A cost-effective method to improve the performance of solar air heaters using discrete macro-encapsulated PCM capsules for drying applications. (5th January 2019)

• Record Type: Journal Article
• Authors: Raj, A.K.; Srinivas, M.; Jayaraj, S.
• Is Part Of: Applied thermal engineering. Volume 146(2019)
• Page Start: 910
• Page End: 920
• Publication Date: 2019-01-05
• Subjects: Cost analysis -- Macro-encapsulation -- Organic PCM -- Solar air heaters; Heat engineering -- Periodicals; Heating -- Equipment and supplies -- Periodicals; Periodicals; 621.40205
• DOI: 10.1016/j.applthermaleng.2018.10.055
• Languages: English
• ISSNs: 1359-4311

Abstract

Highlights: PCM in metallic macro-encapsulate inside DPSAHS was investigated. Rectangular and cylindrical metallic macro-encapsulate was tested. Energy and cost analysis of DPSAHS with and without storage was conducted. An average encapsulate efficiency of 47.2% and 67% was obtained. Cost of heating 1 kg of hot air was $0.0074. Abstract: The present experimental work attempts to sustain the thermal response of the double-pass solar air heater system (DPSAHS) by the thermal lag of phase change material (PCM). At the same time, this analysis investigates the role of metallic macro-encapsulation on the heat storage and recovery from PCM integrated inside the DPASHS. The objectives are to investigate the influence of the geometry of encapsulation used for storage and to examine whether the discrete units allow faster charging and discharging of organic paraffin wax (PCM). In this work, an average encapsulate efficiency of 47.2% and 67% was obtained respectively for rectangular and cylindrical macro-encapsulates equipped DPSAHS. A performance comparison of DPSAHS with and without storage was presented. An overall cost analysis shows that with a small margin in constructional cost, operational time of DPSAHS was improved. The cost of heating 1 kg of hot air was 0.0074$. The overall work aims to support marginal and subsistent farmers to deal with improper drying during winter on which the potential sunshine hours are limited to 7 h/day at Calicut (11 o 32 ' N, 75 o 93 ' E) located in peninsular India.