Shock-induced energy conversion of entropy in non-ideal fluids

2019 ◽  
Vol 864 ◽  
pp. 807-847 ◽  
Author(s):  
Emile Touber ◽  
Nicolas Alferez
Keyword(s):  
Thermodynamic Properties ◽  
Critical Point ◽  
Inertial Confinement Fusion ◽  
High Speed ◽  
Theoretical Work ◽  
Ideal Gas ◽  
Supersonic Combustion ◽  
Experimental Investigations ◽  
Inertial Confinement ◽  
Sound Waves

From shaping cosmic structures in space to producing intense sounds in aircraft engines, shock waves in fluids ineluctably convert entropy fluctuations into swirling motions and sound waves. Studies of the corresponding conversion from internal energy to kinetic energy have so far been restricted to ideal (or idealised) fluids. Yet, many substances do not obey the ideal-gas law (including those in the above two examples). The present work demonstrates that non-ideal thermodynamic properties provide a remarkable degree of control over the conversion to solenoidal and dilatational kinetic energies. Of particular interest is the ability to suppress much of the emitted acoustic field whilst promoting mixing downstream of the shock. This is made possible by exploiting the convexity (or lack thereof) of the shock adiabats. Whilst illustrated here using dense vapours near the thermodynamic critical point, this ability to design and control specific shock-induced energy transfers extends beyond near-critical-point phenomena; e.g. shocked mixtures (high-speed dusty flows on Mars, nanoparticle formation in supersonic expanders for drug manufacturing), reacting fronts (supersonic combustion, rocket propulsion), ionising shocks (reentry systems, inertial confinement fusion) or fronts in active fluids (bacterial and crowd flows). This theoretical work, which demonstrates the predictive capabilities of linear theory, lays the foundation for future experimental investigations ultimately aimed at delivering novel shock-based flow-control strategies exploiting the thermodynamic properties of the fluid.

scholarly journals A Novel Spectrometer for Measuring Laser-Produced Plasma X-Ray in Inertial Confinement Fusion

2012 ◽  
Vol 2012 ◽  
pp. 1-5
Author(s):  
Zhu Gang ◽  
Xiong Xian-cai ◽  
Zhong Xian-xin ◽  
Yang Yan
Keyword(s):  
Inertial Confinement Fusion ◽  
Bragg Diffraction ◽  
Bragg Angle ◽  
Experimental Investigations ◽  
Inertial Confinement ◽  
Crystal Spectrometer ◽  
Temperature Plasma ◽  
X Ray ◽  
Laser Produced Plasma ◽  
Confinement Fusion

In the experimental investigations of inertial confinement fusion, the laser-produced high-temperature plasma contains very abundant information, such as the electron temperature and density, ionization. In order to diagnose laser-plasma distribution in space and evolution in time, an elliptical curved crystal spectrometer has been developed and applied to diagnose X-ray of laser-produced plasma in 0.2~2.46 nm region. According to the theory of Bragg diffraction, four kinds of crystal including LiF, PET, MiCa, and KAP were chosen as dispersive elements. The distance of crystal lattice varies from 0.4 to 2.6 nm. Bragg angle is in the range of 30°~67.5°, and the spectral detection angle is in 55.4°~134°. The curved crystal spectrometer mainly consists of elliptical curved crystal analyzer, vacuum configuration, aligning device, spectral detectors and three-dimensional microadjustment devices. The spectrographic experiment was carried out on the XG-2 laser facility. Emission spectrum of Al plasmas, Ti plasma, and Au plasmas have been successfully recorded by using X-ray CCD camera. It is demonstrated experimentally that the measured wavelength is accorded with the theoretical value.

scholarly journals Radiation-induced conductivity: High-speed detection of X rays and neutrons

1991 ◽  
Vol 9 (1) ◽  
pp. 91-97 ◽  
Author(s):  
D. R. Kania
Keyword(s):  
Inertial Confinement Fusion ◽  
High Speed ◽  
Carrier Lifetime ◽  
Theoretical Models ◽  
High Energy ◽  
Dead Layer ◽  
Bulk Property ◽  
Inertial Confinement ◽  
X Rays ◽  
Radiation Induced

Radiation-induced conductivity (RIC) is a generalized term for photoconductivity expanded to include nonelectromagnetic radiation. RIC offers several distinct advantages for the detection of high-energy radiation: (i) the speed of response of a detector is determined by a bulk property of the material, the carrier lifetime; (ii) the detector can be directly illuminated by the signal radiation-no dead layer; and (iii) the selection of the detector material and its geometry is very flexible. This paper will discuss the principles of RIC for X rays and neutrons, the fabrication of detectors, and applications. RIC detectors have been fabricated from Si, InP, GaAs, and diamond. Bulk and thin film materials have been used. The carrier lifetime was varied by the introduction of trapping sites in the material. This can be done in the material production process in the case of doping (e.g., Fe in InP) and thin films or produced from radiation damage of a pure crystalline material. Lifetimes as short as a few picoseconds have been observed. A variety of detectors have been tested using pulsed optical, X ray, and neutron sources. Absolute sensitivities and temporal response has been measured and compared to theoretical models of the detector's performance for both X rays and neutrons. Finally, applications of these detectors to inertial confinement fusion measurement will be shown.

