R.K. Duvedi, Manpreet Singh and V.K. Jadon
The present work aims to predict accurately the bearing design data for non‐recessed hybrid journal bearings, considering the effect of non‐Newtonian behavior of lubricant for…
Abstract
Purpose
The present work aims to predict accurately the bearing design data for non‐recessed hybrid journal bearings, considering the effect of non‐Newtonian behavior of lubricant for different symmetric and non‐symmetric bearing geometric configurations.
Design/methodology/approach
The simultaneous solution of generalized Reynold's equation governing the laminar flow of incompressible lubricant and the equation of flow of lubricant through the capillary restrictor, considering variable viscosity of lubricant following the “Power law”, has been carried out using FEM. For a given set of bearing geometric, operating parameters and for given external vertical load, the values of various performance characteristics have been obtained for a range of values of power law index, after establishing the journal center equilibrium position, the analysis for which has been elaborately explained.
Findings
The results obtained have been presented graphically for various bearing performance characteristics. It has been observed that with decrease in power law index “n”(0<n≤1), the value of h¯min and load carrying capacity decreases, while bearing flow rate increases for all configuration. The load‐carrying capacity of asymmetric configurations is better and stable over entire range of restrictor design parameter. Bearing configuration with land width ratio = 0.25 and aspect ratio = 1.0, having two rows of holes and six holes in each row, will be better suited for high‐load support, as it has maximum value of minimum fluid film thickness, moderate value of bearing flow and value of attitude angle is almost constant.
Originality/value
The performance characteristics of journal bearing have been presented for a wide range of values of power law index and for different values of restrictor design parameter for capillary restrictor, after establishing the journal center equilibrium position. The comparison of the different symmetric and non‐symmetric journal‐bearing configurations to find the best geometric configuration at different operating conditions, considering the effect of non‐Newtonian behavior of lubricant, represents the originality of the work.
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H.C. Garg and Vijay Kumar
This paper aims to investigate the effect of plugging of holes on the static performance characteristics of a constant flow valve compensated hole‐entry hybrid journal bearing…
Abstract
Purpose
This paper aims to investigate the effect of plugging of holes on the static performance characteristics of a constant flow valve compensated hole‐entry hybrid journal bearing system operating with Newtonian and non‐Newtonian lubricants. The analysis considers the generalized Reynolds equation governing the flow of lubricant having variable viscosity in the clearance space and equation of flow of lubricant through constant flow valve restrictor. The non‐Newtonian lubricant is assumed to follow the power law. The performance characteristics are computed for the two values of power law index (n=1.0 and 0.566). The computed results indicate that the blockage of holes during operation will not be the likely causes for the imminent failure of a well‐designed non‐recessed hole‐entry hybrid journal bearing.
Design/methodology/approach
Finite element method has been used to solve generalized Reynolds equation governing the flow of lubricant having variable viscosity in the clearance space and equation of flow of lubricant through constant flow valve restrictor.
Findings
The computed results indicate that the blockage of holes during operation will not be the likely causes for the imminent failure of a well‐designed non‐recessed hole‐entry hybrid journal bearing. The bearing configuration with plugged holes provides sufficient fluid film thickness and low power requirement as less lubricant is required to be pumped in the bearing.
Originality/value
To the best of the author's knowledge, no study which considers the influence of plugging of holes on the static performance characteristics of a constant flow valve compensated hole‐entry hybrid journal bearing system operating with Newtonian and non‐Newtonian lubricant is yet available in the literature.
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H.C. Garg and Vijay Kumar
The changing technological scenario necessitated hybrid journal bearings to operate under severe conditions of heavy load and high speed resulting into temperature rise of the…
Abstract
Purpose
The changing technological scenario necessitated hybrid journal bearings to operate under severe conditions of heavy load and high speed resulting into temperature rise of the lubricant fluid-film and bearing surface. To predict the performance of a bearing realistically, theoretical model must consider the combined influence of the rise of temperature and non-Newtonian behavior of the lubricant. The aim of the present paper is to study the effect of viscosity variation due to temperature rise and non-Newtonian behavior of the lubricant on performance of constant flow valve compensated multiple hole-entry hybrid journal bearings.
Design/methodology/approach
Finite element method has been used to solve Reynolds equation along with restrictor flow equation, 3D energy equation and 3D conduction equation using suitable iterative technique. The non-Newtonian lubricant has been assumed to follow cubic shear stress law.
Findings
The thermohydrostatic rheological performances of symmetric and asymmetric hole-entry hybrid journal bearing configurations are studied. The computed results illustrate that variation of viscosity due to rise in temperature and non-Newtonian behavior of the lubricant affects the performance of hole-entry hybrid journal bearing system quite significantly.
