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The purpose of this paper is to determine the effects of environmental factors in open-plan offices with the same characteristics but with different workstation partition heights (1.10, 1.40 and 1.65 m) on perceptual evaluations of office employees.

In this research, the effects of environmental factors on employees’ perceptual evaluations in open-plan offices at the Gölbaşı Region of Ankara were measured with a detailed questionnaire. The research data were obtained from 81 employees who agreed to fill out the questionnaire and who use open-plan offices.

It was found that the office environments with 1.65 m workstation partition heights were more favorably assessed for each of the items of planning and of privacy that form the dependent variables compared to the office environments with 1.10  and 1.40 m partition heights. On the other hand, the office environments with the 1.10 and 1.40 m partition heights were more favorable for lighting items than the 1.65 m partition height office environments. In addition, young employees had a more positive tendency toward the perceptions of environmental factors, including different workstation partition heights in open-plan offices, compared to older employees.

Results of this research provide a fundamental contribution for the impact of various partition heights that have substantial implications on the perceptions of open-plan office environments. At this point, as open-plan offices have important effects on the quality of employees’ work experiences, the influence of various partition heights on the performance of employees should be emphasized in future studies. The diversity of performance (reading comprehension, calculation, design, drawing, etc.) will be an important decision.

The significant contribution of this research is that it provides valid data and makes a valuable contribution to the body of knowledge in open-plan office design.

This paper aims to numerically examine the mixed convection of SiO₂-water nanofluid flow in a three-dimensional (3D) cubic cavity with a conductive partition considering various shapes of the particles (spherical, cylindrical, blade, brick). The purpose is to analyze the effects of various pertinent parameters such as Richardson number (between 0.1 and 10), Hartmann number (between 0 and 10), solid nanoparticle volume fraction (between 0 and 0.04), particle shape (spherical, cylindrical, blade, brick) and different heights and lengths of the conductive partition on the fluid flow and heat transfer characteristics.

The numerical simulation was performed by using Galerkin-weighted residual finite element method for various values of Richardson number, Hartmann number, solid nanoparticle volume fraction, particle shape (spherical, cylindrical, blade, brick) and different heights and lengths of the conductive partition. Two models for the average Nusselt number were proposed for nanofluids with spherical and cylindrical particle by using multi-layer feed-forward neural networks.

It was observed that the average Nusselt number reduces for higher values of Richardson number and Hartmann number, while enhances for higher values of nanoparticle volume fraction. Among various types of particle shapes, blade ones perform the worst and cylindrical ones perform the best in terms of heat transfer enhancement, but this is not significant which is less than 3 per cent. The average Nusselt number deteriorates by about 6.53per cent for nanofluid at the highest volume fraction of spherical particle shapes, but it is 11.75per cent for the base fluid when Hartmann number is increased from 0 to 10. Conductive partition geometrical parameters (length and height) do not contribute to much to heat transfer process for the 3D cavity, except for the case when height of the partition reaches 0.8 times the height of the cubic cavity, the average Nusselt number value reduces by about 25per cent both for base fluid and for nanofluid when compared to case with cavity height which is 0.2 times the height of the cubic cavity.

Based on the literature survey, a 3D configuration for MHD mixed convection of nanofluid flow in a cavity with a conductive partition considering the effects of various particle shapes has never been studied in the literature. This study is a first attempt to use a conductive partition with nanofluid of various particle shapes to affect the fluid flow and heat transfer characteristics in a 3D cubic cavity under the influence of magnetic field. Partial or all findings of this study could be used for the design and optimization of realistic 3D thermal configurations that are encountered in practice and some of the applications were already mentioned above. In this study, thermal performance of the system was obtained in terms of average heat transfer coefficient along the hot surface, and it is modeled with multi-layer feed-forward neural networks.

The heat transfer by radiation and natural convection in a two‐dimensional, air‐filled square enclosure with a vertical partition of finite thickness and varying height was investigated numerically in the laminar regime. The horizontal end walls are assumed to be adiabatic, and the vertical walls are at different temperatures. Calculations are made by using a finite volume method and an efficient numerical procedure is introduced for calculating the view factors, with shadow effects included. The results indicate that the partition does not significantly modify the heat transfer rate through the cavity, especially at high Rayleigh numbers, provided that its height is less than 90 per cent of the cavity height. The effects of radiation on the velocity and the temperature fields and the overall heat transfer rates as a function of the widths of the vents, solid/fluid conductivity ratio and Rayleigh number are documented.

The purpose of this paper is to describe the development and employment of an hp‐adaptive finite element method (FEM) algorithm for solving heat transfer problems in partitioned enclosures, which has attracted the attention of both experimental and theoretical researchers in recent years.

In the hp‐adaptive FEM algorithm presented here, both the element size and the shape function order are dynamically controlled by an a posteriori error estimator based on the L₂ norm; a three‐step adaptation strategy is used with a projection algorithm for the flow solver.

Simulation results are obtained for 2D and 3D natural convection within partitioned enclosures. Results show refined and enriched elements that develop near the partition edges and side walls of the enclosure, as expected. The heat transfer between the heated and cooled side walls is reduced in the presence of a partial partition.

The Rayleigh numbers were set to 10⁵ in the 2D case and 10³ in the 3D case. Efforts are underway to apply the hp‐adaptive algorithm to partitioned enclosures at much higher Rayleigh numbers, including comparison with available experimental data.

