Double diffusion convection plays a significant role in upwelling of nutrients and vertical transport of heat and salt in oceans. Salt fingering contributes to vertical mixing in the oceans. Such mixing helps regulate the gradual overturning circulation of the ocean, which control the climate of the earth.
Double diffusive mixed convection can also play a role in the exploitation of geothermal energy. For example, it can occur in geothermal reservoirs, leading to the mixing of hot and cold fluids and affecting the overall efficiency of energy extraction.
For example, this study
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