Originality/value
In the present work, the influences of the viscosity variation due to temperature rise and non-Newtonian behavior of the lubricant on the performance characteristics of non-recessed hole-entry hybrid journal bearing with symmetric and asymmetric configurations compensated with constant flow valve restrictors have been investigated for generating the design data to be used by bearing designer. The design data computed in the present thesis are a contribution in field of knowledge of bearing design.
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Rajneesh Kumar and Suresh Verma
In the present scenario of high-speed machines, the use of non-circular hole-entry bearing configuration, i.e. two-lobe, multi-lobe, lemon bore, etc., has becomes unavoidable, as…
Abstract
Purpose
In the present scenario of high-speed machines, the use of non-circular hole-entry bearing configuration, i.e. two-lobe, multi-lobe, lemon bore, etc., has becomes unavoidable, as the journal bearings with non-circular configurations provide better stability at high operating speed and heavy dynamic loading. Further, this research aims to show that the presence of micro particles in the lubricants greatly affects performance of the bearings, as their presence leads to non-Newtonian behaviors of the lubricant. Therefore, to consider the effect of these micro particles, the lubricant is modeled as a micropolar lubricant. The present work analyzes the effect of these micropolar lubricants on the performance of hole-entry circular and non-circular (two-lobe) hybrid journal bearings compensated with constant flow valve restrictor and compares with that of Newtonian lubricants.
Design/methodology/approach
The modified Reynolds equation governing the laminar flow of iso-viscous, incompressible micropolar lubricant in the clearance space of a journal bearing system has been solved using finite element method and appropriate boundary conditions. Further, a comparative analysis between circular and non-circular (two-lobe) hybrid journal bearing compensated with constant flow valve restrictor operating with Newtonian and micropolar lubricant has been presented.
Findings
The numerically simulated results reveal that the non-circular bearing configuration provides better performance vis-à-vis the circular bearing configuration. Further, the increase in the micropolar effect of the lubricant enhances the performance of circular and the non-circular bearing configurations compared with the Newtonian lubricant. Also, in the case of the non-circular bearing configuration with an offset factor (δ = 1.5), the bearing performance improved compared with (δ = 1.25).
Originality/value
Many research studies have been done in the area of non-circular hybrid journal bearing with Newtonian lubricants with different types of restrictors, but the non-circular hole-entry constant flow valve-compensated hybrid journal bearing operating with the micropolar lubricant has not been analyzed. Therefore, in the present work, an effort has been made to fill this research gap.
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Kimberly W. O’Connor and Gordon B. Schmidt
Purpose – This chapter explores the topic of free speech protections and social media use in academia through an examination of the current legal landscape as it applies to…
Abstract
Purpose – This chapter explores the topic of free speech protections and social media use in academia through an examination of the current legal landscape as it applies to various stakeholders on university campuses in the United States. The authors focus this examination primarily on public universities. Methodology/Approach – Legal research methods were utilized, including an analysis of relevant United States federal and state laws, case law, and secondary sources such as law reviews. Non-legal sources, such as academic journals, were also reviewed, with particular emphasis on topics such as university policies, tenure protections, academic freedom, as well as current events. Findings – The law regarding personal social media communications in a university setting is a series of complex and interconnected legal questions. Courts are still flushing out how free speech protections, personal social media use, and other relevant legal protections (e.g., employment law) may interface in a university-related case. Outcomes of cases are highly fact driven, and legal precedent is still being established. Originality/Value – This chapter offers a comprehensive examination of the topic of free speech and social media use in United States academia by (1) examining legal protections as applied to various stakeholders on a college campus and (2) analyzing the current legal landscape of social media cases involving universities.
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Abhijeet Tewary and Vaishali Jadon
This research aims to analyze the literature on Quality 4.0 and pinpoint the essential factors contributing to its success. Additionally, the research aims to develop a framework…
Abstract
Purpose
This research aims to analyze the literature on Quality 4.0 and pinpoint the essential factors contributing to its success. Additionally, the research aims to develop a framework that can be used to create a capable workforce necessary for the successful implementation of Quality 4.0.
Design/methodology/approach
By following a systematic approach, the authors could ensure that their literature review was comprehensive and unbiased. Using a set of pre-determined inclusion and exclusion criteria, the authors screened 90 research articles to obtain the most relevant and reliable information for their study.
Findings
The authors' review identified essential findings, including the evolution of literature in the field of Quality 4.0 and the systematization of previous literature reviews focusing on training and development. The authors also identified several training barriers to implementing Quality 4.0 and proposed a model for building a competent workforce using Kolb's experiential learning model.
Practical implications
The authors' research offers insights into the training barriers that must be considered when building a competent workforce. Using the framework proposed in the authors' research, consultants and managers can better integrate Quality 4.0 into their organizations.
Social implications
The adoption of Quality 4.0 has significant social implications and is essential for advancing sustainability. It can improve efficiency, reduce waste, minimize environmental impacts and better meet the needs and expectations of stakeholders.
