czas-i-pomiary: Atmospheric entry

Evidence: 100 • authority: 72

Atmospheric entry (sometimes listed as Vimpact or Ventry) is the movement of an object from outer space into and through the gases of an atmosphere of a planet, dwarf planet, or natural satellite. Atmospheric entry may be uncontrolled entry, as in the entry of astronomical objects, space debris, or bolides, or it may be controlled entry (or reentry) of a spacecraft that can be navigated or follow a predetermined course. Methods for controlled atmospheric entry, descent, and landing of spacecraft are collectively termed as EDL. Objects entering an atmosphere experience atmospheric drag, which puts mechanical stress on the object, and aerodynamic heating — caused mostly by compression of the…

Evidence: 43 • authority: 72

In aerodynamics, hypersonic speed refers to speeds much faster than the speed of sound, usually more than approximately Mach 5. The precise Mach number at which a craft can be said to be flying at hypersonic speed varies, since individual physical changes in the airflow (like molecular dissociation and ionization) occur at different speeds; these effects collectively become important around Mach 5–10. The hypersonic regime can also be alternatively defined as speeds where specific heat capacity changes with the temperature of the flow as the kinetic energy of the moving object is converted into heat. Hypersonic weapons are typically boost-glide vehicles or cruise missiles designed for aerod…

Evidence: 37 • authority: 92

Benchmarking CO<sub>2</sub> Adsorbents for Direct Air Capture with an Amine-Grafted Metal-Organic Framework.. Direct air capture (DAC) is a promising strategy for mitigating atmospheric CO 2 accumulation, yet sorbent evaluation remains dominated by equilibrium uptake under static conditions that fail to capture kinetic, humid, and process-level constraints relevant to real operation. Here we establish a dynamic evaluation framework that replaces equilibrium-centric metrics with a unified platform integrating high-precision gravimetric measurements, ppm-level CO 2 nondispersion infrared detection, and capacitive humidity sensing, enabling direct quantification of adsorption kinet…

Evidence: 37 • authority: 72

Fusion power is a potential method of electric power generation from heat released by nuclear fusion reactions. In fusion, two light atomic nuclei combine to form a heavier nucleus and release energy. Devices that use this process are known as fusion reactors. Research on fusion reactors began in the 1940s. As of 2025, the National Ignition Facility (NIF) in the United States is the only laboratory to have demonstrated a fusion energy gain factor above one, but efficiencies orders of magnitude higher are required to reach engineering breakeven (a net electricity-producing plant) or economic breakeven (where the net electricity pays for the plant's whole-life cost). Thermonuclear fusion reac…

Evidence: 37 • authority: 80

KINETIC ENERGY GENERATION AND DISSIPATION IN THE LARGE-SCALE ATMOSPHERIC CIRCULATION

Evidence: 37 • authority: 88

Measuring Turbulent Kinetic Energy Dissipation at a Wavy Sea Surface. Abstract Wave breaking is thought to be the dominant mechanism for energy loss by the surface wave field. Breaking results in energetic and highly turbulent velocity fields, concentrated within approximately one wave height of the surface. To make meaningful estimates of wave energy dissipation in the upper ocean, it is then necessary to make accurate measurements of turbulent kinetic energy (TKE) dissipation very near the surface. However, the surface wave field makes measurements of turbulence at the air–sea interface challenging since the energy spectrum contains energy from both waves and turbulence over the same rang…

Evidence: 37 • authority: 88

Atmospheric boundary layer turbulence in the presence of swell: turbulent kinetic energy budget, Monin-Obukhov similarity theory and inertial dissipation method. <p><span>Turbulence over the mobile ocean surface has distinct properties compared to turbulence over land. This raises the issue of whether functions such as the turbulent kinetic energy (TKE) budget and Monin-Obukhov similarity theory (MOST) determined over land are directly applicable to ocean surfaces because of the existence of a wave boundary layer (the lower part of atmospheric boundary layer including effects of surface waves. We used the term &amp;#8220;WBL&amp;#8221; in this article for convenience), where the total stres…

Evidence: 37 • authority: 92

Reaction-induced departures from continuum Navier-Stokes turbulence.. Reactive hydrodynamic turbulence is an inherently multiscale phenomenon, characterized by the separation between energy-containing, viscous, and molecular length and time scales. The separation between the viscous scale (the Kolmogorov scale) and the molecular mean free path ostensibly justifies a macroscopic description of reactive turbulence via the Navier-Stokes (NS) equations. However, here we use molecular-level simulations to demonstrate that exothermic bimolecular reactions can cause the NS description of turbulence to break down in the near-continuum regime. Sufficiently energetic heat-releasing reactive collision…

Evidence: 37 • authority: 72

Solid is a state of matter in which atoms are closely packed and are difficult to move past each other. Solids resist compression, expansion, or external forces that would alter its shape, with the degree of resistance being dependent upon the specific material under consideration. Solids also always possess the least kinetic energy per atom/molecule relative to other phases or, equivalently stated, solids are formed when matter in a fluid phase (liquid or gas) is cooled below a certain temperature. This temperature is called the melting point of the substance and is an intrinsic property; i.e. independent of how much of the matter there is. The vast majority of substances, when in the soli…