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Refrigeración por torsión mediante fibras retorcidas, enrolladas y superenrolladas
Run Wang1, Shaoli Fang2, Yicheng Xiao1
1State Key Laboratory of Medicinal Chemical Biology, College of Pharmacy, Key Laboratory of Functional Polymer Materials, Nankai University, Tianjin 300071, China.
Science (New York, N.Y.)
|October 12, 2019
Resumen
Las fibras retorcidas, como el caucho y la cuerda de pescar, ofrecen una nueva forma de lograr un enfriamiento eficiente a través del estiramiento mecánico. Esta refrigeración basada en torsión presenta una alternativa prometedora a los métodos de enfriamiento tradicionales.
Área de la Ciencia:
- Ciencias de los materiales
- La termodinámica
- Ingeniería mecánica
Sus antecedentes:
- La refrigeración por compresión de vapor tradicional consume mucha energía y es costosa.
- Se necesitan métodos de enfriamiento alternativos tanto para aplicaciones a gran escala como para aplicaciones a pequeña escala.
- Los cambios de entropía en los sólidos durante la deformación mecánica ofrecen potencial para una nueva refrigeración.
Objetivo del estudio:
- Investigar los efectos de enfriamiento del estiramiento mecánico de las fibras retorcidas.
- Explorar el potencial de la refrigeración basada en torsión como alternativa a los sistemas de compresión de vapor.
- Para analizar los mecanismos detrás del enfriamiento mejorado por torsión.
Principales métodos:
- Estiramiento y enrollamiento de varias fibras, incluido el caucho natural, el níquel titanio y la cuerda de pesca de polietileno.
- Utilizando quiralidades opuestas de torsión y enrollamiento para crear fibras superenrolladas.
- Desarrollo y ensayo de un dispositivo basado en torsión para el enfriamiento del agua corriente.
- Ejecutar cálculos mecánicos para comprender las dependencias axiales y del índice de resorte.
Principales resultados:
- Se observaron efectos de enfriamiento elevados debido a cambios de torsión en las fibras estiradas.
- El caucho natural enrollado y las fibras de la línea de pesca enrollada mostraron enfriamiento al estirarse.
- Un dispositivo basado en torsión demostrado logró una alta energía de refrigeración y eficiencia del dispositivo.
- Los cálculos mecánicos aclararon el origen del enfriamiento mejorado por torsión en la transformación de fase para el polietileno.
Conclusiones:
- El enfriamiento por torsión en fibras es un mecanismo de refrigeración viable y eficiente.
- Esta tecnología ofrece una alternativa prometedora, de menor costo y mayor eficiencia a la refrigeración convencional.
- Un análisis mecánico adicional puede optimizar los dispositivos de enfriamiento basados en torsión.
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