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In the magnetorheological fluid (MRF) sealing, a large amount of friction heat is generated in the fluid film with micron thickness due to the viscosity dissipation, which leads to seal failure and MRF deterioration. The purpose of this study is to investigate the mechanism of temperature rise of MRF film under the action of the three-field coupling of the flow field, temperature field and magnetic field.

The fluid film was simplified as a Couette flow in this work to simulate the temperature change in the sealing fluid film under different working conditions. The corresponding experiment for test the temperature rise was also carried out, and the temperature of the characteristic point of the stationary ring was measured to validate the model.

The results show that the temperature rise is mainly affected by the rotational speed, magnetic field strength and fluid film thickness. The magnetic field enhances the convective heat transfer in the MRF film. The thinner the fluid film, the more frictional heat generated. The MRF film reaches its maximum temperature at the contact with the end face of rotating ring due to frictional heat.

A method for temperature rise analysis of MRF fluid sealing films based on Couette flow is established. It is helpful for the study of liquid film frictional heat in MRF seals.

The achievement of self-reliance (zi li geng sheng: “regeneration through one's own efforts”) is an important Chinese goal. Mao Zedong's approach to achieving this goal after 1960 was to advocate and practice economic self-sufficiency both within China and nationally. One purpose of this article is to outline and discuss Mao's approach and its consequences. Following China's market reforms commencing in 1978, Mao's economic self-reliance policies were systematically abandoned. The second aim of this article is to consider how China's market reforms and its development have impacted on subnational economic self-reliance within China and to assess the extent to which its open-door policy has reduced its national self-reliance.

Secondary sources and data are used to develop this article.

As a result of its market reform and economic development, all parts of China's economy have become more interdependent and continue to do so. In addition, China has become more dependent for its economic welfare on international trade, but its dependence is much less than that of many other countries, for example, Germany. Nevertheless, the Chinese still endeavour to be masters of their own destiny. From this perspective, Mao's principle of self-reliance has not been abandoned.

Despite its growing economic interdependence, China continues to value its capacity for autonomous goal setting and decision-making. This is illustrated by the strategies it has adopted to address its dependency on oil imports. Nevertheless, China's increased economic interdependence adds to China's challenges and difficulties in controlling its economic affairs.