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The purpose of this paper is to test and analyze the friction torque of double-row angular contact ball bearings under vacuum or ordinary pressure environment, horizontal or upright installation mode, and different rotational speeds, and to provide theoretical bases for the development of aerospace equipment.

The experiments were carried out to investigate the effects of vacuum or ordinary pressure environment, horizontal or upright installation mode and different rotational speeds on bearing friction torque. To explore the relationship between working conditions and bearing friction torque, firstly, based on the generation source of friction torque, the test principle was determined, a test system was developed and the reliability of data was verified. Secondly, the friction torque of bearing was tested, and the values under various working conditions were obtained. Finally, this paper compared and discussed the test results.

The test results show that the friction torque value of vacuum environment horizontal installation condition is the largest at different rotational speeds, and the rotational speed has the most significant influence on the friction torque.

The friction torque test system of double-row angular contact ball bearing under vacuum environment was designed and built. The influence rules of vacuum or ordinary pressure environment, horizontal or upright installation mode and different rotational speeds on bearing friction torque were obtained.

The peer review history for this article is available at: http://dx.doi.org/10.1108/ILT-08-2023-0259

This paper aims to derive a reduced-order model for the heat transfer across the interface between a millimetric thermocapillary liquid bridge from silicone oil and the surrounding ambient gas.

Numerical solutions for the two-fluid model are computed covering a wide parametric space, making a total of 2,800 numerical flow simulations. Based on the computed data, a reduced single-fluid model for the liquid phase is devised, in which the heat transfer between the liquid and the gas is modeled by Newton’s heat transfer law, albeit with a space-dependent Biot function Bi(z), instead of a constant Biot number Bi.

An explicit robust fit of Bi(z) is obtained covering the whole range of parameters considered. The single-fluid model together with the Biot function derived yields very accurate results at much lesser computational cost than the corresponding two-phase fully-coupled simulation required for the two-fluid model.

Using this novel Biot function approach instead of a constant Biot number, the critical Reynolds number can be predicted much more accurately within single-phase linear stability solvers.

The Biot function for thermocapillary liquid bridges is derived from the full multiphase problem by a robust multi-stage fit procedure. The derived Biot function reproduces very well the theoretical boundary layer scalings.

COVID-19 pandemic has overturned the work and family life challenging the world in unpredictable ways that were previously unimaginable. With universities shutting down and emergence of online classes, this phenomenon is prevalent among academicians as well. With this background, the current study aims to investigate the direct relationships between workplace isolation (WPI) during COVID-19 and work–family conflict (WFC) with psychological stress (PS) mediating and organizational identification (OI) moderating the relationship between the two.

The authors employed time lagged survey and collected data at three different time intervals (T1, T2, T3) from 203 academicians working across various universities and colleges in India. The data were analyzed quantitatively using SPSS PROCESS Macro and AMOS.

The results indicated that WPI during COVID-19 has a significant positive relationship with PS and WFC . It was also found that PS partially mediated the relationship between WPI during COVID-19 and WFC. Further, OI emerged as a potential moderator.

Based on the current empirical studies, it remains unclear if WPI during COVID-19 is associated with WFC. Therefore, drawing upon stress–strain–outcome (SSO) model and the conservation of resource theory, this study makes a significant contribution to the existing body of literature by exploring the unexplored associations. To the best of the authors’ knowledge, such an association has not received much scholarly attention before.