), among other units.
For example, increasing the temperature of one gram of water by 1°C requires one calorie of heat energy and can be written as 1 cal/g-°C, or 4186 J/kg/K.
For example, increasing the temperature of one gram of water by 1°C requires one calorie of heat energy and can be written as 1 cal/g-°C, or 4186 J/kg/K.
02:45Responses to Heat and Cold Stress
Every organism has an optimum temperature range within which healthy growth and physiological functioning can occur. At the ends of this range, there will be a minimum and maximum temperature that interrupt biological processes.
01:21Joule-Thomson Effect
The Joule-Thomson effect, also known as the Joule-Kelvin effect, describes the temperature change of a fluid when it is forced through a valve or porous plug while keeping it in a thermally insulated environment. This experiment is called a throttling process. This is an important effect widely used in refrigeration and the liquefaction of gases.
This experiment forces high-pressure gas through a throttle valve or a porous plug to a lower-pressure region. The gas expands as it passes through to...
This experiment forces high-pressure gas through a throttle valve or a porous plug to a lower-pressure region. The gas expands as it passes through to...