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Article
Publication date: 7 August 2023

Rui Dan, Yujie Zheng, ZhiQin Liu and Zhen Shi

The inward displacement perpendicular to the body surface produced by compression garment is an important index to evaluate pressure comfort and optimal design of tight clothing…

Abstract

Purpose

The inward displacement perpendicular to the body surface produced by compression garment is an important index to evaluate pressure comfort and optimal design of tight clothing products. The purpose of this study is to explore the pressure distribution state at waist position of elastic legwear and then to solve the common problem of excessive pressure or easy slippage for waist of elastic legwear.

Design/methodology/approach

In this paper, the authors obtained the waist cross-section model of human body using CT scanning and mimics modeling and then simulated the pressure and displacement distribution after wearing sample four elastic legwear using finite element method. The dressing process of elastic legwear was divided into six periods (instantaneous, 1, 2, 4, 8 and 12 h) in this study, and the finite element software ANSYS was used to simulate the displacement and deformation of the waist cross section. The authors finally obtained the functional relationship between pressure/displacement ratio and angle using curve fitting.

Findings

In this paper, the authors obtained the functional relationship between pressure/displacement ratio and angle using curve fitting. Comparison found that the “pressure/displacement–angle” function curve showed an almost consistent trend at any time. That was to say, when the human body was in the state of clothing pressure, the corresponding displacement value of the human body can be calculated by the curve equation under the premise of known pressure value.

Originality/value

This study solves the difficult problem which hard to measure displacement values by conventional methods due to the small deformation of the human body after dressing the compression garment. Conclusions also provide a theoretical reference for evaluating pressure comfort and optimizing clothing structure for the elastic legwear, and this method is also applicable to other types of compression garment.

Details

International Journal of Clothing Science and Technology, vol. 35 no. 5
Type: Research Article
ISSN: 0955-6222

Keywords

Article
Publication date: 1 April 1956

An axial flow turbojet engine in which the mean direction of flow of working fluid past any moving blade is substantially free from radial components comprising a casing; an air…

Abstract

An axial flow turbojet engine in which the mean direction of flow of working fluid past any moving blade is substantially free from radial components comprising a casing; an air intake in said casing; a low‐pressure axial‐flow compressor mounted in said casing, connected directly to said air intake to receive air through it and having a plurality of rows of moving blades whereof the first row has a hub tip ratio between 0·4 and 0·5; a high‐pressure axial flow compressor mounted in said casing, connected directly to said low‐pressure compressor to receive substantially the whole of the air compressed by said low‐pressure compressor and having a plurality of rows of moving blades; combustion equipment mounted in said casing and connected directly to said high‐pressure compressor to receive substantially the whole of the air compressed by said high‐pressure compressor; a single‐stage axial‐flow high‐pressure turbine mounted in said casing, connected directly to said combustion equipment to receive the products of combustion, and drivingly connected to said high‐pressure compressor, the power developed by said high‐pressure turbine being substantially wholly absorbed by said high‐pressure compressor; and a single‐stage axial‐flow low‐pressure turbine mounted in said casing, connected directly to said high‐pressure turbine to receive the exhaust from it and drivingly connected to said low‐pressure compressor, the power developed by said low‐pressure turbine being substantially wholly absorbed by said low‐pressure compressor; in which engine the ratio of the tip diameter of said low pressure turbine to the tip diameter of said first row of moving blades of said low pressure compressor is between 1 and 1·1; and the ratio between the power absorbed by the high‐pressure compressor and the power absorbed by the low‐pressure compressor is between 2 and 2·5 and the tip diameter of said first row of moving blades of said low pressure compressor is greater than the tip diameter of any other row of moving blades of either of said compressors, and the tip diameter of said low pressure turbine is greater than the tip diameter of said high pressure turbine.