scholarly journals Equation of state and optimum compression in inertial fusion energy

2007 ◽  
Vol 25 (4) ◽  
pp. 585-592 ◽  
Author(s):  
S. Eliezer ◽  
M. Murakami ◽  
J.M. Martinez Val
Keyword(s):  
Equation Of State ◽  
Inertial Confinement Fusion ◽  
Nuclear Reactions ◽  
Fusion Energy ◽  
Ideal Gas ◽  
Energy Output ◽  
Inertial Confinement ◽  
Normal Density ◽  
Fuel Mass ◽  
High Compression

AbstractThe inertial confinement fusion (ICF) philosophy is based on high compression. The reasoning is that (a) it is cheaper (energetically) to compress than to heat and (b) nuclear reactions are proportional to density square, therefore the more you compress the better you are in ICF. Of course the only limitations of compression are the hydrodynamic instabilities (like Rayleigh-Taylor, etc). Many of the references in the literature require extremely high compression and in particular the pB11 needs extremely huge compressions. In this paper it is shown that there is an optimum of compression, namely gain G is maximum for a definite compression. The value of this density (for a given fuel mass and particular ICF scheme) depends on the equation of state (EOS). We calculate this value for fast ignition (FI) schemes and compare it with the central spark ignition (CSI) model. The gain calculations are based on the ideal gas for the ions and the Fermi-Dirac EOS for the electrons with an effective alpha, as usually suggested from simulations. The “optimum compression” idea is easily understood from the following argument: From EOS data one needs an infinite energy to compress to an infinite density. Since the energy output is finite it is clear that G is zero for infinite compression. On the other hand for normal density with small fuel mass (~ few mg) the gain is also zero. Therefore a maximum should exist somewhere. For the deuterium-tritium fuel with a mass of few mg one gets an optimum at few hundred g/cc. If you compress more then the gain is going down. So there is a desired maximum compression fixed by EOS. Last but not least, bremsstrahlung losses in degenerate plasma are discussed and the clean fusion (i.e., without neutrons) of proton + B11 → 4α is analyzed.

scholarly journals Equation of state problems in inertial confinement fusion

1985 ◽  
Vol 3 (3) ◽  
pp. 207-236 ◽  
Author(s):  
Shalom Eliezer ◽  
Aaron D. Krumbein ◽  
Henrique Szichman ◽  
Heinrich Hora
Keyword(s):  
Equation Of State ◽  
Inertial Confinement Fusion ◽  
Ideal Gas ◽  
Inertial Confinement ◽  
Self Similarity ◽  
Confinement Fusion ◽  
Linear Force ◽  
Isothermal Diagrams ◽  
Two Temperature ◽  
The Ideal

An analysis is made of the equation of state problems in inertial confinement fusion. After reviewing the need for compression for inertial confinement fusion along the lines of the classical self similarity model which is derived in a modified way with indications of the equation of state, the problems of the central core ignition are examined with respect to the equation of state. A basic difficulty is elaborated in the ‘scape goat diagram’. After describing alternative compression schemes such as non-linear force and cannon ball, the two temperature equation of state is developed with electronic and ionic contributions following the ideal gas, the Debye-Grüneisen equation of state, the solid-gas interpolation and the SESAME tables. A remarkable discrepancy for the isothermal diagrams is shown between the general result and the result based on the earlier McCarthy–Kalitkin scheme.

scholarly journals Cold compression of solid matter by intense heavy-ion-beam-generated pressure waves

2004 ◽  
Vol 22 (1) ◽  
pp. 59-63 ◽  
Author(s):  
C. CONSTANTIN ◽  
E. DEWALD ◽  
C. NIEMANN ◽  
D.H.H HOFFMANN ◽  
S. UDREA ◽  
...  
Keyword(s):  
Shock Waves ◽  
Inertial Confinement Fusion ◽  
Ion Beam ◽  
Heavy Ion ◽  
Spatial Density ◽  
Experimental Investigations ◽  
Inertial Confinement ◽  
Density Profiles ◽  
Confinement Fusion ◽  
Fundamental Research

Experimental investigations of heavy-ion-generated shock waves in solid, multilayered targets were performed by applying a Schlieren and a laser-deflection technique. Shock velocity and the corresponding pressures, temporal and spatial density profiles inside the material compressed by multiple shock waves, and details of the shock dynamics were determined. Important for equation-of-state and phase transition studies, such experiments extend their relevance to inertial confinement fusion and astrophysical fundamental research.

