Application of 3D MHD equilibrium calculation to RMP experiments in the J-TEXT tokamak

Arsenic emission from coal combustion power plants has attracted increasing attention due to its high toxicity. In this study, it was found that there was a close relationship between the ash fusion temperature (AFT) and arsenic distribution based on the thermodynamic equilibrium calculation. In addition to the AFT, coal characteristics and combustion temperature also considerably affected the distribution and morphology of arsenic during coal combustion. Thus, an arsenic volatilization model based on the AFT, coal type, and combustion temperature during coal combustion was developed. To test the accuracy of the model, blending coal combustion experiments were carried out. The experimental results and published data proved that the developed arsenic volatilization model can accurately predict arsenic emission during co-combustion, and the errors of the predicted value for bituminous and lignite were 2.3–9.8%, with the exception of JingLong (JL) coal when combusted at 1500 °C.

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Hamiltonian Approach to Magnetic Fields with Toroidal Surfaces

Zeitschrift für Naturforschung A ◽

10.1515/zna-1985-1001 ◽

1985 ◽

Vol 40 (10) ◽

pp. 959-967

Author(s):

A. Salat

Keyword(s):

Magnetic Field ◽

Hamiltonian System ◽

Magnetic Fields ◽

Constant Pressure ◽

Time Dependent ◽

Hamiltonian Approach ◽

One Dimensional ◽

Mhd Equilibrium ◽

Magnetic Surfaces ◽

Rotational Transform

The equivalence of magnetic field line equations to a one-dimensional time-dependent Hamiltonian system is used to construct magnetic fields with arbitrary toroidal magnetic surfaces I = const. For this purpose Hamiltonians H which together with their invariants satisfy periodicity constraints have to be known. The choice of H fixes the rotational transform η(I). Arbitrary axisymmetric fields, and nonaxisymmetric fields with constant η(I) are considered in detail.Configurations with coinciding magnetic and current density surfaces are obtained. The approach used is not well suited, however, to satisfying the additional MHD equilibrium condition of constant pressure on magnetic surfaces.

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Plasma response measurements of external magnetic perturbations using electron cyclotron emission and comparisons to 3D ideal MHD equilibrium

Plasma Physics and Controlled Fusion ◽

10.1088/0741-3335/58/11/114004 ◽

2016 ◽

Vol 58 (11) ◽

pp. 114004 ◽

Cited By ~ 33

Author(s):

M Willensdorfer ◽

S S Denk ◽

E Strumberger ◽

W Suttrop ◽

B Vanovac ◽

...

Keyword(s):

Electron Cyclotron ◽

Electron Cyclotron Emission ◽

Mhd Equilibrium ◽

Ideal Mhd ◽

Plasma Response ◽

Magnetic Perturbations ◽

Cyclotron Emission

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Assessment of Hydration Degree of Cement in the Fly Ash-Cement Pastes Based on the Calcium Hydroxide Content

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.875-877.177 ◽

2014 ◽

Vol 875-877 ◽

pp. 177-182 ◽

Cited By ~ 2

Author(s):

Xiang Li ◽

Hua Quan Yang ◽

Ming Xia Li

Keyword(s):

Fly Ash ◽

Calcium Hydroxide ◽

Cement Hydration ◽

Ash Content ◽

Content Increase ◽

Hydration Degree ◽

Equilibrium Calculation ◽

Cement Pastes ◽

Cement Ratio ◽

Water Cement Ratio

The hydration degree of fly ash and the calcium hydroxide (CH) content were measured. Combined with the equilibrium calculation of cement hydration, a new method for assessment of the hydration degree of cement in the fly ash-cement (FC) pastes based on the CH content was developed. The results reveal that as the fly ash content increase, the hydration degree of fly ash and the CH content decrease gradually; at the same time, the hydration degree of cement increase. The hydration degree of cement in the FC pastes containing a high content of fly ash (more than 35%) at 360 days is as high as 80%, even some of which hydrates nearly completely. The effect of water-cement ratio to the hydration degree of cement in the FC pastes is far less distinct than that of the content of fly ash.

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