Some aspects concerning modelling the flow and heat transfer in horizontal mantle heat exchangers in solar water heaters
✍ Scribed by Gary Rosengarten; Masud Behnia; Graham Morrison
- Publisher
- John Wiley and Sons
- Year
- 1999
- Tongue
- English
- Weight
- 692 KB
- Volume
- 23
- Category
- Article
- ISSN
- 0363-907X
No coin nor oath required. For personal study only.
✦ Synopsis
An experimental and numerical investigation has been undertaken to study the heat transfer process in horizontal mantle heat exchangers used in solar water heaters. A rectangular cavity has been used as a simpli"ed geometry. With the aid of particle image velocimetry (PIV) the #ow "eld in the centre-plane of the rectangular cavity has been visualized. Threedimensional #ow simulations were performed using a commercial CFD package. The impinging jet formed by the inlet #ow directed towards the opposite wall was found to produce localised turbulence in the cavity, with an inlet Reynolds number as low as 360. This turbulence was found to e!ect the #ow "eld and heat transfer in the cavity when the inlet Reynolds number was above 1200. It is shown that, with the boundary conditions used in this study, most of the heat transferred was in the bottom half of the cavity. This is not the ideal situation for optimization of solar water heating systems.