The optimization of tank-volume-to-collector-area ratio for a thermosyphon solar water heater

doi:10.1016/0960-1481(95)00132-8

Renewable Energy

Volume 7, Issue 3, March 1996, Pages 289-300

https://doi.org/10.1016/0960-1481(95)00132-8 Get rights and content

Abstract

Through the use of the TRNSYS simulation program, the performance of a domestic solar water heating system operating with natural circulation (thermosyphon) and a daily hot water load has been analysed. The effect of tank height on the annual solar fraction of the system has been investigated for different hot water load temperatures and storage tank volumes. Optimum values (values which maximize the annual solar fraction of the system) for storage tank height and volume are calculated for operating temperatures ranging from 50 to 80°C. The response of the system to the ratio of the storage tank volume to the collector area is investigated. The dependence of the solar fraction on tank height was observed to be more notable in the case of large tank volumes and high load temperatures. The results indicate the existence of an optimum value for the tank volume at a given tank height and a high load temperature. At lower temperatures, the solar fraction rises rapidly with tank volume to a nearly constant level. An optimum value of the storage-tank-volume-to-collector-area ratio was also observed at high load temperatures.

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Citation Excerpt :
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ArticleThe optimization of tank-volume-to-collector-area ratio for a thermosyphon solar water heater

Abstract

Solar Energy

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System design in solar water heaters with natural circulation

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A finite difference method to evaluate the thermal performance of a solar water heater

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Performance characteristics of a thermosyphon solar domestic hot water system

ASME J. Solar Energy Engng

Detailed loop model (DLM) analysis of liquid solar thermosiphons with heat exchangers

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Article
The optimization of tank-volume-to-collector-area ratio for a thermosyphon solar water heater