Ehsan Bazarchi, Yousef Hosseinzadeh and Parinaz Panjebashi Aghdam
It is common practice in structural engineering to assume floor diaphragms infinitely stiff in their own plane. But, most of the code provisions lack clarity and unity in…
Abstract
Purpose
It is common practice in structural engineering to assume floor diaphragms infinitely stiff in their own plane. But, most of the code provisions lack clarity and unity in categorising floor diaphragms and discussing their behaviour based on the seismic response of the structures. Besides, although many of these code provisions have presented simple techniques and formulations for determining the level of flexibility in floor diaphragms, the implementation of these techniques on more complex floor systems such as the steel-deck composite floors is still under question. The paper aims to discuss these issues.
Design/methodology/approach
In this study, an equivalent concrete floor is employed as a representative of in-plane diaphragm action of steel-deck composite floor, using simple modelling techniques in SAP2000 and the results are validated by complex structural models developed in ABAQUS. Afterwards, the equivalent floor is inserted to 3, 5 and 7 storey steel structures with 2, 3 and 5 plan aspect ratios in two categories of structures with rigid diaphragms and analogous structures with flexible diaphragms and the responses are compared to each other.
Findings
The results show that the proposed technique is an effective method for evaluating the diaphragm action of steel-deck composite floors. Additionally, it is concluded that, the boundary values of plan aspect ratio equal to 3 and λ coefficient equal to 0.5 in steel-deck composite floors, mentioned in code provisions for categorising diaphragms, are not always conservative and need to be scrutinised.
Originality/value
The proposed methodology provides simple framework for assessing the effects of in-plane flexibility of steel-deck composite on seismic response of steel structures.
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S. Hoseinzadeh, S.M. Taheri Otaghsara, M.H. Zakeri Khatir and P.S. Heyns
The purpose of this study is to investigate the pulsating flow in a three-dimensional channel. Channel flow is laminar and turbulent. After validation, the effect of different…
Abstract
Purpose
The purpose of this study is to investigate the pulsating flow in a three-dimensional channel. Channel flow is laminar and turbulent. After validation, the effect of different channel cross-sectional geometries (circular, hexagonal and triangular) with the pulsating flow are investigated. For this purpose, the alumina nanofluid was considered as a working fluid with different volume percentages (0 per cent [pure water], 3 per cent and 5 per cent).
Design/methodology/approach
In this study, the pulsatile flow was investigated in a three-dimensional channel. Channel flow is laminar and turbulent.
Findings
The results show that the fluid temperature decreases by increasing the volume percentage of particles of Al2O3; this is because of the fact that the input energy through the wall boundary is a constant value and indicates that with increasing the volume percentage, the fluid can save more energy at a constant temperature. And by adding Al2O3 nanofluid, thermal performance improves in channels, but it should be considered that the use of nanofluid causes a pressure drop in the channel.
Originality/value
Alumina/water nanofluid with the pulsating flow was investigated and compared in three different cross-sectional channel geometries (circular, hexagonal and triangular). The effect of different volume percentages (0 per cent [pure water], 3 per cent and 5 per cent) of Al2O3 nanofluid on temperature, velocity and pressure are studied.
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S. Hoseinzadeh, P.S. Heyns and H. Kariman
The purpose of this paper is to investigate the heat transfer of laminar and turbulent pulsating Al203/water nanofluid flow in a two-dimensional channel. In the laminar flow…
Abstract
Purpose
The purpose of this paper is to investigate the heat transfer of laminar and turbulent pulsating Al203/water nanofluid flow in a two-dimensional channel. In the laminar flow range, with increasing Reynolds number (Re), the velocity gradient is increased. Also, the Nusselt number (Nu) is increased, which causes increase in the overall heat transfer rate. Additionally, in the change of flow regime from laminar to turbulent, average thermal flux and pulsation range are increased. Also, the effect of different percentage of Al2O3/water nanofluid is investigated. The results show that the addition of nanofluids improve thermal performance in channel, but the using of nanofluid causes a pressure drop in the channel.
Design/methodology/approach
The pulsatile flow and heat transfer in a two-dimensional channel were investigated.