Real gas Brayton cycles for organic working fluids

2001 ◽  
Vol 215 (1) ◽  
pp. 27-38 ◽  
Author(s):  
G Angelino ◽  
C Invernizzi
Keyword(s):  
Thermodynamic Properties ◽  
Critical Point ◽  
Molar Fraction ◽  
Ideal Gas ◽  
Saturation Curve ◽  
Compression Process ◽  
Critical Temperatures ◽  
Working Fluids ◽  
Practical Applications ◽  
Rotating Speed

Organizing a closed Brayton cycle in such a way that the compression process is performed in the vicinity of the critical point where specific volumes are a fraction of those of an ideal gas yields performance indices particularly attractive, mainly at moderate top temperatures. Cycle thermodynamic analysis requires the development of adequate methods for the computation of thermodynamic properties above the vapour saturation curve about the critical point. Working fluids suitable for the proposed cycle can be found in the class of organics, in particular among the newly developed, zero ozone depletion potential, chlorine-free compounds. The numerous technical and environmental requirements which a fluid must meet for practical use combined with the peculiar thermodynamic restraints limit the number of suitable fluids. Mixing two substances of different critical temperatures yields an indefinite number of fluids with tailor-made thermodynamic properties. One such mixture 0.93 HFC23 + 0.07 HFC125 (molar fraction), having tcr = 30°C, at tmax = 400°C, pmax = 150 bar, gives an efficiency above 27 per cent with heat rejection temperatures between 89 and 33°C. With a different mixture composition with a 50°C critical temperature, at the same tmax and pmax, an efficiency of 25.1 per cent is attained in a combined heat and power generation cycle with heat available in the range 53-103°C. An experimental programme to test the thermal stability of organic fluids showed that top temperatures of 380-450°C are achievable with some commercially available fluoro-substituted hydrocarbons. In view of practical applications a conversion unit based on a reciprocating engine could handle without problems the pressures and temperatures involved. The use of turbomachinery would lead to power plant of large capacity for the usual rotor dimensions or to micro-turbines at high rotating speed in the low power range.

scholarly journals Fusion reactions and matter–antimatter annihilation for space propulsion

2006 ◽  
Vol 24 (4) ◽  
pp. 605-616 ◽  
Author(s):  
CLAUDE DEUTSCH ◽  
NAEEM A. TAHIR
Keyword(s):  
Inertial Confinement Fusion ◽  
High Speed ◽  
Power Plants ◽  
Fusion Reaction ◽  
Specific Impulse ◽  
Weight Ratio ◽  
Inertial Confinement ◽  
Fusion Reactions ◽  
Antiproton Annihilation ◽  
Confinement Fusion

Magnetic confinement fusion (MCF) and inertial confinement fusion (ICF) are critically contrasted in the context of far-distant travels throughout solar system. Both are shown to potentially display superior capabilities for vessel maneuvering at high speed, which are unmatched by standard cryogenic propulsion (SCP). Costs constraints seem less demanding than for ground-based power plants. Main issue is the highly problematic takeoff from earth, in view of safety hazards concomitant to radioactive spills in case of emergency. So, it is recommended to assemble the given powered vessel at high earth altitude ∼ 700 km, above upper atmosphere. Fusion propulsion is also compared to fission powered one, which secures a factor of two improvement over SCP. As far a specific impulse (s) is considered, one expects 500–3000 from fission and as much as 104–105 from fusion through deuterium–tritium (D-T). Next, we turn attention to the most performing fusion reaction, i.e., proton–antiproton annihilation with specific impulse ∼ 103–106 and thrust–to–weight ratio ∼ 10−3–1. Production and costs are timely reviewed. The latter could drop by four orders of magnitude, which is possible with successful MCF or ICF. Appropriate vessel designs will be presented for fusion as well as for antimatter propulsion. In particular, ion compressed antimatter nuclear II (ICAN-II) project to Mars in 30 days with fusion catalyzed by 140 ng of antiprotons will be detailed (specific impulse ∼ 13500 s).

Analysis of electroless nickel thin films

1991 ◽  
Vol 49 ◽  
pp. 510-511 ◽  
Author(s):  
C. W. Price ◽  
E. F. Lindsey
Keyword(s):  
Thin Films ◽  
Inertial Confinement Fusion ◽  
Electroless Nickel ◽  
Inertial Confinement ◽  
Plating Bath ◽  
X Ray ◽  
Nickel Thin Films ◽  
Nickel Deposits ◽  
Confinement Fusion ◽  
Thickness Measurements

Thickness measurements of thin films are performed by both energy-dispersive x-ray spectroscopy (EDS) and x-ray fluorescence (XRF). XRF can measure thicker films than EDS, and XRF measurements also have somewhat greater precision than EDS measurements. However, small components with curved or irregular shapes that are used for various applications in the the Inertial Confinement Fusion program at LLNL present geometrical problems that are not conducive to XRF analyses but may have only a minimal effect on EDS analyses. This work describes the development of an EDS technique to measure the thickness of electroless nickel deposits on gold substrates. Although elaborate correction techniques have been developed for thin-film measurements by x-ray analysis, the thickness of electroless nickel films can be dependent on the plating bath used. Therefore, standard calibration curves were established by correlating EDS data with thickness measurements that were obtained by contact profilometry.

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