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An Effective Flux Framework for Linear Irreversible Heat Engines: Case Study of a Thermoelectric Generator
Jasleen Kaur1, Ramandeep S Johal1
1Department of Physical Sciences, Indian Institute of Science Education and Research Mohali, Sector 81 SAS Nagar, Manauli 140306, Punjab, India.
Entropy (Basel, Switzerland)
|March 28, 2024
Summary
This study models an autonomous heat engine using linear irreversible thermodynamics. It simplifies entropy generation into a single thermal flux, applicable to thermoelectric generators with internal and external irreversibilities.
Area of Science:
- Thermodynamics
- Non-equilibrium systems
- Energy conversion
Background:
- Autonomous heat engines operate between hot and cold reservoirs.
- Linear irreversible thermodynamics provides a framework for analyzing such systems.
- Entropy generation is a key metric for efficiency in heat engines.
Purpose of the Study:
- To model an autonomous heat engine within a linear irreversible framework.
- To simplify the rate of entropy generation.
- To analyze scenarios with internal and external irreversibilities.
Main Methods:
- Utilizing a tight-coupling approximation.
- Expressing entropy generation in terms of a single effective thermal flux.
- Deriving algebraic forms for the effective flux.
Main Results:
- The rate of entropy generation is shown to be a homogeneous function of hot and cold fluxes.
- Specific algebraic forms of the effective flux were deduced.
- The model is applied to a thermoelectric generator.
Conclusions:
- The tight-coupling approximation effectively simplifies entropy generation analysis.
- The derived effective flux provides insights into heat engine performance under irreversibilities.
- The findings are relevant for optimizing thermoelectric generator efficiency.
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