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Article
Publication date: 25 January 2024

Chun Qiang Jia, Aofei Wang, Ling Yu and Li Zong

The rock drill’s drill tail experiences high-frequency fretting simultaneously in the rotational and axial directions. Due to the complex working characteristics and the low…

Abstract

Purpose

The rock drill’s drill tail experiences high-frequency fretting simultaneously in the rotational and axial directions. Due to the complex working characteristics and the low viscosity of the water medium, the pure water seal is susceptible to damage and failure. The purpose of this paper is to enhance the water seal’s performance.

Design/methodology/approach

The Y-shaped seal ring is modeled and simulated using orthogonal testing. Through analysis of the impact of various seal section parameters on sealing performance, the maximum contact stress and maximum Von Mises stress are selected as indicators of sealing effectiveness.

Findings

The maximum contact stress is proportional to lip thickness and chamfer length but inversely proportional to lip length. Meanwhile, the maximum Von Mises stress is directly influenced by lip depth and the included angle of the lip and drill tail but is inversely proportional to the lip thickness. The enhanced Y-shaped water seal sees reductions of 15% and 45% in maximum contact stress and maximum Von Mises stress, respectively.

Originality/value

This paper used analytical method and model that is helpful for design of the water seal’s structure in complex working characteristics and the low viscosity of the water medium.

Peer review

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-11-2023-0366/

Details

Industrial Lubrication and Tribology, vol. 76 no. 2
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 28 February 2024

Ahmed Jan, Muhammad F. Afzaal, Muhammad Mushtaq, Umer Farooq and Muzammil Hussain

This study investigates the flow and heat transfer in a magnetohydrodynamic (MHD) ternary hybrid nanofluid (HNF), considering the effects of viscous dissipation and radiation.

Abstract

Purpose

This study investigates the flow and heat transfer in a magnetohydrodynamic (MHD) ternary hybrid nanofluid (HNF), considering the effects of viscous dissipation and radiation.

Design/methodology/approach

The transport equations are transformed into nondimensional partial differential equations. The local nonsimilarity (LNS) technique is implemented to truncate nonsimilar dimensionless system. The LNS truncated equation can be treated as ordinary differential equations. The numerical results of the equation are accomplished through the implementation of the bvp4c solver, which leverages the fourth-order three-stage Lobatto IIIa formula as a finite difference scheme.

Findings

The findings of a comparative investigation carried out under diverse physical limitations demonstrate that ternary HNFs exhibit remarkably elevated thermal efficiency in contrast to conventional nanofluids.

Originality/value

The LNS approach (Mahesh et al., 2023; Khan et al., 20223; Farooq et al., 2023) that we have proposed is not currently being used to clarify the dynamical issue of HNF via porous media. The LNS method, in conjunction with the bvp4c up to its second truncation level, yields numerical solutions to nonlinear-coupled PDEs. Relevant results of the topic at hand, obtained by adjusting the appropriate parameters, are explained and shown visually via tables and diagrams.

Details

Multidiscipline Modeling in Materials and Structures, vol. 20 no. 2
Type: Research Article
ISSN: 1573-6105

Keywords

Open Access
Article
Publication date: 2 February 2023

Chiara Bertolin and Elena Sesana

The overall objective of this study is envisaged to provide decision makers with actionable insights and access to multi-risk maps for the most in-danger stave churches (SCs…

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Abstract

Purpose

The overall objective of this study is envisaged to provide decision makers with actionable insights and access to multi-risk maps for the most in-danger stave churches (SCs) among the existing 28 churches at high spatial resolution to better understand, reduce and mitigate single- and multi-risk. In addition, the present contribution aims to provide decision makers with some information to face the exacerbation of the risk caused by the expected climate change.

Design/methodology/approach

Material and data collection started with the consultation of the available literature related to: (1) SCs' conservation status, (2) available methodologies suitable in multi-hazard approach and (3) vulnerability leading indicators to consider when dealing with the impact of natural hazards specifically on immovable cultural heritage.

Findings

The paper contributes to a better understanding of place-based vulnerability with local mapping dimension also considering future threats posed by climate change. The results highlight the danger at which the SCs of Røldal, in case of floods, and of Ringebu, Torpo and Øye, in case of landslide, may face and stress the urgency of increasing awareness and preparedness on these potential hazards.

