Submarine Buoyancy
Submarine Buoyancy - Related Videos
11:30
Buoyancy and Drag on Immersed Bodies
0 Views •
2023
Source: Alexander S Rattner and Sanjay Adhikari; Department of Mechanical and Nuclear Engineering, The Pennsylvania State University, University Park, PA Objects, vehicles, and organisms immersed in fluid mediums experience forces from the surrounding fluid in the form of buoyancy- a vertical upward force due to fluid weight, drag- a resistive force opposite the direction of motion, and lift- a force perpendicular to the direction of motion. Prediction and characterization of these forces is...
01:12
Buoyancy
0 Views •
2025
When an object is placed in a fluid, it either floats or sinks. All objects in a fluid experience a buoyant force. For example, a metal ball sinks, while a rubber ball floats. Similarly, a submarine can sink and float by adjusting its buoyancy. The concept of buoyancy raises several interesting questions. For instance, where does this buoyant force come from? How much buoyant force is required to make an object sink or float? Do objects that sink get any support at all from the fluid? To get...
03:18
Flotation-Based T Cell Isolation Using Buoyancy-Activated Cell Sorting
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2025
This video demonstrates T cell isolation from peripheral blood mononuclear cells (PBMCs) using the functionalized buoyancy-activated cell sorting (BACS) technology. The isolation technique involves the positive selection of CD3+ T cells by labeling the cells with biotinylated anti-CD3 antibodies and separating the antibody-bound cells using streptavidin-bound microbubbles.
08:43
Separation of Uranium and Thorium for 230Th-U Dating of Submarine Hydrothermal Sulfides
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Cited by 2 •
2019
The protocol describes a method to purify and separate the U and Th nuclide in submarine hydrothermal sulfide sample with Fe co-precipitation and extraction chromatography for 230Th-U disequilibrium dating.
08:00
A Buoyancy-based Method of Determining Fat Levels in Drosophila
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Cited by 19 •
2016
Here we present a method to measure organismal fat levels in the third instar (L3) larval stage of Drosophila melanogaster. This method exploits the comparatively low density of fat tissue to differentiate between larvae with altered fat stores. Buoyancy-based analysis is a valuable tool for rapid, reproducible, and economical screening.
FAQs
Ballast tanks change a submarine’s average density by controlling how much seawater and air they contain. Flooding allows seawater to replace air, increasing the vessel’s average density and promoting descent. Blowing the tanks with compressed air expels water, lowering average density and promoting ascent. This adjustment changes the balance between weight and buoyant force while the surrounding seawater provides the displaced fluid.
Neutral buoyancy lets a submarine remain suspended at a chosen depth rather than continually counteracting a tendency to rise or sink. The trim system redistributes water within the vessel to refine this condition after larger ballast changes. Maintaining the balance reduces the propulsion needed for depth control, making underwater movement more controlled and efficient.
The outcome depends on comparing the submarine’s weight with the upward force associated with the water it displaces. Ballast changes the vessel’s average density, while the surrounding water supplies the displaced volume involved in the buoyant response. Considering these quantities together explains why replacing air with seawater favors descent and replacing seawater with compressed air favors ascent.
During descent, seawater is admitted into ballast tanks, replacing air and shifting the vessel toward greater average density. During ascent, compressed air expels that water, shifting the balance in the opposite direction. Trim adjustments then refine the vessel’s condition so it can remain at a selected depth instead of continuing to change depth.
Buoyancy control changes the vessel’s tendency to rise, sink, or stay suspended by adjusting ballast and trim. Propulsion is not the primary adjustment described for establishing that balance; a properly trimmed submarine can maintain depth with minimal propulsion. This distinction connects fluid displacement and force balance to practical underwater navigation.
It provides a practical application of Archimedes’ principle and links force, density, pressure, and fluid displacement in one system. The same understanding supports underwater navigation, vehicle design, and marine research. Studying the vessel’s response to ballast and trim changes also shows how physical principles guide controlled operation in water.