Details

Aircraft Engineering and Aerospace Technology, vol. 28 no. 4
Type: Research Article
ISSN: 0002-2667

Article
Publication date: 15 September 2023

Zengli Wang, Qingyang Wang, Muming Hao, Xiaoying Li and Kewei Liu

The purpose of this study is to investigate the sealing performance of S-CO2 dry gas seals (DGSs) by considering the effects of pressure-induced deformation, thermal deformation…

Abstract

Purpose

The purpose of this study is to investigate the sealing performance of S-CO2 dry gas seals (DGSs) by considering the effects of pressure-induced deformation, thermal deformation and coupling deformation.

Design/methodology/approach

A hydrodynamic lubrication flow model of S-CO2 DGS was established, and the model was solved using the finite difference and finite element methods. The pressure-induced deformation and thermal deformation of the sealing ring, as well as the sealing performance under the effects of pressure-induced deformation, thermal deformation and coupling deformation, were obtained.

Findings

The deformation of the sealing ring is mainly thermal deformation. The influence of pressure-induced deformation on leakage and gas film stiffness is greater than that of thermal deformation and coupling deformation. However, thermal deformation has a greater impact on friction torque and minimum film thickness than pressure-induced deformation and coupling deformation. The influence of deformations on sealing performance is important.

Originality/value

The sealing performance of S-CO2 DGSs was analyzed considering the effect of pressure-induced deformation, thermal deformation and coupling deformation, which can provide a theoretical basis for S-CO2 DGS optimization design.

Peer review

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-04-2023-0120/

Details

Industrial Lubrication and Tribology, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 7 September 2023

Graeme Ditchburn and Rachel Evangeline Koh

COVID-19 forced organizations to implement protective measures changing how employees worked; however, empirical evidence is needed to explore how employees responded. This study…

Abstract

Purpose

COVID-19 forced organizations to implement protective measures changing how employees worked; however, empirical evidence is needed to explore how employees responded. This study examines the impact of COVID-19-related organizational changes in Singapore on employees’ perceptions of work pressure, stress and mental well-being (MWB) and the mediating role of resilience.

Design/methodology/approach

This study used a cross-sectional, anonymous online survey of 157 full-time employees who had worked for at least one year.

Findings

The results found that work pressure and stress had increased, and MWB had declined. Resilience acted as a buffer against increases in work pressure and stress while promoting the maintenance of MWB. Resilience significantly mediated the relationship between stress and MWB.

Research limitations/implications

The study does not allow for an assessment of causality but infers possible, albeit probable, casual relationships. Furthermore, stress and well-being could be influenced by a multitude of factors beyond organizational change. Future research should seek to account for additional factors and establish the generalisability of the findings beyond Singapore.

Practical implications

This study supports the engagement of resilience-based interventions to improve employees’ MWB during pandemic related organizational change.

Social implications

Policies that promote work-life balance, positive interpersonal relations and staying connected are some of the ways employers can bolster MWB and work-life balance to support employees who are engaged in remote work.

Originality/value

Given the unique context of COVID-19, this study allows for a better understanding of how a novel worldwide pandemic has transformed employees' experience of work and its associated impacts.

Details

Evidence-based HRM: a Global Forum for Empirical Scholarship, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2049-3983

Keywords

Article
Publication date: 12 September 2023

Jun-Hui Chai, Jun-Ping Zhong, Bo Xu, Zi-Jian Zhang, Zhengxiang Shen, Xiao-Long Zhang and Jian-Min Shen

The high-pressure accumulator has been widely used in the hydraulic system. Failure pressure prediction is crucial for the safe design and integrity assessment of the…

Abstract

Purpose

The high-pressure accumulator has been widely used in the hydraulic system. Failure pressure prediction is crucial for the safe design and integrity assessment of the accumulators. The purpose of this study is to accurately predict the burst pressure and location for the accumulator shells due to internal pressure.

Design/methodology/approach

This study concentrates the non-linear finite element simulation procedure, which allows determination of the burst pressure and crack location using extensive plastic straining criterion. Meanwhile, the full-scale hydraulic burst test and the analytical solution are conducted for comparative analysis.

