空间科学学报

1986 Vol. 6, No. 1

Previous Issue | Next Issue

Select articles

Display Method:

Cover

Reexamination of the Viscous Effect in the Solar Wind

Zhao Xue-pu, T. E. Holzer

1986, 6(1): 1-8. doi: 10.11728/cjss1986.01.001

Abstract(1715) PDF 521KB(988)

Abstract:
The Helios observations of the plasma and magnetic field in the high-speed solar wind streams between 1 AU and 0.3 AU are used to examine the radial distribution of the various forces exerted on the streams. It is shown that the classical expression of the viscosity derived in the condition of collision-dominated plasma is not suitable to be used to describe the viscous effect in the high speed wind streams, and the viscous force appears to exist in order to balance the inertial force of the fluid element with the resulting force, which approximates to the solar gravity in value between 0.3 AU and 1 AU. The radial dependence of the real viscous force in the streams is deduced in the present work and the corresponding viscosity is derived by assuming the trend of the real viscosity approaching to the classical viscosity as the helicentric distance decreasing. It is found that the ratio of the real viscosity to the classical one at 1 AU would be equal to or greater than one tenth.

The Dawn-dusk Asymmetry of the Dayside Convection Reversal Location on High Geomagnetic Disturbed Days (Combination of Stare, Triad and AE-C)

Zi Min-yun, E. Nielsen, W. B. Hanson, T. A. Potemra

1986, 6(1): 9-18. doi: 10.11728/cjss1986.01.009

Abstract(1838) PDF 731KB(972)

Abstract:
A combination of convection velocity data from the STARE radar and Atmosphere Explorer C and Field-aligned current data from TRIAD are examined tinder high geomagnetic activity conditions. It is found that the dawnside convection reversal and the boundary of the two field-aligned currents are located at lower invariant latitudes than are the duskside ones. The asymmetry at ionospheric altitudes demonstrates that some kinds of asymmetry in transfer processes of mass, momentum and energy of solar wind particles are also developed in dayside magnetosphere under high magnetic activity condition. It is suggested that this asymmetry derives from the "Garden Hose" angle of the interplanetary magnetic field. It seems that the dawn-dusk asymmetry of the shock structures in Earth's bow shock is related to the phenomena discussed here. Other possibilities are also discussed.

Filamentation Instability of Whistler Wave in the Magnetosphere

Wang Yuan-dian

1986, 6(1): 19-23. doi: 10.11728/cjss1986.01.019

Abstract(1612) PDF 369KB(981)

Abstract:
The filainentation instability of whistler waves in the magnetosphere is analyzed in this paper, and the growth nate is calculated. For propagation path L = 4 and electric field of the wave 1 mV/m, the maximum growth rate is about 0.13/1000 km, the corresponding perpendicular wave length is about 400 km (near the equator region). It is also pointed out that the filaxnentation instability discussed here may offer a nonlinear mechanism for the multi-path propagation of whistlers.

Numerical Examination of Akasofu's Energy Coupling Function

Xu Wen-yao, Shi En-qi

1986, 6(1): 24-32. doi: 10.11728/cjss1986.01.024

Abstract(1846) PDF 611KB(756)

Abstract:
Based on the general formula of the energy transfer rate from the solar wind into the magnetosphere, the coupling mechanism of MHD flow is examined by using solar wind data for a period, of 34 days. It is shown that MHD flow mechanism is valid when B_z<0 (or IMF is southward). In this case the energy transfer rate can be expressed by P =CBT^2/3V^5/3n^1/3sin⁴((3/2). This is dfferent from Akasofu's coupling function, but in good agreement with Murayama & Hakamada, Svalgaard, Murayama, and Holzer & Slavin. The factors influencing the calculations of coupling function are also discussed.

Self-excitation Effect of Scattering of Electromagnetic Radiation in a Strong Magnetic Field

Liu Zu-wei

1986, 6(1): 33-42. doi: 10.11728/cjss1986.01.033

Abstract(1727) PDF 604KB(969)

Abstract:
In light of the solution of electron motion equation in a magnetic field, the electron scattering in response to the incident electromagnetic wave of frequency wi includes the part whose frequency is the same as the cyclotron one besides that of frequency wi. This effect can be called the self-excitation and, except the highfrequency limit, has a considerable influence upon the cross section. In this paper, the modified cross sections of classical non-relativistic electron in the case of both a single electron and cold plasma are. given. The spectrum distribution of electron scattering is discussed, and the Thomson absorption coefficients of magnetized thermal equilibrium plasma are obtained for some typical cases. It is also pointed out that the result here can be applied for many astrophysical aspects such as the spectrum formation of X-ray pulsars.

Ray Direction in a Warm Electron Magnetized Plasma

Wang Zhen-song

1986, 6(1): 43-51. doi: 10.11728/cjss1986.01.043

Abstract(1762) PDF 522KB(1279)

Abstract:
The directions of the group-velocity vectors of waves of various frequencies in a warm-electrons only plasma are given. Some important properties of the direction of group-velocity vectors are revealed. It is shown in particular that there is a plasma wave propagating near the resonant region of the wave in the corresponding cold plasma. The electron plasma wave can link with the ordinary wave or the extraordinary waves. This makes waves capable of propagating in a broader range of angles than in a corresponding cold plasma.

