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Article
Publication date: 3 June 2021

Masoud Behzad, Benjamin Herrmann, Williams R. Calderón-Muñoz, José M. Cardemil and Rodrigo Barraza

Volumetric air receivers experience high thermal stress as a consequence of the intense radiation flux they are exposed to when used for heat and/or power generation. This study…

Abstract

Purpose

Volumetric air receivers experience high thermal stress as a consequence of the intense radiation flux they are exposed to when used for heat and/or power generation. This study aims to propose a proper design that is required for the absorber and its holder to ensure efficient heat transfer between the fluid and solid phases and to avoid system failure due to thermal stress.

Design/methodology/approach

The design and modeling processes are applied to both the absorber and its holder. A multi-channel explicit geometry design and a discrete model is applied to the absorber to investigate the conjugate heat transfer and thermo-mechanical stress levels present in the steady-state condition. The discrete model is used to calibrate the initial state of the continuum model that is then used to investigate the transient operating states representing cloud-passing events.

Findings

The steady-state results constitute promising findings for operating the system at the desired airflow temperature of 700°C. In addition, we identified regions with high temperatures and high-stress values. Furthermore, the transient state model is capable of capturing the heat transfer and fluid dynamics phenomena, allowing the boundaries to be checked under normal operating conditions.

Originality/value

Thermal stress analysis of the absorber and the steady/transient-state thermal analysis of the absorber/holder were conducted. Steady-state heat transfer in the explicit model was used to calibrate the initial steady-state of the continuum model.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 32 no. 2
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 3 May 2019

Saeed Aghakhani, Behzad Ghasemi, Ahmad Hajatzadeh Pordanjani, Somchai Wongwises and Masoud Afrand

The purpose of this study is to conduct a numerical analysis of flow and heat transfer of water–aluminum oxide nanofluid in a channel with extended surfaces in the presence of a…

Abstract

Purpose

The purpose of this study is to conduct a numerical analysis of flow and heat transfer of water–aluminum oxide nanofluid in a channel with extended surfaces in the presence of a constant magnetic field. The channel consists of two parallel plates and five obstacles of constant temperature on the lower wall of the channel. The upper wall and the inlet and outlet lengths of the lower wall are insulated. A uniform magnetic field of the magnitude B0 is located beneath the obstacles. The nanofluid enters the channel with a uniform velocity and temperature, and a fully developed flow leaves the channel.

Design/methodology/approach

The control volume-based finite difference and the SIMPLE algorithm were used for numerical solution. In addition to examining the effect of the Reynolds number, the effects of Hartman number, the volume fraction of nanoparticles, the height of obstacles, the length of obstacles and the distance between the obstacles were investigated.

Findings

According to the results, the heat transfer rate increases with an increasing Reynolds number. As the Hartmann number increases, the heat transfer rate increases. The heat transfer rate also increases with an increase in the volume fraction of nanoparticles. The mean Nusselt number is reduced by an increasing height of obstacles. An increase in the distance between the obstacles in the presence of a magnetic field does not have a significant impact on the heat transfer rate. However, the heat transfer rate increases in the absence of a magnetic field, as the distance between the obstacles increases.

Originality/value

This paper is original and unpublished and is not being considered for publication elsewhere.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 29 no. 4
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 20 December 2018

Xiaohua Song and Yiming Shao

Modelling methods can be helpful for understanding vibrations of beam structures including cracks, as well as for early detection of crack. This study aims to provide an…

Abstract

Purpose

Modelling methods can be helpful for understanding vibrations of beam structures including cracks, as well as for early detection of crack. This study aims to provide an analytical modelling approach for a cantilever beam considering a slant vertical crack along its height. However, previous uniform crack methods cannot be used for describing this case. The results from the analytical, finite element (FE) and experimental methods are compared to verify the vibration problem.

Design/methodology/approach

A massless rotational spring model is adopted to describe the crack. An extended method based on the calculation method for a uniform vertical edge crack is proposed to obtain the stiffness of the slant case. The beam is divided into a series of independent thin slices along the beam height. An Euler–Bernoulli beam model is applied to formulate each slice. The crack in each slice is considered as a uniform one. The transfer matrix method in the literature is used to obtain the beam vibration frequencies and mode shapes. Influences of crack location and sizes on the natural frequencies for the cantilever beam, as well as the mode shapes, are analysed. An established FE model and test results in the listed references are used to validate the developed method.

Findings

The numerical results show that the rotational stiffness at the cracked section and the natural frequencies of the beam decrease by increasing the crack sizes; the natural frequencies for the beam are greatly influenced by the crack sizes and location; the first natural frequency decreases with the distance from the beam fixed end to the crack location; the value of the first natural frequency reaches a minimum value when the crack is at the beam fixed end; the value of the second natural frequency is a minimum value when the crack is at the beam middle; and the value of the third natural frequency is a minimum value when the crack is at the beam free end. Saltation is observed in some mode shapes at the crack location, especially for larger crack depths; but, the mode shapes of the beam are slightly influenced by the vertical crack.

