Name: heat transfer calculations with conduction, convection
Uploaded: 2023-09-18T17:11:17.000Z
Duration: 1 min 20 s
Channel: JoVE

K12 Standards

north-carolina-k-12-science-standard-course-of-study

NC K-12 Science Standard Course of Study

9-12

Physical Science

Energy

PS.PSc.7.1

conduction-convection-and-radiation-problem-solving

Conduction, Convection and Radiation: Problem Solving

Un muro de 13 cm de espesor con una superficie de 100m2 y una conductividad térmica de 1,5 W/mK separa una habitación de la atmósfera exterior, que se encuentra a 3 grados centígrados.
La superficie exterior de la pared está a 10 grados centígrados y su emisividad es de 0,8. Si el coeficiente de transferencia de calor convectivo es de 15 W/m2K , encuentre la tasa total de pérdida de calor en el entorno. Además, calcule la temperatura de la superficie interna de la pared.
Aquí, los tres mecanismos de transferencia de calor están involucrados. El calor se transfiere de la superficie interior a la exterior de la pared a través de la conducción, mientras que la pérdida de calor al entorno se produce debido a la convección y la radiación.
La tasa de pérdida de calor por convección depende del gradiente de temperatura, el área de superficie y el coeficiente de transferencia de calor.
Por lo tanto, la pérdida total de calor en el entorno debido a la convección y la radiación se puede calcular como 13,27 x 103 W.
Empleando la conservación de energía y sustituyendo los términos en la ecuación del calor, se puede calcular la temperatura de la superficie interna de la pared.

<ol>
	<li>OpenStax. (2019). Física Universitaria Vol. 2. [Versión web]. Obtenido de <a href="https://openstax.org/books/university-physics-volume-2/pages/1-6-mechanisms-of-heat-transfer">https://openstax.org/books/university-physics-volume-2/pages/1-6-mechanisms-of-heat-transfer</a></li>
</ol>

conducción, convección y radiación: resolución de problemas

Hay tres métodos mediante los cuales puede tener lugar la transferencia de calor: conducción, convección y radiación. Cada método tiene características únicas e interesantes, pero los tres tienen dos cosas en común: transfieren calor únicamente debido a una diferencia de temperatura; y cuanto mayor sea la diferencia de temperatura, más rápida será la transferencia de calor. Para resolver un problema relacionado con la transferencia de calor, primero se debe examinar la situación para determinar el tipo de transferencia de calor involucrada. Esto puede ser conducción, convección, radiación o los tres. El segundo paso es identificar y anotar las magnitudes desconocidas en el problema. Se puede hacer una lista de lo que se da o lo que se puede inferir del problema tal como está planteado, es decir, las magnitudes conocidas, seguido de resolver la ecuación apropiada para la magnitud a determinar. Para la transferencia de calor mediante conducción, se debe usar la siguiente ecuación. <img alt="Equation1" src="/files/ftp_upload/14166/14166_Equation_1.svg" style="text-align: center; height: 46px;"> Para la convección, la tasa de pérdida de calor depende del gradiente de temperatura, el área de superficie y el coeficiente de transferencia de calor. <img alt="Equation2" src="/files/ftp_upload/14166/14166_Equation_2.svg" style="text-align: center; height: 18px;"> La siguiente ecuación da la tasa neta de transferencia de calor por radiación. <img alt="Equation3" src="/files/ftp_upload/14166/14166_Equation_3.svg" style="text-align: center; height: 25px;"> Sustituyendo las magnitudes conocidas junto con sus unidades en la ecuación apropiada y resolviéndola numéricamente se obtiene la solución correcta.

Conducción, Convección y Radiación: Resolución de Problemas

Hay tres métodos por los cuales se puede realizar la transferencia de calor: conducción, convección y radiación. Cada método tiene características únicas e interesantes ...

Education

Educación

JoVE Core

Physics

Física

Unit 1

Unidad 1

Temperature and Heat

Temperatura y calor

KEY TERMS AND CONCEPTS

TÉRMINOS Y CONCEPTOS CLAVE

heat transfer calculations with conduction, convection

Heat transfer calculations with conduction and convection use the temperature difference to find the rate of heat flow. Radiation can also be part of the process. The main idea is that heat moves only because one area is hotter than another, and a larger temperature difference leads to faster transfer.

