Journal Press India^®

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Solar liquid collectors are good candidate of heat transfer enhancement. The efficiency of a solar liquid collector can be improved by augmenting tube side heat transfer using enhanced techniques used in heat exchangers. Various types of heat transfer enhancement techniques has been used in heat exchangers which are mainly classified in two types, active and passive techniques. Solar liquid collectors can also be enhanced by these active and passive devices. Passive techniques, mainly swirl flow devices are more popular enhancement techniques in solar liquid collectors as they do not require any external source of power and also they do not affect the mechanical strength of tube material. Initially twisted tape inserts and conical inserts were popular passive devices used in enhanced solar liquid collectors mainly because of availability of established correlations. Wire coil inserts are relatively less experimented passive technique. This study is focused on tube side heat transfer augmentation of a solar flat plate liquid collector by wire coil inserts and effect of various dimensionless parameters on thermal efficiency of solar collector.

Keywords

Solar collectors; solar flat plate liquid collectors; heat transfer enhancement; twisted tape; coiled wire.

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