Findings

A good agreement between predicted and measured the burst pressure that was obtained, and the predicted failure point coincided very well with the fracture location of the actual shell very well. Meanwhile, the burst pressure of the shells increases with wall thickness, independent of the length. It can be said that the non-linear finite element method can be employed to predict the failure behavior of a cylindrical shell with sufficient accuracy.

Originality/value

This paper can provide a designer with additional insight into how the pressurized hollow cylinder might fail, and the failure pressure has been predicted accurately with a minimum error below 1%, comparing the numerical results with experimental data.

Details

International Journal of Structural Integrity, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1757-9864

Keywords

Article
Publication date: 8 September 2023

Roel Boomsma

This paper aims to extend some of the theoretical propositions of Michael Power’s (1997) audit society thesis by exploring the capacity of organisations to push back against…

Abstract

Purpose

This paper aims to extend some of the theoretical propositions of Michael Power’s (1997) audit society thesis by exploring the capacity of organisations to push back against external accountability pressures. The paper positions the literature on non-governmental organisation (NGO) accounting and accountability as a “case study” against which the notion of the audit society is put to the test.

Design/methodology/approach

A qualitative meta-synthesis of the accounting literature is used to analyse how NGOs have responded to audit society pressures – most notably funder pressures to adopt formalised accountability mechanisms. The different responses of NGOs to funder accountability demands are analysed using Christine Oliver’s (1991) typology of strategic responses to institutional processes.

Findings

This review of the accounting literature unveils that NGOs can adopt a range of strategic responses to funder accountability pressures that vary from passive conformity to proactive manipulation. The findings confirm that NGOs often perceive acquiescence to funder accountability demands as necessary to ensure organisational survival. Yet, the author also found that NGO resistance to funder accountability pressures is more common than previously assumed. Five dominant forms of “accountability resistances” emerged from the analysis: evading accountability, disguising accountability, shielding accountability, negotiating accountability and shaping accountability.

Originality/value

By conducting a qualitative meta-synthesis of the accounting literature, the author was able to integrate the findings of prior research on NGO resistance to funder accountability demands, guide future research and extend Michael Power’s (1997) work by developing a more nuanced understanding of how organisations respond to external accountability pressures.

Details

Qualitative Research in Accounting & Management, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1176-6093

Keywords

Article
Publication date: 5 September 2023

Nasser Baharlou-Houreh, Navid Masaeli, Ebrahim Afshari and Kazem Mohammadzadeh

This paper aims to investigate the effect of partially blocking the cathode channel with the stair arrangement of obstacles on the performance of a proton exchange membrane fuel…

Abstract

Purpose

This paper aims to investigate the effect of partially blocking the cathode channel with the stair arrangement of obstacles on the performance of a proton exchange membrane fuel cell.

Design/methodology/approach

A numerical study is conducted by developing a three-dimensional computational fluid dynamics model.

Findings

As the angle of the stair arrangement increases, the performance of the fuel cell is reduced and the pressure drop is decreased. The use of four stair obstacles with an angle of 0.17° leads to higher power density and a lower pressure drop compared to the case with three rectangular obstacles of the same size and maximum height. The use of four stair obstacles with an angle of 0.34° results in higher power density and lower pressure drop compared to the case with two rectangular obstacles of the same size and maximum height.

Originality/value

Using the stair arrangement of obstacles as an innovation of the present work, in addition to improving the fuel cell’s performance, creates a lower pressure drop than the simple arrangement of obstacles.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 14 September 2023

Ankita Bedi and Balwinder Singh

The purpose of this paper is to seek to shed light on the influence of stakeholder pressure on carbon disclosure in an emerging economy.

Abstract

Purpose

The purpose of this paper is to seek to shed light on the influence of stakeholder pressure on carbon disclosure in an emerging economy.