Originality/value

This study gives a useful analytical modelling method for free vibration analysis for the cantilever beam with a vertical crack, which can overcome the disadvantages of the previous uniform crack methods.

Details

Engineering Computations, vol. 36 no. 1
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 20 March 2023

Esra Dobrucali, Emel Sadikoglu, Sevilay Demirkesen, Chengyi Zhang, Algan Tezel and Isik Ates Kiral

Construction is a risky industry. Therefore, organizations are seeking ways towards improving their safety performance. Among these, the integration of technology into health and…

1276

Abstract

Purpose

Construction is a risky industry. Therefore, organizations are seeking ways towards improving their safety performance. Among these, the integration of technology into health and safety leads to enhanced safety performance. Considering the benefits observed in using technology in safety, this study aims to explore digital technologies' use and potential benefits in construction health and safety.

Design/methodology/approach

An extensive bibliometrics analysis was conducted to reveal which technologies are at the forefront of others and how these technologies are used in safety operations. The study used two different databases, Web of Science (WoS) and Scopus, to scan the literature in a systemic way.

Findings

The systemic analysis of several studies showed that the digital technologies use in construction are still a niche theme and need more assessment. The study provided that sensors and wireless technology are of utmost importance in terms of construction safety. Moreover, the study revealed that artificial intelligence, machine learning, building information modeling (BIM), sensors and wireless technologies are trending technologies compared to unmanned aerial vehicles, serious games and the Internet of things. On the other hand, the study provided that the technologies are even more effective with integrated use like in the case of BIM and sensors or unmanned aerial vehicles. It was observed that the use of these technologies varies with respect to studies conducted in different countries. The study further revealed that the studies conducted on this topic are mostly published in some selected journals and international collaboration efforts in terms of researching the topic have been observed.

Originality/value

This study provides an extensive analysis of WoS and Scopus databases and an in-depth review of the use of digital technologies in construction safety. The review consists of the most recent studies showing the benefits of using such technologies and showing the usage on a systemic level from which both scientists and practitioners can benefit to devise new strategies in technology usage.

Details

Engineering, Construction and Architectural Management, vol. 31 no. 8
Type: Research Article
ISSN: 0969-9988

Keywords

Article
Publication date: 10 June 2021

Abbas Rajabifard, Masoud Kahalimoghadam, Elisa Lumantarna, Nilupa Herath, Felix Kin Peng Hui and Zahra Assarkhaniki

The achievement of the sustainable development goals (SDGs) for all communities and jurisdictions require a comprehensive roadmap that encompasses all dimensions of data…

1346

Abstract

Purpose

The achievement of the sustainable development goals (SDGs) for all communities and jurisdictions require a comprehensive roadmap that encompasses all dimensions of data infrastructure, social, economic, environmental and governance ecosystems. With this in mind, this paper aims to establish the link between the curriculum and intended learning outcomes of undergraduate and postgraduate subjects offered by the University and sustainability. This study is a part of a wider university strategy to embed sustainability knowledge and values in the university curricula. The 17 SDGs developed as a part of the 2030 Agenda for Sustainability Development was used as tool to measure and map how the subjects are linked with sustainability.

Design/methodology/approach

To incorporate sustainability into the curriculum, this paper developed an interdisciplinary approach for analysing the interconnection between the SDGs, the expected subject learning points and the relevant aspects of sustainability (geospatial information, the legal, policies and institutional components). As part of the approach, in the first phase of the study, qualitative data were collected through a review of published information on the SDGs and the content of the subjects available in the subject handbook. Subject codes were assigned to the keywords and key phrases extracted from the SDGs and the subject content, and then compared and matched to establish the link between the subjects and the SDGs. Six university schools offering over 2,157 subjects were investigated. In the second phase, a survey was conducted involving subject coordinators with the purpose of validating the findings of the first phase and determining the strength of the linkages between the subjects and the SDGs. In the third phase, a plugin was designed to be used in the digital twin platform developed in the UoM, allowing visualisation of the research outcomes.

Findings

Based on the interim findings, it was found that some subjects within the schools are linked to more than one SDG. However, not all of the subjects within the schools can be linked to the SDGs. There is a scope of improvement for embedding sustainability in more subjects within the schools. Some of the schools were also found to have weak linkages with sustainability, which demonstrate the challenge in technical subjects in linking their subject contents with sustainability.

Originality/value

This study provides a methodology which enables the integration of sustainability into current state of the curricula at the university to be established. Further, with the advancement of geospatial technology and new visualisation opportunities through the use of the digital twin platform provides capabilities to communicate the outcomes of sustainability and involvement of each faculties and departments more effectively to the university community and wider stakeholders.

Details

International Journal of Sustainability in Higher Education, vol. 22 no. 6
Type: Research Article
ISSN: 1467-6370

Keywords

Abstract

Details

Journal of Intelligent Manufacturing and Special Equipment, vol. 4 no. 1
Type: Research Article
ISSN: 2633-6596

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