Related Concept Videos
01:07Refrigerators and Heat Pumps
Refrigerators or heat pumps are heat engines operating in a reverse direction. For a refrigerator, the focus is on removing heat from a specific area, whereas, for a heat pump, the focus is on dumping heat into one particular area. A refrigerator (or heat pump) absorbs heat Qc from the cold reservoir at Kelvin temperature Tc and discards heat Qh to the hot reservoir at Kelvin temperature Th, while work W is done on the engine’s working substance.
A household refrigerator removes heat from the...
A household refrigerator removes heat from the...
01:14Mechanisms of Heat Transfer I
Just as interesting as the effects of heat transfer on a system are the methods by which the heat transfer occur. Whenever there is a temperature difference, heat transfer occurs. It may occur rapidly, such as through a cooking pan, or slowly, such as through the walls of a picnic ice box. So many processes involve heat transfer that it is hard to imagine a situation where no heat transfer occurs. Yet, every heat transfer takes place by only three methods: conduction, convection, and radiation.
01:20Mechanisms of Heat Transfer II
In convection, thermal energy is carried by the large-scale flow of matter. Ocean currents and large-scale atmospheric circulation, which result from the buoyancy of warm air and water, transfer hot air from the tropics toward the poles and cold air from the poles toward the tropics. The Earth’s rotation interacts with those flows, causing the observed eastward flow of air in the temperate zones. Convection dominates heat transfer by air, and the amount of available space for the airflow...
01:14Mechanisms of Heat Transfer
Heat transfer between the human body and its environment occurs through four main mechanisms: conduction, convection, radiation, and evaporation.
Conduction, accounting for approximately 3% of body heat loss at rest, is the process of exchanging heat between molecules of two materials in direct contact. This can result in both heat loss and gain. For instance, when the body is submerged in water, which conducts heat 20 times more effectively than air, it can either lose or gain significant heat.
Conduction, accounting for approximately 3% of body heat loss at rest, is the process of exchanging heat between molecules of two materials in direct contact. This can result in both heat loss and gain. For instance, when the body is submerged in water, which conducts heat 20 times more effectively than air, it can either lose or gain significant heat.
01:19Mechanism of heat transfer
Understanding heat transfer mechanisms is essential for understanding how our bodies maintain balance in different environmental conditions. When the environment is thermoneutral, the body is in a state of balance, neither using nor releasing energy to maintain its core temperature. However, when the environment is not thermoneutral, the body employs four heat transfer mechanisms to maintain homeostasis: conduction, convection, evaporation, and radiation. These mechanisms facilitate heat...
01:14Heat Capacities of an Ideal Gas I
Heat capacity is the ratio of heat absorbed by the substance corresponding to its temperature change. It is also called thermal capacity and the SI unit of heat capacity is J/K. Whereas, specific heat capacity is defined as the amount of heat necessary to change the temperature of 1 kg of a substance by 1 K and is also called massic heat capacity. Its SI unit is J/kg⋅K.
Molar heat capacity quantifies the ratio of the amount of heat added (or removed) to increase (or decrease) the temperature of...
Molar heat capacity quantifies the ratio of the amount of heat added (or removed) to increase (or decrease) the temperature of...
You might also read
Related Articles
Articles linked to this work by shared authors, journal, and citation graph.
Sort by
Same author
Quantized two terminal conductance, edge states and current patterns in an open geometry 2-dimensional Chern insulator.
Journal of physics. Condensed matter : an Institute of Physics journal·2025
Same author
Generalized Hydrodynamic Description of the Page Curve-like Dynamics of a Freely Expanding Fermionic Gas.
Physical review letters·2024
Related Experiment Video
Updated: Jul 15, 2026
09:04
A Modeling and Simulation Method for Preliminary Design of an Electro-Variable Displacement Pump
Published on: June 1, 2022
Two simple models of classical heat pumps.
Rahul Marathe1, A M Jayannavar, Abhishek Dhar
1Raman Research Institute, Bangalore 560080, India.
Summary
This study explores classical models for heat pumping, finding one system can pump heat while a similar system cannot, despite lacking particle transport.
Area of Science:
- Thermodynamics
- Statistical Mechanics
- Classical Physics
Background:
- Recent studies explored quantum heat pumps.
- Classical models offer simpler analysis.
- Ratchet models often involve particle transport.
Purpose of the Study:
- Investigate heat pumping in simple classical models.
- Examine systems without particle transport.
- Compare two distinct classical models.
Main Methods:
- Studied a two-spin system and a coupled oscillator system.
- Systems exchanged heat with multiple reservoirs.
- Applied periodic forces and analyzed results using exact and numerical solutions.
Main Results:
- Demonstrated that one classical model functions as a heat pump.
- Showed a similar classical model does not.
- Confirmed absence of particle transport in both models.
Conclusions:
- Classical models can exhibit heat pumping without particle transport.
- Model design dictates heat pumping capability.
- Distinguishes functional heat pumps from non-functional ones based on underlying principles.