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The sensitivity of orifice plate metering to poorly conditioned and swirling flows are subjects of concerns to flow meter users and manufacturers. The distortions caused by pipe fittings and pipe installations upstream of the orifice plate are major sources of this type of non‐standard flows. These distortions will alter the accuracy of metering up to an unacceptable degree.Design/methodology/approach – The design of orifice plate meters that are independent of the initial flow conditions of the upstream is a major object of flow metering. Either using a long straight pipe or a flow conditioner upstream of an orifice plate usually achieves this goal. The effect of cone swirler flow conditioner for both standard and non‐standard flow conditions has been carried out in the experimental rig. The measuring of mass flow rate under different conditions and different Reynolds numbers were used to establish a change in discharge coefficient relative to a standard one.Findings – The experimental results using the cone swirler flow conditioner showed that the combination of an orifice plate and cone swirler flow conditioner is broadly insensitive to upstream disturbances. The results clearly show that this flow conditioner can attenuate the effect of both swirling and asymmetric flows on metering to an acceptable level.Originality/value – Previous work on the orifice plate has shown that the concept has promise. The results of using a combination of a cone swirler and orifice plate for non‐standard flow conditions including swirling flow and asymmetric flow show this package can preserve the accuracy of metering up to the level required in the standards, providing that a new discharge coefficient is used for the combined swirler and orifice plate.

The Greenery system on buildings is an interesting approach to address the urban, and environmental issues yet provide economic and social benefits. The educational campus in Higher Learning Institution (HLI) has been regarded as a small city that can implement the greenery system area. Green roofs have rapidly become a key in sustainable building development and design features for urban cities and have started being applied in a campus building. However, the built environment in the campus is mostly covered with the existing buildings. Several studies also conducted green roof aspects but with a vast focus on the new building design. Thus, there is an urgent need to identify retrofitting criteria on green roof implementation for existing buildings to achieve optimal solutions. This chapter aims to identify the influential criteria for implementing green roof initiatives in the educational building of HLI. A list of 12 green roof criteria has been identified based on design and economics. A questionnaire has been designed and distributed to architects as important stakeholders in green roof development. The results obtained were analysed with factor analysis based on principal component analysis with Varimax Rotation and Factor Score to categorise and rank according to the importance of criteria. The outcomes of this study showed that design criteria should concern waterproofing, drainage, and access; economic criteria are construction costs, return on investment, and maintenance cost. This study enables decision-makers to consider the criteria established during the decision of retrofitting an existing building with a green roof.

A detailed numerical study is conducted on the effect of surface radiation on laminar natural convection in a tall vertical cavity filled with air. The cavity is heated and cooled, through its two vertical walls, by a linear or uniform heat flux q(y) and by a constant cold temperature, respectively. The horizontal walls are considered adiabatic. The paper aims to discuss these issues.

The radiosity method is employed to calculate the net radiative heat exchanges between elementary surfaces, while the finite volume method is implemented to resolve the governing equations of the fluid flow.

For each heat flux q(y) (ascending, descending or uniform), the effect of the emissivity ε (0ε1) on the local, average and maximum temperatures of the heated wall is determined as a function of the average Rayleigh number Ra_m (103Ra_m 6×104) and the cavity aspect ratio A (10A80). The effect of the coupling on the flow structures, convective and radiative heat transfers is also presented and analyzed. Overall, it is shown that surface radiation significantly reduces the local and average temperatures of the heated wall and therefore reduces the convective heat transfer between the active walls.

The studied configuration is of practical interest in several areas where overheating must be avoided. For this purpose, a simple design tool is developed to estimate the mean and the maximum temperatures of the hot wall in different operating conditions (Ra_m, A et ε).

The originality lies in the study of the interaction between surface radiation and natural convection in tall cavities submitted to a non-uniform heat flux and a constant cold temperature on the active walls. Also, the development of an original simplified calculation procedure for the hot wall temperatures.

The study aims to underscore the initiatives taken by the Gulf Cooperation Council (GCC) countries in spearheading their drive towards creating “smart” cities.

