Abstract Geophysical sensing in the open ocean is both costly and technically challenging. Here we developed a novel distributed fiber optic sensing technique that employs microwave modulation for phase measurement in signals returned from submarine repeaters. We transformed a trans‐Atlantic telecom cable into an 81‐sensor array and measured sub‐millihertz strains. The strains correlate with ocean tide height variations in phase, suggesting a dominant factor of the cable's Poisson's effect. Large strains observed at fiber spans located in the shallow water match the strong variations of simulated seafloor temperature. This study presents the first experimental confirmation of detecting sub‐millihertz signals using trans‐oceanic distributed sensing with submarine cables at span‐wise spatial resolution (∼80 km), opening the potential for cost‐efficient tsunami early warning and long‐term ocean temperature monitoring compatible with active data‐carrying fibers.
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MVDC Bipolar Power Cables with Rectangular Geometry Design for Envisaged All-Electric Wide-Body Aircraft
Designing power cables that provide high power and low system mass is one of the major goals in achieving the future all-electric wide-body aircraft. Radiative and convective heat transfers from a cable's surface to the surrounding air determine how much current is permitted to flow through it. At a cruising altitude of 12.2 km (18.8 kPa) for wide-body aircraft, the limited heat transfer by convection poses thermal issues for the design of aircraft cables. These thermal challenges are exacerbated for bipolar electric power systems (EPS), which are usually made up of two power lines next to each other. The cable's surface area affects both convective and radiative heat transfers. Changing the shape of the cable is one technique to improve heat transfers and compensate for the reduced convective heat transfer caused by low air pressure. In comparison to cylindrical and cuboid cables, the rectangular geometry design gives a bigger contact area with the surrounding atmosphere for the same cross-section area, hence it is anticipated that the heat transfer would rise and as a result, the cable's maximum power-carrying capability will be higher. The purpose of this paper is to design ±5 kV bipolar MVDC power cables with rectangular geometry to raise the maximum current carrying capacity of the cable and analyze its performance with bipolar cylindrical and cuboid geometries.
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- Award ID(s):
- 2306093
- PAR ID:
- 10498699
- Publisher / Repository:
- IEEE
- Date Published:
- Journal Name:
- 2024 IEEE Texas Power and Energy Conference (TPEC)
- ISBN:
- 979-8-3503-3120-2
- Page Range / eLocation ID:
- 1 to 5
- Format(s):
- Medium: X
- Location:
- College Station, TX, USA
- Sponsoring Org:
- National Science Foundation
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