Findings
The numerical results show that the Al2O3/Water nanofluid has a significant effect on the thermal properties of the different flows (laminar and turbulent) and the average thermal flux and pulsation ranges are increased in the change of flow regime from laminar to turbulent. Also, the addition of nanofluid improves thermal performance in channels.
Originality/value
The originality of this work lies in proposing a numerical analysis of heat transfer of pulsating Al2O3/Water nanofluid flow -with different percentages- in the two-dimensional channel while the flow regime change from laminar to turbulent.
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Sami Ul Haq, Muhammad Bilal Ashraf and Arooj Tanveer
The main focus is to provide a non-similar solution for the magnetohydrodynamic (MHD) flow of Casson fluid over a curved stretching surface through the novel technique of the…
Abstract
Purpose
The main focus is to provide a non-similar solution for the magnetohydrodynamic (MHD) flow of Casson fluid over a curved stretching surface through the novel technique of the artificial intelligence (AI)-based Lavenberg–Marquardt scheme of an artificial neural network (ANN). The effects of joule heating, viscous dissipation and non-linear thermal radiation are discussed in relation to the thermal behavior of Casson fluid.
Design/methodology/approach
The non-linear coupled boundary layer equations are transformed into a non-linear dimensionless Partial Differential Equation (PDE) by using a non-similar transformation. The local non-similar technique is utilized to truncate the non-similar dimensionless system up to 2nd order, which is treated as coupled ordinary differential equations (ODEs). The coupled system of ODEs is solved numerically via bvp4c. The data sets are constructed numerically and then implemented by the ANN.
Findings
The results indicate that the non-linear radiation parameter increases the fluid temperature. The Casson parameter reduces the fluid velocity as well as the temperature. The mean squared error (MSE), regression plot, error histogram, error analysis of skin friction, and local Nusselt number are presented. Furthermore, the regression values of skin friction and local Nusselt number are obtained as 0.99993 and 0.99997, respectively. The ANN predicted values of skin friction and the local Nusselt number show stability and convergence with high accuracy.
Originality/value
AI-based ANNs have not been applied to non-similar solutions of curved stretching surfaces with Casson fluid model, with viscous dissipation. Moreover, the authors of this study employed Levenberg–Marquardt supervised learning to investigate the non-similar solution of the MHD Casson fluid model over a curved stretching surface with non-linear thermal radiation and joule heating. The governing boundary layer equations are transformed into a non-linear, dimensionless PDE by using a non-similar transformation. The local non-similar technique is utilized to truncate the non-similar dimensionless system up to 2nd order, which is treated as coupled ODEs. The coupled system of ODEs is solved numerically via bvp4c. The data sets are constructed numerically and then implemented by the ANN.
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S. Hoseinzadeh, Ali Sohani, Saman Samiezadeh, H. Kariman and M.H. Ghasemi
This study aim to use the finite volume method to solve differential equations related to three-dimensional simulation of a solar collector. Modeling is done using ANSYS-fluent…
Abstract
Purpose
This study aim to use the finite volume method to solve differential equations related to three-dimensional simulation of a solar collector. Modeling is done using ANSYS-fluent software program. The investigation is done for a photovoltaic (PV) solar cell, with the dimension of 394 × 84 mm2, which is the aluminum type and receives the constant heat flux of 800 W.m−2. Water is also used as the working fluid, and the Reynolds number is 500.
Design/methodology/approach
In the present study, the effect of fluid flow path on the thermal, electrical and fluid flow characteristics of a PV thermal (PVT) collector is investigated. Three alternatives for flow paths, namely, direct, curved and spiral for coolant flow, are considered, and a numerical model to simulate the system performance is developed.
Findings
The results show that the highest efficiency is achieved by the solar cell with a curved fluid flow path. Additionally, it is found that the curved path’s efficiency is 0.8% and 0.5% higher than that of direct and spiral paths, respectively. Moreover, the highest pressure drop occurs in the curved microchannel route, with around 260 kPa, which is 2% and 5% more than the pressure drop of spiral and direct.