Heat transfer within partitioned enclosures occurs in many engineering situations: heat transfer across thermo pane windows, solar collectors, fire spread and energy transfer in rooms and buildings, cooling of nuclear reactors and heat exchanger design.

The hp‐adaptive FEM algorithm is one of the best mesh‐based algorithms for improving solution quality, whilst maintaining computational efficiency. The method shows considerable promise in solving a wide range of heat transfer problems including fluid flow.

The purpose of this paper is to provide a solution for natural convection in a cavity with a partial heater in case of volumetric heating and analysis of the entropy generation.

The control volume method based on three-dimensional (3D) vorticity-potential vector was applied to solve governing equations of natural convection in a 3D cavity with a fin for different governing parameters as external Rayleigh numbers (103=Ra_E=106), internal Rayleigh numbers 103=Ra_I=106, partition height (0.25=h=0.75) and partition location (0.25=c=0.75). A code was written by using Fortran platform.

The edge of the fin becomes important on entropy generation. The ratio of the Ra_I/Ra_E plays the important role on natural convection and entropy generation. The variation of external Rayleigh number becomes insignificant for the Ra_I/Ra_E>1.

The originality of this work is to analyze the entropy generation and natural convection in a cubical cavity with volumetrically heating.

This paper seeks to investigate the effect of a heat conducting vertical partition in an enclosure on natural convection heat transfer and fluid flow using the polynomial‐based differential quadrature (PDQ) method.

The PDQ method with the non‐uniform Chebyshev‐Gauss‐Lobatto grid point distribution given below is used to transform the governing equations into a set of algebraic equations. After numerical discretization, the resulting algebraic equations are solved by the successive over‐relaxation iteration method.

It is found that the average Nusselt number decreases towards a constant value as the partition is distanced from the hot wall towards the middle of the enclosure. Furthermore, with decreasing thermal conductivity ratio, the average Nusselt number first increases and passes a peak point and then begins to decrease. The average heat transfer rate exhibits little dependence on the width of the partition in the range taken into consideration in this study for the thickness of the partition.

This study offers more knowledge on natural convection in partitioned enclosures.

The purpose of this paper is to propose an applicable solution to help organizations to solve the problem of participation vs privacy in office buildings.

A theoretical model is proposed based on research claims that employees' participation motivated by three issues simultaneously is likely to shape the ideal overall participation map in office layouts. These are organizational, physical planning, and personal characteristics issues. The model was applied to a case study and results were compared with employees' reaction.

Once the model was applied, results revealed misallocation of 63 per cent of staff in their workspaces. Results support employees' reaction towards their dissatisfaction with the level of participation vs privacy they possess in their workspaces.

Each organization could have a different participation map due to variations in organizational and personal characteristics issues. Further research is needed to understand relationships among the three incorporated issues.

The proposed model could be easily applied and would provide organizations with ideal office layouts that would support productivity.

This paper sets out to understand the impact of the ambient environment on perceived comfort, health, wellbeing and by extension productivity in the workplace.

The research combined an occupant survey considering satisfaction with the ambient environment, health and wellbeing and workplace behaviour with the monitoring of ambient environmental conditions.

The paper demonstrates that the ambient environment can have a significant impact on occupant comfort, health and wellbeing, which in turn has implications for built asset performance. Within the ambient environmental factors considered, a hierarchy may exist with noise being of particular importance. Occupant behaviour within the workplace was also found to be influential.

The research was limited to a single commercial office building, and a wider range of case studies would therefore be of benefit. The research was also limited to the summer months.

The findings show that an active approach to asset management is required, by continuously monitoring internal environment and engaging with occupants. This must carefully consider how ambient environmental factors and workplace behaviour impact upon occupants’ comfort, health and wellbeing to ensure the performance of the built asset is maximised.

This paper demonstrates that both occupiers’ workplace behaviour and ambient environmental conditions can have an impact on occupant comfort, health, wellbeing and productivity. The paper strengthens the case for the active management of the workplace environment through environmental monitoring and behaviour change campaigns supported by corresponding changes to workplace culture.

The growing need for cellularisation presents the facilities manager with an array of partitioning options that can be daunting. Patrick Manwell, of Phippen, Randall and Parkes, looks at proprietary products available and at the principles that underpin their construction.

This paper aims to determine the extent to which employees’ experiences of acoustic comfort, well-being and productivity in open-plan offices are determined by specific characteristics (including demographic information, task characteristics, and personality traits).

A questionnaire was distributed to the occupants of three open-plan office sites and was completed by 166 employees in total.

The results indicated that acoustic comfort in open-plan offices is largely determined by noise sensitivity. Higher noise sensitivity was associated with more negative ratings of acoustical quality, more perceived disturbance by speech and more difficulties in concentration. More negative experiences were also reported by employees with lower interactivity with colleagues.

There is significant inter-individual variability in experiences of acoustic comfort, well-being and productivity in open-plan offices. As such, workplace practitioners should consider acoustic and behavioural solutions for introducing a greater diversity of functional workspaces within the office, so that employees can choose the most suitable working area for their requirements.

Whereas the majority of past acoustics research has been laboratory-based, this study is conducted in real office environments with a representative sample of knowledge workers.