Originality/value

The contribution for the first time aims to homogeneously collect and report all together existing spread information on architectural features, conservation status and geographical attributes for the whole group of SCs by accompanying this information with as much as possible complete 2D sections collection from existing drawings and novel 3D drawn sketches created for this contribution. Then the paper contributes to a better understanding of place-based vulnerability with local mapping dimension also considering future threats posed by climate change. Then it highlights the danger of floods and landslides at which the 28 SCs are subjected. Finally it reports how these risks will change under the ongoing impact of climate change.

Details

International Journal of Building Pathology and Adaptation, vol. 42 no. 1
Type: Research Article
ISSN: 2398-4708

Keywords

Article
Publication date: 13 September 2022

Mohamed Nabil Houhou, Tamir Amari and Abderahim Belounar

This paper aims to investigate the responses of single piles and pile groups due to tunneling-induced ground movements in a two-layered soil system. The analyses mainly focus on…

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Abstract

Purpose

This paper aims to investigate the responses of single piles and pile groups due to tunneling-induced ground movements in a two-layered soil system. The analyses mainly focus on the additional single pile responses in terms of bending moment, lateral deflection, axial force, shaft resistance and pile settlement. Subsequently, a series of parametric studies were carried out to better understand the responses of single piles induced by tunneling. To give further understanding regarding the pile groups, a 2 × 2 pile group with two different pile head conditions, namely, free and capped, was considered.

Design/methodology/approach

Using the PLAXIS three-dimensional (3D) software, a full 3D numerical modeling is performed to investigate the effects of ground movements caused by tunneling on adjacent pile foundations. The numerical model was validated using centrifuge test data found in the literature. The relevance of the 3D model is also judged by comparison with the 2D plane strain model using the PLAXIS 2D code.

Findings

The numerical test results reveal that tunneling induces significant displacements and internal forces in nearby piles. The magnitude and distribution of internal forces depend mainly on the position of the pile toe relative to the tunnel depth and the distance between the pile and the vertical axis of the tunnel. As the volume loss increases from 1% to 3%, the apparent loss of pile capacity increases from 11% to 20%. By increasing the pile length from 0.5 to 1.5 times, the tunnel depth, the maximum pile settlement and lateral deflection decrease by about 63% and 18%, respectively. On the other hand, the maximum bending moment and axial load increase by about 7 and 13 times, respectively. When the pile is located at a distance of 2.5 times the tunnel diameter (Dt), the additional pile responses become insignificant. It was found that an increase in tunnel depth from 1.5Dt to 2.5Dt (with a pile length of 3Dt) increases the maximum lateral deflection by about 420%. Regarding the interaction between tunneling and group of piles, a positive group effect was observed with a significant reduction of the internal forces in rear piles. The maximum bending moment of the front piles was found to be higher than that of the rear piles by about 47%.

Originality/value

Soil is a complex material that shows differently in primary loading, unloading and reloading with stress-dependent stiffness. This general behavior was not possibly being accounted for in simple elastic perfectly plastic Mohr–Coulomb model which is often used to predict the behavior of soils. Thus, in the present study, the more advanced hardening soil model with small-strain stiffness (HSsmall) is used to model the non-linear stress–strain soil behavior. Moreover, unlike previous studies THAT are usually based on the assumption that the soil is homogeneous and using numerical methods by decoupled loadings under plane strain conditions; in this study, the pile responses have been exhaustively investigated in a two-layered soil system using a fully coupled 3D numerical analysis that takes into account the real interactions between tunneling and pile foundations. The paper presents a distinctive set of findings and insights that provide valuable guidance for the design and construction of shield tunnels passing through pile foundations.

Article
Publication date: 19 January 2024

Sobhan Pandit, Milan K. Mondal, Dipankar Sanyal, Nirmal K. Manna, Nirmalendu Biswas and Dipak Kumar Mandal

This study aims to undertake a comprehensive examination of heat transfer by convection in porous systems with top and bottom walls insulated and differently heated vertical walls…

Abstract

Purpose

This study aims to undertake a comprehensive examination of heat transfer by convection in porous systems with top and bottom walls insulated and differently heated vertical walls under a magnetic field. For a specific nanofluid, the study aims to bring out the effects of different segmental heating arrangements.