Design/methodology/approach

The present study is based on Bombay Stock Exchange 100 Indian firms for the period of 5 years from 2016–17 to 2020–21. The association between stakeholder pressure and carbon disclosure, along with certain control variables, has been explored through a regression model.

Findings

The results of the study suggest that stakeholders exert a significant influence on corporate carbon disclosure. Further results confirm that regulatory and customer pressure have the most significant and positive influence, while shareholders and creditors exert a significant and negative influence on carbon disclosure. The study also finds that employee pressure does not have any association with carbon disclosure.

Practical implications

This study adds to the existing literature on climate change, carbon disclosure and stakeholder pressure.

Social implications

The present study provides useful insights to corporate managers and policymakers as the study concludes that stakeholders exert a significant influence on carbon disclosure.

Originality/value

Previous studies examining the stakeholder pressure on carbon disclosure ignored emerging economies, while the present study has considered India, which is a developing as well as an emerging economy. Further, to the best of the authors’ knowledge, the current study is the first of its kind to investigate the stakeholder pressure on carbon disclosure in the Indian context. The present study develops a comprehensive index to measure corporate carbon disclosure.

Details

Social Responsibility Journal, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1747-1117

Keywords

Article
Publication date: 20 December 2022

Shang-Han Gao and Sheng-Long Nong

The purpose of this paper is to derive the one-dimensional governing equations to describe the pressure distribution, load capacity and stiffness of aerostatic circular thrust…

66

Abstract

Purpose

The purpose of this paper is to derive the one-dimensional governing equations to describe the pressure distribution, load capacity and stiffness of aerostatic circular thrust bearing with a single air supply inlet.

Design/methodology/approach

The film flow field is divided into four regions: supply pressure region, pressure dropping region, pressure rising region and laminar flow region. The influences of bearing clearance and supply pressure on the pressure distribution, load capacity and stiffness of the bearing are presented.

Findings

With the large film clearance and large supply pressure, the oblique shock wave occurs near the entrance of gas film, which greatly increases the pressure drop region. Hence, it is not appropriate to consider the oblique shock as a normal shock.

Originality/value

This paper introduces the invariants at the entrance of gas film, employs the functional relationships between density and pressure, and provides the empirical formulas for the pressure dropping and rising regions. The pressure distribution curves are therefore illustrated through a considerably simplified computational process.

Details

Industrial Lubrication and Tribology, vol. 75 no. 2
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 30 August 2023

Jian Wei, XiaoYue Sun, Jing Tian and CaiHong Liu

This paper aims to study the impact of transient velocity changes on sealing performance during reciprocating sealing processes.

15

Abstract

Purpose

This paper aims to study the impact of transient velocity changes on sealing performance during reciprocating sealing processes.

Design/methodology/approach

Establish a model of transient mixed lubrication, solve the transient Reynolds equation, consider the effect of temperature rise at the seal interfaces, and determine the behavior of the seal interfaces, such as film thickness and fluid pressure. Evaluation with friction and leakage rate, calculate the variation of sealing performance with reciprocating velocity under different working conditions, and verify it through bench experiments.

Findings

Within a reciprocating stroke, the frictional force decreases with increasing velocity, and the frictional force of the outstroke is greater than that of the instroke; at the time of the stroke transition, the fluid pressure is smallest and the rough peak contact pressure is greatest. At present, the dynamic pressure effect of fluids is the largest, and the friction force also increases, which increases the risk of material wear and failure. Friction and leakage increase with increasing pressure and root mean square roughness. As temperature increases, friction increases and leakage decreases. In studying the performance variations of seal components through a reciprocating sealing experiment, it was found that the friction force decreases with increasing velocity, which is consistent with the calculated results and more similar to the calculated results considering the temperature rise.

Originality/value

This study provides a reference for the study of transient sealing performance.

Details

Industrial Lubrication and Tribology, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0036-8792

Keywords

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