Indexed by:会议论文

Date of Publication:2008-11-16

Included Journals:EI、CPCI-S

Volume:1

Issue:1

Page Number:4969-4976

Key Words:CO2; Droplet/Bubble; Dissolusion; Momentum changes; Modeling

Abstract:A numerical model of an individual CO2 bubble dissolution and ascent in shallow seawater was developed to simulate the fate of CO2 leaked from seabed naturally or artificially. The model consists of a solubility sub-model of CO2 gas in seawater, a CO2 bubble mass transfer sub-model, and a CO2 bubble momentum transfer sub-model. The model is applied to predict the dynamics of leaked CO2 in seawater at various depths from 0-150m (temperature from 10 degrees C to 25 degrees C) and for initial bubble sizes from 3.0 to 40.0mm in diameter. A diagram of CO2 ascending distance vs dissolution time is obtained from model simulations. It is found that CO2 bubbles ascend at a mean speed of 16 cm/sec and a mean shrinking rate of 30x10(-3) mm/s in diameter approximately if leaked from a shallow ocean (<150m) seabed. A parameter, named as critical depth, is defined and suggested as a parameter to indicate if the CO2 leaked from seabed can return to atmosphere. This critical depth is approximately linearly related to the initial bobble size with a gradient of -0.68 m/mm under seawater conditions in the simulation ocean. (C) 2008 Elsevier Ltd. All rights reserved