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To guide the stable radius clearance choice of water-lubricated bearings for single screw compressors, this paper aims to analyze the effects of turbulence and cavitation on bearing performance under two conditions of specified external load and radius clearance.

A modified Reynolds equation considering turbulence and cavitation is adopted, based on the Jakobsson–Floberg–Olsson boundary condition, Ng–Pan model and turbulent factors. The equation is solved using the finite difference method and successive over-relaxation method to investigate the bearing performance.

The turbulent effect can increase the hydrodynamic pressure and cavitation. In addition, the turbulent effect can lead to an increase in the equilibrium radius clearance. The turbulent region exhibits a higher load capacity and cavitation rate. However, the increased cavitation negatively impacts the frictional coefficient and end flow rate. The impact of turbulence increases as the radius clearance decreases. As the rotating speed increases, the turbulence effect has a greater impact on the bearing characteristics.

The research can provide theoretical support for the design of water-lubricated journal bearings used in high-speed water-lubricated single screw compressors.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-01-2024-0029/

I aimed to develop a conceptual model of power dynamics focused on an anticipated power consequences in business relationships in a context of high environmental turbulence. I also intended to discuss the theoretical significance of my findings and indicate future research directions.

Conceptual article indicating future research directions.

The proposal of the conceptual model of power dynamics focusing on anticipated power consequences in business relationships.

The limitations of the presented model stem from the critique of the holistic view. My contribution lies in advancing our understanding of power dynamics in business relationships amid significant environmental change. I elucidate how transformative practices relate to power outcomes and value creation in these relationships.

The model highlights the importance of a mindful approach to managing business relationships in a turbulent environment. It emphasizes considering expected power outcomes from activities and their impact on creating value in these relationships.

The proposed concept resonates with systems theory, which emphasizes how different levels of business relationships are interconnected. It enables the analysis of power dynamics at the individual level, such as employees, consumers and local communities. These groups often include the most vulnerable individuals impacted by relational business structures.

The focus on anticipated power consequences of transformative practices triggered by high environmental turbulences, while considering the impact of power distribution of relationship actors on the sharing of benefits and costs.

Water jet propulsion is widely used in various military and civilian fields due to its advantages of simple structure and high propulsion efficiency. The process of mooring involves utilizing specially designed equipment to secure a ship at a designated berth. During the process of water jet propulsion, the single propeller operates within a complex and turbulent three-dimensional flow. Hence, studying the coupling between the water jet propeller and the hull is critical to comprehending the characteristics of the device and the distribution of the flow field in detail.

Firstly, we conducted computational fluid dynamics (CFD)-based self-propulsion calculations to evaluate the interaction between the hull and the propeller. We subsequently analyzed the propeller's performance and the forces acting on the hull to understand how the presence or absence of the hull influenced the water jet propeller. Finally, we performed calculations and analysis of the cavitation characteristics of the coupling between the hull and the water jet propeller, considering different rotational speeds and water depths at the bottom of the pool.

The study demonstrated that the presence of the hull boundary layer under the hull-propeller coupling condition led to reduced uniformity of propeller inlet flow and lower efficiency of the propulsion pump. However, it also increased the bias toward low-flow conditions. Additionally, increasing the impeller speed led to a gradual increase in the cavitation volume within the water jet propeller, resulting in a gradual decrease in the propeller's performance.

This research provides the technical support required for effective design and operation of water jet propulsion systems. This paper involves studying and analyzing the performance and flow field of the coupling between the hull and propeller under mooring conditions with a specified hull model.

This study aims to investigate the rarefaction effects on flow and thermal performances of an equivalent sand-grain roughness model for aerodynamic thrust bearing.

In this study, a model of gas lubrication thrust bearing was established by modifying the wall roughness and considering rarefaction effect. The flow and lubrication characteristics of gas film were discussed based on the equivalent sand roughness model and rarefaction effect.

The boundary slip and the surface roughness effect lead to a decrease in gas film pressure and temperature, with a maximum decrease of 39.2% and 8.4%, respectively. The vortex effect present in the gas film is closely linked to the gas film’s pressure. Slip flow decreases the vortex effect, and an increase in roughness results in the development of slip flow. The increase of roughness leads to a decrease for the static and thermal characteristics.

This work uses the rarefaction effect and the equivalent sand roughness model to investigate the lubrication characteristics of gas thrust bearing. The results help to guide the selection of the surface roughness of rotor and bearing, so as to fully control the rarefaction effect and make use of it.

This paper aims to study the influence of cylindrical texture parameters on the lubrication performance of static and dynamic pressure thrust bearings (hereinafter referred to as thrust bearings) and to optimize their lubrication performance using multiobjective optimization.

The influence of texture parameters on the lubrication performance of thrust bearings was studied based on the modified Reynolds equation. The objective functions are predicted through the BP neural network, and the texture parameters were optimized using the improved multiobjective ant lion algorithm (MOALA).

Compared with smooth surface, the introduction of texture can improve the lubrication properties. Under the optimization of the improved algorithm, when the texture diameter, depth, spacing and number are approximately 0.2 mm, 0.5 mm, 5 mm and 34, respectively, the loading capacity is increased by around 27.7% and the temperature is reduced by around 1.55°C.

This paper studies the effect of texture parameters on the lubrication properties of thrust bearings based on the modified Reynolds equation and performs multiobjective optimization through an improved MOALA.

This study aims to investigate the noise-inducing characteristics during the start-up process of a mixed-flow pump and the impact of different start-up schemes on pump noise.