Originality/value
The authors' study stands out as one of the earliest reviews of the literature on Quality 4.0 to incorporate the theory-context-method (TCM) framework, allowing to provide unique insights into future research directions that had not been previously explored.
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Biomimicry is an interdisciplinary approach inspired by the living beings in nature while searching for solutions to solve mankind’s problems. This new approach emerging in the…
Abstract
Biomimicry is an interdisciplinary approach inspired by the living beings in nature while searching for solutions to solve mankind’s problems. This new approach emerging in the late 1990s has been quite innovative while dealing with basic problem solving processes in a business environment. Biomimicry is a creative solution for such processes as design, transformation, organization and sustainability in business enterprises. The objective of this work is to offer model samples that build a bridge between the nature and business organizations. The principles in nature offer many strategies for a sustainable business performance and thus help us maintain optimization and effectiveness in business management through cooperation.
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Suresh Verma, Vijay Kumar Jadon and K.D. Gupta
The paper seeks to study, theoretically, the performance characteristics of capillary compensated multi‐recessed hydrostatic journal bearings operating with micropolar lubricant…
Abstract
Purpose
The paper seeks to study, theoretically, the performance characteristics of capillary compensated multi‐recessed hydrostatic journal bearings operating with micropolar lubricant. The finite element method is used to solve the modified Reynolds' equation governing the micropolar lubricant flow in the clearance space of a hydrostatic journal bearing. The performance characteristics of bearing operating with micropolar lubricant are presented and compared with that of Newtonian lubricant, for a wide range of non‐dimensional load, capillary restrictor design parameter and micropolar parameters.
Design/methodology/approach
The modified Reynolds' equation governing the flow of the micropolar lubricant is solved along with restrictor flow equation by finite element method so as to obtain fluid‐film pressures. The iterative procedure is repeated until the converged solution for the fluid‐film pressure field is obtained.
Findings
A study of four‐pocket hydrostatic journal bearing system capillary compensated and operating with micropolar lubricant is presented. The following conclusions are made from the results presented in this study: at a constant load, pocket pressures and minimum film thickness, stiffness coefficients and, the damping coefficients increase with increase in micropolar effect of lubricant as compared to the Newtonian lubricant; the influence of the micropolar parameters of lubricant is more significant upon the minimum fluid‐film thickness at higher values of load and lower values of restrictor design parameter; the non‐dimensional flow decreases with increase in the micropolar effect of the lubricant a given values of restrictor design parameter and load; and the stiffness coefficient in the direction of load is found to be influenced by the micropolar parameters and more significantly at lower values of restrictor design parameter and load.
Originality/value
Studies of capillary compensated multi‐recess hydrostatic journal bearing operating with micropolar fluid/lubricant are not available in the existing literature to the best of authors' knowledge. Although, such bearing has been studied with Newtonian lubricant and available in open literature. Therefore, this paper is an original piece of work in the area of micropolar lubrication and compensated hydrostatic bearings.
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This paper aims to emphasize the need for a strategic approach to employee retention beyond financial benefits. This is directly proportional to employee retention. Bringing out…
Abstract
Purpose
This paper aims to emphasize the need for a strategic approach to employee retention beyond financial benefits. This is directly proportional to employee retention. Bringing out the retention measures preferred by employees, depicting the relationship of demographic profile with employee retention tendency and exploring implications giving importance to beyond paycheque factors are the objectives of the study.
Design/methodology/approach
This study uses applied qualitative approach with a realistic view to collect the details of retention measures and practices from purposively selected 36 health-care experts by the conduct of interview using a one-to-one discussion with written notes. With quantitative approach, opinion survey was administered to receive the perceived opinion of randomly selected 350 health-care employees on paycheque and on beyond paycheque factors boosting their intention to stay. Bhattacharya and Ramachandran’s health-care study framework on retention was applied for the identification of the factors.
Findings
Both paycheque and beyond paycheque benefits are important for retention. Most respondents prefer beyond paycheque factors practiced at sampled hospital. Age, marital status and residence of employees are significantly associated with retention. The strategic initiatives of the sampled hospital to retention concerning motivational needs of employees in the workplace are thank you board, camp head, ad act camp, success corner and so forth.
Research limitations/implications
Addressing health-care work and relationship-related issues in terms of employee retention giving importance to beyond paycheque benefits – remedy for compassion fatigue health-care employees face in routine works, meeting promises made by management regarding paycheque or beyond paycheque benefits, employees participative in decisions in medical, clinical and in functional areas, reducing workload and role stress by the conduct of role analysis.
Originality/value
Many research studies are emphasizing the contribution of financial benefits to employee retention. Only a few studies have been carried out exploring and emphasizing the importance of beyond financial benefits motivating employee retention. This is the study of evidence from a hospital that gives strategic importance to beyond paycheque elements as well as paycheque elements.