Temperature distribution in a gas conductor heated by direct current

1969 ◽  
Vol 16 (1) ◽  
pp. 27-30
Author(s):  
D. F. Bozhko ◽  
�. I. Molodykh ◽  
A. V. Pustogarov
Keyword(s):  
Temperature Distribution ◽  
Direct Current

scholarly journals Electric Field and Temperature Simulations of High-Voltage Direct Current Cables Considering the Soil Environment

Energies ◽  
2021 ◽  
Vol 14 (16) ◽  
pp. 4910
Author(s):  
Christoph Jörgens ◽  
Markus Clemens
Keyword(s):  
Temperature Distribution ◽  
Electric Field ◽  
High Voltage ◽  
Direct Current ◽  
Insulation Material ◽  
Soil Environment ◽  
High Voltage Direct Current ◽  
Weakly Coupled ◽  
Surrounding Soil ◽  
Symmetric Temperature

For long distance electric power transport, high-voltage direct current (HVDC) cable systems are a commonly used solution. Space charges accumulate in the HVDC cable insulations due to the applied voltage and the nonlinear electric conductivity of the insulation material. The resulting electric field depends on the material parameters of the surrounding soil environment that may differ locally and have an influence on the temperature distribution in the cable and the environment. To use the radial symmetry of the cable geometry, typical electric field simulations neglect the influence of the surrounding soil, due to different dimensions of the cable and the environment and the resulting high computational effort. Here, the environment and its effect on the resulting electric field is considered and the assumption of a possible radial symmetric temperature within the insulation is analyzed. To reduce the computation time, weakly coupled simulations are performed to compute the temperature and the electric field inside the cable insulation, neglecting insulation losses. The results of a weakly coupled simulation are compared against those of a full transient simulation, considering the insulation losses for two common cable insulations with different maximum operation temperatures. Due to the buried depth of HV cables, an approximately radial symmetric temperature distribution within the insulation is obtained for a single cable and cable pairs when, considering a metallic sheath. Furthermore, the simulations show a temperature increase of the earth–air interface above the buried cable that needs to be considered when computing the cable conductor temperature, using the IEC standards.

Characteristics of an underwater direct current discharge in bubbles and the temperature distribution in the bubbles

2012 ◽  
Vol 19 (2) ◽  
pp. 023501 ◽  
Author(s):  
Ranhua Xiong ◽  
Anton Yu. Nikiforov ◽  
Patrick Vanraes ◽  
Christophe Leys
Keyword(s):  
Temperature Distribution ◽  
Direct Current ◽  
Current Discharge ◽  
Direct Current Discharge

Inter-Method Reliability of Pulse Volume Related Measures Derived Using Finger-Photoplethysmography

2018 ◽  
Vol 32 (4) ◽  
pp. 182-190 ◽  
Author(s):  
Kenta Matsumura ◽  
Koichi Shimizu ◽  
Peter Rolfe ◽  
Masanori Kakimoto ◽  
Takehiro Yamakoshi
Keyword(s):  
Light Intensity ◽  
Adverse Effects ◽  
Light Source ◽  
Direct Current ◽  
Resting State ◽  
Current Component ◽  
Psychophysiological Measures ◽  
Pulse Volume ◽  
Optical Paths ◽  
Sensor Positions

Abstract. Pulse volume (PV) and its related measures, such as modified normalized pulse volume (mNPV), direct-current component (DC), and pulse rate (PR), derived from the finger-photoplethysmogram (FPPG), are useful psychophysiological measures. Although considerable uncertainties exist in finger-photoplethysmography, little is known about the extent of the adverse effects on the measures. In this study, we therefore examined the inter-method reliability of each index across sensor positions and light intensities, which are major disturbance factors of FPPG. From the tips of the index fingers of 12 participants in a resting state, three simultaneous FPPGs having overlapping optical paths were recorded, with their light intensity being changed in three steps. The analysis revealed that the minimum values of three coefficients of Cronbach’s α for ln PV, ln mNPV, ln DC, and PR across positions were .948, .850, .922, and 1.000, respectively, and that those across intensities were .774, .985, .485, and .998, respectively. These findings suggest that ln mNPV and PR can be used for psychophysiological studies irrespective of minor differences in sensor attachment positions and light source intensity, whereas and ln DC can also be used for such studies but under the condition of light intensity being fixed.

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