The study uses a qualitative approach by invoking documentary analysis supplemented by responses provided by 13 interviewees from public and private sector.

All the six GCC countries (Bahrain, Kuwait, Oman, Qatar, Saudi Arabia and United Arab Emirates) are keen on building upon their infrastructure to push their “smart city” agenda which would go a long way in furthering the economic diversification objective of their region besides improving the quality of public services.

Hitherto, research has been focused on appreciating the “smart city” initiatives of developed countries; this study seeks to build upon the literature on “smart cities” by contextualizing the research setting in the developing countries. Second, the study shows that with the ongoing oil prices crisis in the GCC, the “smart city” initiatives of the countries are conceived as possible avenues of economic diversification and competitiveness.

On the basis of corporate wholesale and hypermarket stores, this study aims to investigate the relationship between energy consumption, physical building characteristics and operational sales performance and the impact of energy management on the corporate environmental performance.

A very unique dataset of METRO GROUP over 19 European countries is analyzed in a sophisticated econometric approach for the timeframe from January 2011 until December 2014. Multiple regression models are applied for the panel, to explain the electricity consumption of the corporate assets on a monthly basis and the total energy consumption on an annual basis. Using Generalized Additive Models, to model nonlinear covariate effects, the authors decompose the response variables into the implicit contribution of building characteristics, operational sales performance and energy management attributes, under control of the outdoor weather conditions and spatial–temporal effects.

METRO GROUP’s wholesale and hypermarket stores prove significant reductions in electricity and total energy consumption over the analyzed timeframe. Due to the implemented energy consumption and carbon emission reduction targets, the influence of the energy management measures, such as the identification of stores associated with the lowest energy performance, was found to contribute toward a more efficient corporate environmental performance.

In the context of corporate responsibility/sustainability of wholesale, hypermarket and retail corporations, the energy efficiency and reduction of carbon emissions from corporates’ real estate assets is of emerging interest. Besides the insights about the energy efficiency of corporate real estate assets, the role of the energy management, contributing to a more efficient corporate environmental performance, is not yet investigated for a large European wholesale and hypermarket portfolio.

With pressing issues of climate change, greening buildings have emerged as a viable solution for meeting the increasing demand for buildings with minimal environmental impacts. Hence, the purpose of this paper is to establish the possibility of achieving this goal by investigating the drivers, challenges, and critical success factors (CSFs) involved in greening existing buildings. Since most of the relevant literature focuses on only acknowledging CSFs for new building projects in general, this study seeks to distinguish CSFs that are particularly related to the greening of existing buildings.

Based on a review of past literature, 28 selected factors were identified and were categorised into five main groups, namely pre-project-related factors, project management-related factors, client-related factors, project team-related factors, and external factors. Because older buildings have more constraints than new buildings, a comparison of the CSFs for greening new and existing buildings was also made. Surveys and interviews were conducted to validate the CSFs identified.

The top CSFs in each building category (new vs existing) were then further examined and analysed. These are “top management support”, “effective planning and control”, “building owner's involvement”, “cost management”, “responsiveness of building owners”, “clear scope and priorities of stakeholders”, and “legislation”. Furthermore, there was a strong consensus on the rankings of most factors between new and existing buildings.

By understanding the factors that are crucial for managing and delivering successful green projects in the Singaporean context, these CSFs can be used to direct an organisation's efforts in identifying critical issues and tackling them to achieve high performance.

An ambitious goal of greening 80 per cent of Singapore's building stocks has been set by the government in the Second Green Building Master Plan. To help achieve this goal, this study contributes to the knowledge of project management issues that would determine the success of managing new green building projects and retrofitting existing ones.

The purpose of this paper is to explore perceptions of the advantages and disadvantages of green roofs for commercial real estate building owners/occupiers in a UK city and consider how these might affect the chances of their adoption.

Two sets of semi-structured interviews were conducted with purposively selected respondents, 10 with and 25 without green roofs, to compare and contrast differing perspectives. A grounded theory approach was taken to data analysis, allowing themes to emerge directly from the data.