Originality/value
To the best of the authors’ knowledge, there has been no study that investigates numerically heat transfer, fluid flow and electrical performance of a PV solar thermal cell, simultaneously. Moreover, the effect of the microchannel routes which are considered for water flow has not been considered by researchers so far. Taking all the mentioned points into account, in this study, numerical analysis on the effect of different microchannel paths on the performance of a PVT solar collector is carried. The investigation is conducted for the Reynolds number of 500.
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T. Barbaryan, S. Hoseinzadeh, P.S. Heyns and M.S. Barbaryan
This study aims to develop a new design for the fluid-safety valve to make it more environmentally friendly.
Abstract
Purpose
This study aims to develop a new design for the fluid-safety valve to make it more environmentally friendly.
Design/methodology/approach
Computational fluid dynamics is carried out to analyse the behaviour of flow in both traditional and new safety valves.
Findings
The possibility of failure in the new design under the maximum allowable working pressure is analysed using finite element analysis.
Originality/value
Investigating a new low-fluid pressure safety valve design.
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Deepesh Sharma and Naresh Kumar Yadav
In computer application scenario, data mining task is rarely utilized in power system, as an enhanced part, this work presented data mining task in power systems, to overcome…
Abstract
Purpose
In computer application scenario, data mining task is rarely utilized in power system, as an enhanced part, this work presented data mining task in power systems, to overcome frequency deviation issues. Load frequency control (LFC) is a primary challenging problem in an interconnected multi-area power system.
Design/methodology/approach
This paper adopts lion algorithm (LA) for the LFC of two area multi-source interconnected power systems. The LA calculates the optimal gains of the fractional order PI (FOPI) controller and hence the proposed LA-based FOPI controller (LFOPI) is developed.
Findings
For the performance analysis, the proposed algorithm compared with various algorithm is given as, 80.6% lesser than the FOPI algorithm, 2.5% lesser than the GWO algorithm, 2.5% lesser than the HSA algorithm, 4.7% lesser than the BBO algorithm, 1.6% lesser than PSO algorithm and 80.6% lesser than the GA algorithm.
Originality/value
The LFOPI controller is the proposed controlling method, which is nothing but the FOPI controller that gets the optimal gain using the LA. This method produces better performance in terms of converging behavior, optimization of controller gain, transient profile and steady-state response.
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Izra Berakon, Amin Wibowo, Nurul Indarti, Nor Nabilla Muhammad and Rizaldi Yusfiarto
The purpose of this study is to examine the effect of the efficiency model on firms performance. The authors also strive to test the compatibility of the efficiency models of…
Abstract
Purpose
The purpose of this study is to examine the effect of the efficiency model on firms performance. The authors also strive to test the compatibility of the efficiency models of Sharia and non-Sharia manufacturing firms.
Design/methodology/approach
The samples are manufacturing industry firms listed on the Indonesia Stock Exchange from 2013 to 2021. This study used 68 firms, with details of 34 Sharia while the remaining 34 were non-Sharia. The data were analyzed using generalized least square (GLS) to test the entire formulated hypothesis. Moreover, current research provides robustness tests to gain more valid and reliable results.
Findings
The results demonstrated that cost efficiency (CE), human capital efficiency (HCE) and capital intensity (CI) affect the firm’s performance. The efficiency model is more appropriate to be applied to the manufacturing Sharia firms in Indonesia. The results are robust even though the feasible GLS and panel-corrected standards errors models are added and a split sample is applied based on certain firm characteristics.
Practical implications
This research can bridge the theory and practice that exist in companies. The authors proposed an efficiency model that can maximize firm performance profits. Moreover, it turns out that the efficiency model is more relevant to be applied to Sharia firms in Indonesia. Furthermore, the research findings have several implications notably for theoretical development, global enterprises and practitioners.
Originality/value
This study expands the literature and discussion about the efficiency model by formulating and investigating CE, HCE and CI on the firm performance which previous studies have rarely elaborated on and tested. In addition, the authors divided the sample into two groups (Sharia and non-Sharia firms) to ensure the compatibility of the implementation of the efficiency model on firm performance.