Theoretical investigation on inverse identification of spectral properties of paraffin phase change materials based on multi-thickness model. (1st September 2021)

• Record Type: Journal Article
• Authors: Wei, Linyang; Li, Guojun; Song, Miaomiao; Sun, Shuangcheng
• Is Part Of: Solar energy. Volume 225(2021)
• Page Start: 266
• Page End: 274
• Publication Date: 2021-09-01
• Subjects: Paraffin materials -- Spectral properties -- Multi-thickness model -- Solar energy -- Inverse problem; Solar energy -- Periodicals; Solar engines -- Periodicals; 621.47
• DOI: 10.1016/j.solener.2021.07.006
• Languages: English
• ISSNs: 0038-092X

Abstract

Highlights: Spectral refractive index and absorption index of paraffin in solid and liquid are inversed. An multi-thickness model is proposed to overcome ill-posedness of inverse problems. An IQPSO algorithm is adopted as inverse problem solver to obtain spectral properties of paraffin. Abstract: Paraffin as an organic phase change material with high latent heat and stable physical and chemical properties, is widely used as building filling materials to absorb and store solar energy. And the spectral properties of paraffin is crucial to study the phase change characteristics of paraffin materials in absorbing solar energy. Therefore, this work studies theoretically the inverse identification of spectral properties of paraffin phase change materials. A multi-thickness model is developed to determine the optical constants (spectral refractive index and absorption index) of paraffin materials in solid and liquid state based on transmittance data. This model overcomes ill-posed and multiple solution of inverse problems. An improved quantum particle swarm optimization algorithm is adopted to determine spectral refractive index and absorption index of paraffin materials with high accuracy. A serious of numerical experiments are implement to study retrieval problems thoroughly and results show that the inverse strategy we develop is a promising technique to obtain spectral properties of paraffin materials.