Low awareness and understanding were observed amongst those without green roofs, which positively affected perceived costs whilst negatively affecting perceived benefits. Green roof owners gave weight to wider societal and ecosystem services benefits, whilst those without focussed much more upon building-level benefits and costs.

Because of the restricted sample size, the findings in themselves are not generalizable; rather, themes are drawn from the research for reflection.

Findings point to steps that might be required of regional and national government to increase green roof uptake. This could involve initiating conversations to raise awareness, shift discourse and perceived norms and best practice; offering incentives, education and training; and presenting high-profile exemplar projects of green roofing to begin to mainstream the technology and get it onto the radar of building owners.

Bringing together social research around cohorts with and without green roofs, the paper throws into sharp relief discussions around costs and benefits and points towards potentially more productive directions for action to encourage consideration and take-up of green roofs by building owners.

The purpose of this paper is to simulate the behaviour of the symmetrical turn‐up vortex amplifier (STuVA) to obtain insight into its maximum through‐flow operation within the eight‐port STuVA, and understand the relation between its design parameters and flow characteristics. Furthermore, it is to test the performance of different turbulent models and near‐wall models using the same grid, the same numerical methods and the same computational fluid dynamics code under multiple impingement conditions.

Three turbulence models, the standard k‐ε, the renormalization group (RNG) k‐ε model and the Reynolds stress model (RSM), and three near‐wall models have been used to simulate the confined incompressible turbulent flow in an eight‐port STuVA using unstructured meshes. The STuVA is a special symmetrical design of turn‐up vortex amplifier, and the simulation focused on its extreme operation in the maximum flow state with no swirling. The predictions were compared with basic pressure‐drop flow rate measurements made using air at ambient conditions. The effect of different combinations of turbulence and near‐wall models was evaluated.

The RSM gave predictions slightly closer to the experimental data than the other models, although the RNG k‐ε model predicted nearly as accurately as the RSM. They both improved errors by about 3 per cent compared to the standard k‐ε model but took a long time for convergence. The modelling of complex flows depends not only on the turbulence model but also on the near‐wall treatments and computational economy. In this study a good combination was the RSM, the two layer wall model and the higher order discretization scheme, which improved accuracy by more than 10 per cent compared to the standard k‐ε model, the standard wall function and first order upwind.

The results of this paper are valid for the global pressure drop flow rate. It should be desirable to compare some local information with the experiment.

This paper provides insight into the maximum through‐flow operation within the eight‐port STuVA to understand the relation between its design parameters and flow characteristics and study the performance of turbulence and near wall models.

The purpose of this paper is to conduct a numerical analysis of transient turbulent natural convection combined with surface thermal radiation in a square cavity with a local heater.

The domain of interest includes the air-filled cavity with cold vertical walls, adiabatic horizontal walls and isothermal heater located on the bottom cavity wall. It is assumed in the analysis that the thermophysical properties of the fluid are independent of temperature and the flow is turbulent. Surface thermal radiation is considered for more accurate analysis of the complex heat transfer inside the cavity. The governing equations have been discretized using the finite difference method with the non-uniform grid on the basis of the special algebraic transformation. Turbulence was modeled using the k–ε model. Simulations have been carried out for different values of the Rayleigh number, surface emissivity and location of the heater.

It has been found that the presence of surface radiation leads to both an increase in the average total Nusselt number and intensive cooling of such type of system. A significant intensification of convective flow was also observed owing to an increase in the Rayleigh number. It should be noted that a displacement of the heater from central part of the bottom wall leads to significant modification of the thermal plume and flow pattern inside the cavity.

An efficient numerical technique has been developed to solve this problem. The originality of this work is to analyze unsteady turbulent natural convection combined with surface thermal radiation in a square air-filled cavity in the presence of a local isothermal heater. The results would benefit scientists and engineers to become familiar with the analysis of turbulent convective–radiative heat transfer in enclosures with local heaters, and the way to predict the heat transfer rate in advanced technical systems, in industrial sectors including transportation, power generation, chemical sectors and electronics.