This study conducted numerical simulations on the mixed-flow pump under different start-up schemes and investigated the flow characteristics and noise distribution under these schemes.

The results reveal that the dipole noise is mainly caused by pressure fluctuations, while the quadrupole noise is mainly generated by the generation, development and breakdown of vortices. Additionally, the noise evolution characteristics during the start-up process of the mixed-flow pump can be divided into the initial stage, stable growth stage, impulse stage and stable operation stage.

The findings of this study can provide a theoretical basis for the selection of start-up schemes for mixed-flow pumps, reducing flow noise and improving the operational stability of mixed-flow pumps.

In this study, the authors propose a novel digital twinning approach specifically designed for controlling transient thermal systems. The purpose of this study is to harness the combined power of deep learning (DL) and physics-based methods (PBM) to create an active virtual replica of the physical system.

To achieve this goal, we introduce a deep neural network (DNN) as the digital twin and a Finite Element (FE) model as the physical system. This integrated approach is used to address the challenges of controlling an unsteady heat transfer problem with an integrated feedback loop.

The results of our study demonstrate the effectiveness of the proposed digital twinning approach in regulating the maximum temperature within the system under varying and unsteady heat flux conditions. The DNN, trained on stationary data, plays a crucial role in determining the heat transfer coefficients necessary to maintain temperatures below a defined threshold value, such as the material’s melting point. The system is successfully controlled in 1D, 2D and 3D case studies. However, careful evaluations should be conducted if such a training approach, based on steady-state data, is applied to completely different transient heat transfer problems.

The present work represents one of the first examples of a comprehensive digital twinning approach to transient thermal systems, driven by data. One of the noteworthy features of this approach is its robustness. Adopting a training based on dimensionless data, the approach can seamlessly accommodate changes in thermal capacity and thermal conductivity without the need for retraining.

While previous research has demonstrated the positive effects of digital business strategies on operational efficiency, financial performance and value creation, little is known about how such strategies influence innovation performance. To address the gap, this paper aims to investigate the impact of a firm’s digital business strategy on its innovation performance.

Drawing on the dynamic capability view, this study examines the mechanism through which a digital business strategy affects innovation performance. Data were collected from 215 firms in China and analyzed using multiple regression and structural equation modeling.

The empirical analysis reveals that a firm’s digital business strategy has positive impacts on both product and process innovation performance. These impacts are partially mediated by knowledge-based dynamic capability. Additionally, a firm’s digital business strategy interacts positively with its entrepreneurial orientation in facilitating knowledge-based dynamic capability. Moreover, market turbulence enhances the strength of this interaction effect. Therefore, entrepreneurial-oriented firms operating in turbulent markets can benefit more from digital business strategies to enhance their knowledge-based dynamic capabilities and consequently improve their innovation performance.

This study contributes to the understanding of how a firm’s digital business strategy interacts with entrepreneurial orientation in turbulent markets to shape knowledge-based dynamic capability, which in turn enhances the firm’s innovation performance.

Drawing upon the resource-based view this study aims to examine the connections between formal and informal business relationships and resource-bridging and adaptive capabilities within the context of foreign subsidiaries of multinational enterprises (MNEs) operating in Thailand. Based on prior literature emphasizing business network ties as sources of competitive advantage in emerging markets, this study extends the discourse by investigating the moderating effects of technological turbulence, power distance and assertiveness.

This study uses a quantitative research approach, using data obtained from a self-administered survey conducted among 168 foreign subsidiaries spanning diverse industries in Thailand. The data were analyzed by using multiple-group structural equation modeling to test the hypothesized relationships.

Cultivating different types of business ties enables foreign subsidiaries to improve different types of capabilities. While interpersonal relationships (i.e. informal businessties) enable them to develop their abilities to combine various resources (i.e. resource-bridging capability), rigid contractual-based relationships (i.e. formal businessties) help them to be more adaptive (i.e. adaptive capability). These relationships are also contingent upon the levels of technological turbulence, host-country power distance and host-country assertiveness.

This research builds upon prior research on network ties and capability building by delineating the specific nature of capabilities. Contradicting to the previous findings, demonstrating a negative relationship between formal business ties and capabilities, this study found that each type of business tie enables foreign subsidiaries to enhance different types of capabilities under different circumstances. Moreover, this study adopts a lens of host-country national culture rather than home-country culture in investigating the moderating effects of power distance and assertiveness.

This study aims to examine the role of performance management systems (PMSs) in enabling logic blending to manage institutional complexity and tensions arising from coexisting institutional logics.

This research uses a case study of an Australian non-government organisation (NGO) operating in an institutional field dominated by the state government, in which policy reform jolted the balance between institutional logics. Data was collected through semi-structured interviews, archival documents and observations.

We find the policy reform required the NGO to transform from a wholly care focus to accommodate a more balanced approach with a focus on care coupled with efficiency, outcome delivery and performance measurement. The NGO responded by revising its purpose, strategy and operational model and by seeking to address the imperatives of two dominant and often competing care and managerial logics. We find this was achieved through logic blending, in which PMSs played a pivotal role, with the formalisation and collaboration processes mobilising different elements of PMSs, mobilising some elements differently or not mobilising some elements at all.

This study highlights the central role of PMSs in managing tensions between and the complexity arising from coexisting institutional logics through logic blending, a form of enduring compromise. This study extends the accounting logics and performance management literature by developing the understanding of what constitutes logic blending and how it is distinct from other forms of compromise.