Critical shear stress of sunken, No. 6 heavy fuel oil in fresh water
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View abstract on PubMed
Summary
This summary is machine-generated.Sunken oil transport is initiated when current-induced bed shear stress surpasses the oil's critical shear stress (CSS). This study quanties thresholds for oil movement based on viscosity and sediment size.
Area Of Science
- Environmental Science
- Geology
- Fluid Dynamics
Background
- Sunken oil poses significant environmental risks.
- Understanding oil transport mechanisms is crucial for effective remediation.
- No. 6 heavy fuel oil mixed with kaolinite clay was used to simulate sunken oil conditions.
Purpose Of The Study
- To define and quantify the thresholds of sunken oil transport.
- To evaluate the critical shear stress (CSS) of oil as a function of environmental and oil properties.
- To develop empirical relationships for predicting oil CSS during transport.
Main Methods
- Flume and laboratory experiments were conducted.
- Thresholds for oil movement were determined by measuring current-induced bed shear stress.
- Oil's critical shear stress was analyzed in relation to water velocity, temperature, oil condition, and sediment size.
Main Results
- Multiple stages of oil transport were identified for lower kinematic viscosity (v<sub>o</sub><2 × 10<sup>4</sup> cSt): gravity dispersion, rope formation, ripple formation, and break-apart/resuspension.
- For higher kinematic viscosity (v<sub>o</sub>> 6 × 10<sup>4</sup> cSt), oil transport occurred as a single intact saltating event.
- Empirical relationships were developed to predict oil CSS based on kinematic viscosity and sediment size.
Conclusions
- The critical shear stress (CSS) is a key parameter for understanding sunken oil mobility.
- Oil transport behavior is dependent on its kinematic viscosity and the surrounding sediment characteristics.
- The developed empirical relationships can aid in predicting and managing sunken oil transport events.
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