Design/methodology/approach

An existing in-house code based on the finite volume method has provided the numerical solution of the coupled nondimensional transport equations. Following a validation study, different explorations include the variations of Darcy–Rayleigh number (Ram = 10–104), Darcy number (Da = 10–5–10–1) segmented arrangements of heaters of identical total length, porosity index (ε = 0.1–1) and aspect ratio of the cavity (AR = 0.25–2) under Hartmann number (Ha = 10–70) and volume fraction of φ = 0.1% for the nanoparticles. In the analysis, there are major roles of the streamlines, isotherms and heatlines on the vertical mid-plane of the cavity and the profiles of the flow velocity and temperature on the central line of the section.

Findings

The finding of a monotonic rise in the heat transfer rate with an increase in Ram from 10 to 104 has prompted a further comparison of the rate at Ram equal to 104 with the total length of the heaters kept constant in all the cases. With respect to uniform heating of one entire wall, the study reveals a significant advantage of 246% rate enhancement from two equal heater segments placed centrally on opposite walls. This rate has emerged higher by 82% and 249%, respectively, with both the segments placed at the top and one at the bottom and one at the top. An increase in the number of centrally arranged heaters on each wall from one to five has yielded 286% rate enhancement. Changes in the ratio of the cavity height-to-length from 1.0 to 0.2 and 2 cause the rate to decrease by 50% and increase by 21%, respectively.

Research limitations/implications

Further research with additional parameters, geometries and configurations will consolidate the understanding. Experimental validation can complement the numerical simulations presented in this study.

Originality/value

This research contributes to the field by integrating segmented heating, magnetic fields and hybrid nanofluid in a porous flow domain, addressing existing research gaps. The findings provide valuable insights for enhancing thermal performance, and controlling heat transfer locally, and have implications for medical treatments, thermal management systems and related fields. The research opens up new possibilities for precise thermal management and offers directions for future investigations.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 34 no. 4
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 7 February 2024

Kai Cao, Guodong Qin, Jian Zhou, Jiajun Xu, Linsen Xu and Aihong Ji

With the popularity of high-rise buildings, wall inspection and cleaning are becoming more difficult and associated with danger. The best solution is to replace manual work with…

Abstract

Purpose

With the popularity of high-rise buildings, wall inspection and cleaning are becoming more difficult and associated with danger. The best solution is to replace manual work with wall-climbing robots. Therefore, this paper proposes a design method for a rolling-adsorption wall-climbing robot (RWCR) based on vacuum negative pressure adsorption of the crawler. It can improve the operation efficiency while solving the safety problems.

Design/methodology/approach

The pulleys and tracks are used to form a dynamic sealing chamber to improve the dynamic adsorption effect and motion flexibility of the RWCR. The mapping relationship between the critical minimum adsorption force required for RWCR downward slip, longitudinal tipping and lateral overturning conditions for tipping and the wall inclination angle is calculated using the ultimate force method. The pressure and gas flow rate distribution of the negative pressure chamber under different slit heights of the negative pressure mechanism is analysed by the fluid dynamics software to derive the minimum negative pressure value that the fan needs to provide.

Findings

Simulation and test results show that the load capacity of the RWCR can reach up to 6.2 kg on the smooth glass wall, and the maximum load in the case of lateral movement is 4.2 kg, which verifies the rationality and effectiveness of the design.

Originality/value

This paper presents a new design method of a RWCR for different rough wall surfaces and analyses the ultimate force state and hydrodynamic characteristics.

Details

Industrial Robot: the international journal of robotics research and application, vol. 51 no. 2
Type: Research Article
ISSN: 0143-991X

Keywords

Book part
Publication date: 31 January 2024

Eloise Labaz, Julie Nichols, Rebecca Agius and Quenten Agius

This chapter explores the Aboriginal artefacts ‘clapsticks’ as a form of cultural data – a means of disseminating cultural knowledge in the galleries, libraries, archives, and…

Abstract

This chapter explores the Aboriginal artefacts ‘clapsticks’ as a form of cultural data – a means of disseminating cultural knowledge in the galleries, libraries, archives, and museums [GLAM] sector. How might alternative methods of curation animate clapsticks as active objects that deliver effective knowledge transfer? This research aims to explore and extend current industry practices of the curation of clapsticks, within the existing parameters of technology, spatial capacity, financial support, and governance as part of the operation of the GLAM sector. The research problem, therefore, explores the past limitations of colonial framing of cultural institutions that once hindered the revealing, the disseminating, and the ‘awakening’ of the complexities of knowledge intrinsic to Aboriginal cultural artefacts. Informal communication with Aboriginal community members and academics was critical to providing cultural context as well as personal beliefs and aspirations vital to conceptualising the future of cultural representation. This investigation explores how a cultural centre offers a space and an opportunity to facilitate the clapsticks datasets in its capacity as a performance-focussed building rather than solely an exhibition space or keeping place. This potential represents a shift in thinking around the clapsticks being a lens through which the stories of Aboriginal culture can be disseminated.

