Cascades of Velocity and Temperature Fluctuations in Buoyancy-Driven Thermal Turbulence

2006 ◽  
Vol 97 (14) ◽  
Author(s):  
Chao Sun ◽  
Quan Zhou ◽  
Ke-Qing Xia
Keyword(s):  
Temperature Fluctuations ◽  
Thermal Turbulence

Hard thermal turbulence in Antarctic Subglacial Lakes

2020 ◽  
Author(s):  
Martin Siegert ◽  
Louis-Alexandre Couston
Keyword(s):  
Water Depth ◽  
Temperature Fluctuations ◽  
Ice Cover ◽  
Stable Layer ◽  
Convective Turbulence ◽  
Physical Conditions ◽  
Thermal Turbulence ◽  
Melt Water ◽  
Subglacial Lakes ◽  
Geothermal Flux

<p>Over 250 stable and isolated subglacial lakes exist at and close to the ice-sheet center in Antarctica. The physical conditions within subglacial lakes, and the differences between distinct lake settings, are critical to evaluating how and where life may best exist. Here, we demonstrate that upward heating by Earth’s geothermal flux provides efficient stirring of Antarctic subglacial lakes’ water, in a variety of ways related to their water depth, ice overburden and ceiling slope. We show that most lakes are in a regime of hard convective turbulence, enabling efficient mixing of nutrient- and oxygen-enriched top melt-water, which is essential for biome formation. Lakes beneath a thin (about less than 3 km) ice cover and lakes with a thick (more than 3 km) ice cover experience similarly-large velocities, but the latter have significantly larger temperature fluctuations and have a stable layer up to several tens of meters thick adjacent to the ice. We discuss the implications of hydrological conditions on the concentration of particulates in the water column.</p>

Effect of compressible flow on perceived temperature fluctuations measured by moving sensor

AIAA Journal ◽  
1999 ◽  
Vol 37 ◽  
pp. 1609-1616
Author(s):  
George Y. Jumper ◽  
Robert R. Beland ◽  
John R. Roadcap ◽  
Owen R. Cote
Keyword(s):  
Compressible Flow ◽  
Temperature Fluctuations ◽  
Perceived Temperature

NI-SPAN-C Alloy 902

Alloy Digest ◽  
1968 ◽  
Vol 17 (1) ◽  
Keyword(s):  
Fracture Toughness ◽  
Corrosion Resistance ◽  
Cold Work ◽  
Temperature Fluctuations ◽  
Heat Treating ◽  
Chromium Alloy ◽  
Constant Modulus ◽  
Nickel Iron ◽  
Iron Chromium Alloy ◽  
Iron Chromium

Abstract N1-SPAN-C alloy 902 is an age-hardenable, nickel-iron-chromium alloy. Its outstanding characteristic is a controllable thermoelastic coefficient. Proper combination of cold work and thermal treatment can produce an essentially constant modulus of elasticity from -50 F to +150 F. The alloy is especially suitable for many types of precision equipment where elastic members are subject to temperature fluctuations. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties as well as fracture toughness and fatigue. It also includes information on corrosion resistance as well as forming, heat treating, machining, joining, and surface treatment. Filing Code: Fe-32. Producer or source: Huntington Alloy Products Division, An INCO Company.

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