To solve a heat transfer problem, first identify the type of transfer involved. It may be conduction, convection, radiation, or a combination of all three. Next, write down the unknown quantities and sort the given information from the problem statement.

After the known values are listed, choose the correct equation for the type of heat transfer. Use the conduction equation for heat flow through materials. For convection, the rate of heat loss depends on the temperature gradient, the surface area, and the heat transfer coefficient. For radiation, use the equation for net heat transfer rate.

Finally, substitute the known quantities and their units into the selected equation. Solve the equation numerically to find the answer. This method helps students work through heat transfer problems in a clear, step-by-step way.

Heat Transfer Calculations with Conduction, Convection

heat-transfer-calculations-with-conduction-convection

temperature and thermal equilibrium

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zeroth law of thermodynamics

Thermal Equilibrium and the Zeroth Law

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thermometers and temperature scales

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gas thermometers and the kelvin scale

Kelvin Temperature and Gas Thermometer Standards

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thermal expansion

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thermal stress

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thermal expansion and thermal stress: problem solving

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Convection and radiation are two major ways heat moves. In convection, thermal energy is carried by the large-scale flow of matter. Warm air and water rise because they are less dense, so ocean currents and large-scale atmospheric circulation move heat from the tropics toward the poles and move cold air from the poles toward the tropics. Earth’s rotation changes these moving air currents. It interacts with the flow and helps produce the eastward movement of air in the temperate zones.

conduction, convection and radiation: problem solving

Heat transfer calculations with conduction and convection use the temperature difference to find the rate of heat flow. Radiation can also be part of the process. The main idea is that heat moves only because one area is hotter than another, and a larger temperature difference leads to faster transfer. To solve a heat transfer problem, first identify the type of transfer involved. It may be conduction, convection, radiation, or a combination of all three. Next, write down the unknown...

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key terms and concepts

Learn how to solve heat transfer problems by identifying conduction, convection, or radiation, choosing the right equation, and calculating the unknowns.

Heat Transfer Calculations with Conduction, Convection | JoVE K12

physics

JoVE Core Física presenta la teoría y la aplicación de conceptos físicos fundamentales, como la cinemática, dinámica, mecánica de fluidos, estática, ondas y acústica, mediante animaciones audiovisuales concisas y fáciles de entender. Además, los vídeos de científicos en acción muestran la aplicación de los conceptos relacionados en experimentos de investigación clásicos y originales, realizados en laboratorios de todo el mundo.

Louisiana Student Standards for Science

High School

Chemistry

HS-PS3-3

HS-PS3-4

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Ohio’s Learning Standards and Model Curriculum

Energy And Waves

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Transfer and transformation of energy (including work)

Thermal energy

Tennessee Academic Standards

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PHYS.PS3.2

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PS.5

PS.5.b

Texas Essential Knowledge and Skills

Earth Systems Science

112.49.c.8.

112.49.c.8.A.

Arizona Science Standards

Earth and Space Science

HS+E.E1

HS+E.E1U1.1

HS+Phy.P4

HS+Phy.P4U2.7

HS.P4

HS.P4U1.8

Alabama Course of Study Science

9-12.PS.1.1.b

Earth's Systems

9-12.ESS.2.7

Next Generation Science Standards

Florida Department of Education

SC.912.P.10

SC.912.P.10.4

Chemistry and Physics

IPC.6

IPC.6.D

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New York State Science Learning Standards

Earth and Space Sciences

Earth’s Systems

HS. ESS2-3.

Energy Basics

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Non-conservative Forces

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Conservation of Energy

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Conservation of Energy: Application

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Use mathematics and computational thinking to explain the Law of Conservation of Energy in a mechanical system in terms of kinetic and potential energy.

PS.PSc.7.2

Work

Work is done when energy is transferred from one object to another. In other words, work is when a force acts on something that undergoes a displacement ...

Positive, Negative, and Zero Work

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Work-energy Theorem

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Work and Energy for Variable Forces

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Work Done Over an Inclined Plane

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Work Done by Many Forces

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Work Done by Gravity

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PS.PSc.7.3

Power

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Power Expended by a Constant Force

The relationship between work done and the time taken to do it can be explained using the concept of power. For example, several sprinters in a race may ...

Construct an explanation to infer the relationship between work and power, both quantitatively and qualitatively.

PS.PSc.7.4

Analyze energy transfers and transformations within a mechanical system.

Heat Transfer Calculations with Conduction, Convection

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