Details

Data Curation and Information Systems Design from Australasia: Implications for Cataloguing of Vernacular Knowledge in Galleries, Libraries, Archives, and Museums
Type: Book
ISBN: 978-1-80455-615-3

Keywords

Article
Publication date: 25 March 2024

Boyang Hu, Ling Weng, Kaile Liu, Yang Liu, Zhuolin Li and Yuxin Chen

Gesture recognition plays an important role in many fields such as human–computer interaction, medical rehabilitation, virtual and augmented reality. Gesture recognition using…

Abstract

Purpose

Gesture recognition plays an important role in many fields such as human–computer interaction, medical rehabilitation, virtual and augmented reality. Gesture recognition using wearable devices is a common and effective recognition method. This study aims to combine the inverse magnetostrictive effect and tunneling magnetoresistance effect and proposes a novel wearable sensing glove applied in the field of gesture recognition.

Design/methodology/approach

A magnetostrictive sensing glove with function of gesture recognition is proposed based on Fe-Ni alloy, tunneling magnetoresistive elements, Agilus30 base and square permanent magnets. The sensing glove consists of five sensing units to measure the bending angle of each finger joint. The optimal structure of the sensing units is determined through experimentation and simulation. The output voltage model of the sensing units is established, and the output characteristics of the sensing units are tested by the experimental platform. Fifteen gestures are selected for recognition, and the corresponding output voltages are collected to construct the data set and the data is processed using Back Propagation Neural Network.

Findings

The sensing units can detect the change in the bending angle of finger joints from 0 to 105 degrees and a maximum error of 4.69% between the experimental and theoretical values. The average recognition accuracy of Back Propagation Neural Network is 97.53% for 15 gestures.

Research limitations/implications

The sensing glove can only recognize static gestures at present, and further research is still needed to recognize dynamic gestures.

Practical implications

A new approach to gesture recognition using wearable devices.

Social implications

This study has a broad application prospect in the field of human–computer interaction.

Originality/value

The sensing glove can collect voltage signals under different gestures to realize the recognition of different gestures with good repeatability, which has a broad application prospect in the field of human–computer interaction.

Details

Sensor Review, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0260-2288

Keywords

Open Access
Article
Publication date: 8 November 2022

Jacob Mhlanga, Theodore C. Haupt and Claudia Loggia

This paper aims to explore the intellectual structure shaping the circular economy (CE) discourse within the built environment in Africa.

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Abstract

Purpose

This paper aims to explore the intellectual structure shaping the circular economy (CE) discourse within the built environment in Africa.

Design/methodology/approach

The study adopted a bibliometric analysis approach to explore the intellectual structure of CE in the built environment in Africa. The authors collected 31 papers published between 2005 and 2021 from the Scopus database and used VOSviewer for data analysis.

Findings

The findings show that there are six clusters shaping the intellectual structure: demolition, material recovery and reuse; waste as a resource; cellulose and agro-based materials; resilience and low-carbon footprint; recycling materials; and the fourth industrial revolution. The two most cited scholars had three publications each, while the top journal was Resources, Conservation and Recycling. The dominant concepts included CE, sustainability, alternative materials, waste management, lifecycle, demolition and climate change. The study concludes that there is low CE research output in Africa, which implies that the concept is either novel or facing resistance.

Research limitations/implications

The data were drawn from one database, Scopus; hence, adoption of alternative databases such as Web of Science, Google Scholar and Dimensions could potentially have yielded a higher number of articles for analysis which potentially would result in different conclusions on the subject understudy.

Originality/value

This study made a significant contribution by articulating the CE intellectual structure in the built environment, identified prominent scholars and academic platforms responsible for promoting circularity in Africa.

Details

Journal of Engineering, Design and Technology , vol. 22 no. 2
Type: Research Article
ISSN: 1726-0531

Keywords

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