Relationship Between Solar Activities and Thunderstorm Activities in Beijing Area and Northeast Region

Zhuang Hong-chun, Lu Xi-cong

1986, 6(1): 52-59. doi: 10.11728/cjss1986.01.052

Abstract(1828) PDF 579KB(981)

Abstract:
Solar activities may influence atmospheric electric properties, Atmospheric electric properties may play a critical role in the formation of thunderstorm. The effects of solar activities on atmospheric electricity may at last .influence the formation of 'thunderstorm. The analysis of the relationship between IMF section boundary crossing, solar flare, sun spot eleven year cycle variation and thunderstorm index is given using superposition epoch merthod for more than 13000 thunderstorm data from 10 metero-logy stations in Beijing area and Northeast region during 1957 to 1978. The results show that for some year's there exists correlationship between thunderstorm index and positive IMF sectiofn boundary crossing. The thunderstom index increases obviously within three days near crossing and on the seventh day after the crossing. The influence of the crossing on thunderstorm is stronger in the former half year than the latter half year. For different classes of solar flares, the influenced are not equally obvious The solar flares appeared on the weat side, especially in westen region, one (from0° to 30°) have most obvious influence. There is no discernible correlationship between thunderstorm index and sun spot eleven year cycle.

Types and Characteristics of the Extraterrestrial Magnetic Spheres in the Ocean Bottom

Wang Xian-lan, Liang Jing-zhou

1986, 6(1): 60-66. doi: 10.11728/cjss1986.01.060

Abstract(1811) PDF 2113KB(1061)

Abstract:
In this paper, over one hundred and forty magnetic spheres samples obtained in different ways were tested and studied systematically, and one hundred and twelve spheres were divided into three types of origin (cosmic, terrestrial, and of industrial pollution), four, types of genesis (melt, nonmelt, volcanic explosion, and metalspark), and fourteen groups of shape-structure type. Our discussion will centre on the characteristics and signifieance of the magnetic spheres from the universe.

Dynamical Theory of Multi-function Dry-tuned Accelerometer/gyro

Wang Hui-nan

1986, 6(1): 67-75. doi: 10.11728/cjss1986.01.067

Abstract(1757) PDF 584KB(671)

Abstract:
In constrast to symmetric rotor of Dry-tuned GYRO (DTG), the rotor of Dry-tuned accelerometer/GYRO (D'TAG) has different transverse moments of inertia and a proper rotor pendulosity. DTG can be improved to DATG. This instrument provides measurements of angular rate about two axes and linear accelerations along two axes. The study of DTAG is a significant effect on the development of Inertia Navegation System.This paper presents the dynamical equations of DTAG. Under the condition of multi-frequency vibration, the stationary solution is computed according to the analyses of the dynamics. The feasibility of dry-tuned sensor technology for mechanizing an inertia grade four-axes multi-function senson is demonstrated.This paper also presents the condition of eliminating error torques resulting from angular vibration inputs of double spin frequency of the driving shaft. This condition is obtained by way of simple construction of single gimbal GYRO.

Three Dimensional Propagation Characteristics of the Flare-Associated Interplanetary Shock Wave During 1978-1981

Wei Feng-si

1986, 6(1): 76-81. doi: 10.11728/cjss1986.01.076

Abstract(1769) PDF 425KB(942)

Abstract:
The three-dimensional propagation characteristics of the iflare-associated shock wave are studied from Japanese IPS data of 85 flares (importance > 2) events during the period of high-solar activity years of 1978-1981. In this paper, the influnences of the dynamical effects of shock wave propagation on. the IPS data are considered. The results show that: (1) the propagation of the shock wave is asymmetrical relative to the normal direction of the flare. With regard to longitude, -the fastest direction tends to that of the interplanetary magnetic field, and with regard to latitude it tends to that of the average position of the heliospherical current sheet during the period of 85 flare events; (2) propagating range of the latitudes ( - 60°-+40°) is less than that of the longitudes(>±90); (3) there are more marked east-west and south-north asymmetries in the distribution of the shock wave energy, which determine the aniso-tropies of the shock wave propagation. The average energy is about 2.7×10³¹ ergs/ster for the studied 85 flare-IPS shock wave events.These results are Wassieally consistent with that obtained by analysing American IBS data^[3], and also coincident with that of the spacecraft observations tod the indirect results of inverstigations 7-8. So it is reasonable to think that the magnetic structures near the sun and the interplanetary large-scale solar wind structures would exert significant modulating effects on the three-dimensional propagation of the shock wave.

Qn the Stress Analysis and the Shape Design of the Scientific Balloon at High Altitude

Huang Wu-liang, Xu Chun-xian, Wu Mei, Gu Yi-dong, Xu Zong-xing

1986, 6(1): 82-88. doi: 10.11728/cjss1986.01.082

Abstract(2105) PDF 405KB(1018)

Abstract:
An analysis of the stress of the zero pressure balloon membrance with rotational symmetry is presented, and the reasonable shapes can be designed by choosing rational restrain conditions of the latitude stress t. We propose the following three principles for σ_t: (1) in the lower hemilballoon,σ_t≈0;(2) then, σ_t gradually increases from the middle to the top of the balloon; (3) near the top, the longitude stress σ_t≈0.According to these principles, one can design balloons with or without reinforce tapes, both have the maximum stress and the total stress energy much less than that in ordinary designs with σ_t=0. So., such types wiljl be adopted in the design of giant ballootn.