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Article
Publication date: 3 April 2019

Michael Maks Davis, Andrea Lorena Vallejo Espinosa and Francisco Rene Ramirez

Vertical gardens offer multiple benefits in urban environments, including passive cooling services. Previous research explored the use of “active vertical gardens” as potential…

Abstract

Purpose

Vertical gardens offer multiple benefits in urban environments, including passive cooling services. Previous research explored the use of “active vertical gardens” as potential evaporative air-cooling units by developing a mathematical model based on the FAO-56 Penman Monteith equation. Further research showed that active vertical gardens function best by creating an airflow in the cavity behind the garden such that air is cooled by flowing over the water-saturated garden substrate. The purpose of this paper is to improve the quantification of active vertical garden performance.

Design/methodology/approach

A building-incorporated vertical garden was built in Quito, Ecuador, with an air inlet at the top of the garden, an air cavity behind the garden and where air was expelled from the base. Measurements were made of air temperature, humidity and velocity at the air inlet and outlet.

Findings

The active vertical garden cooled the air by an average of 8.1 °C with an average cooling capacity of 682.8 W. Including the effects of pre-cooling at the garden inlet, the garden cooled the air by an average of 14.3 °C with an average cooling capacity of 1,203.2 W.

Originality/value

The results are promising and support the potential for active vertical gardens to be incorporated into building services and climate control.

Details

Smart and Sustainable Built Environment, vol. 8 no. 3
Type: Research Article
ISSN: 2046-6099

Keywords

Article
Publication date: 3 August 2015

Motahareh Mokhtari Yazdi, Mohammad Sheikhzadeh and Seyed Ehsan Chavoshi

The purpose of this paper is to identify and evaluate the potential cooling contribution provided by a phase change material cooling vest as part of the total heat exchange…

Abstract

Purpose

The purpose of this paper is to identify and evaluate the potential cooling contribution provided by a phase change material cooling vest as part of the total heat exchange mechanism of the body and take in to account the negative side effects of wearing the cooling garments.

Design/methodology/approach

In this study, the three-part system of body-garment-environment has been simulated through the finite element method and the problem of heat exchange between these three parts has been solved with the help of computer modeling.

Findings

The results of this modeling showed that a large percentage of the cooling efficiency of cooling vest was neutralized by the negative effects of the vest that are weight, lack of breathability, and the effects on the thermal conductivity of the skin. Therefore, the net efficiency of the cooling vests resulted in a lower decrease in skin temperature compared to the state that the negative side effects were not included in the model.

Originality/value

Cooling power obtained with the help of cooling garments have been studied in previous studies using either human tests or manikins. But, what has been addressed less in previous studies relates to the negative effects of such equipment on the comfort of body, along with their cooling effect. So it is the first time witch the effect of side effects of such equipments are studied. Also modeling the real performance of cooling garments have not been done yet.

Details

International Journal of Clothing Science and Technology, vol. 27 no. 4
Type: Research Article
ISSN: 0955-6222

Keywords

Article
Publication date: 1 April 2021

Emmanuel Imuetinyan Aghimien, Danny Hin Wa Li and Ernest Kin-Wai Tsang

This paper reviews extant studies on bioclimatic architecture with a view of revealing the focus areas of past studies and mapping out future research directions useful in…

1199

Abstract

Purpose

This paper reviews extant studies on bioclimatic architecture with a view of revealing the focus areas of past studies and mapping out future research directions useful in achieving building energy efficiency.

Design/methodology/approach

A mixed-method systematic review that integrates quantitative and qualitative analysis was adopted. The bibliographic data were extracted from the Scopus database, and a scientometric analysis was conducted to analyse the data quantitatively. Qualitative content analysis is then presented, which provided a basis for mapping out trends and gaps in current knowledge.

Findings

It is observed that there has been a rise in the number of studies on bioclimatic architecture over the last two decades. Past studies have focused on sustainability, building performance simulation, building climatology and energy use, solar energy applications and passive cooling. Artificial intelligence, algorithm coupling and acoustic comfort were some of the emerging areas discovered in this study.

Research limitations/implications

The study reveals research gaps that researchers can investigate.

Practical implications

The information provided can help the building industry stakeholders in decision-making. It serves as a guideline for maximising the potential benefits of adopting bioclimatic designs in the building industry. Furthermore, it provides references that aid policy formulation for government agencies and corporate organisations.

Originality/value

The study fills the literature gap caused by the need for a holistic literature review that relates bioclimatic architecture and its energy efficiency implications. It is also the first study on bioclimatic architecture that adopts a mix of scientometric and qualitative analysis for analysing past studies on bioclimatic architecture.

Details

Engineering, Construction and Architectural Management, vol. 29 no. 2
Type: Research Article
ISSN: 0969-9988

Keywords

Article
Publication date: 6 August 2019

Meysam Yari, Rasool Kalbasi and Pouyan Talebizadehsardari

This study aims to simulate the flow and heat transfer through an air handling unit to reduce its energy consumption by a novel creative idea of using an air-to-air heat exchanger.

Abstract

Purpose

This study aims to simulate the flow and heat transfer through an air handling unit to reduce its energy consumption by a novel creative idea of using an air-to-air heat exchanger.

Design/methodology/approach

To do this, both first and second laws of thermodynamics energy and exergy balance equations were solved numerically by an appropriate developed computer code.

Findings

Using the air-to-air heat exchanger in dry conditions decreases the cooling coil load by 0.9 per cent, whereas the reduction for humid conditions is 27 per cent. Similarly, using air-to-air heat exchanger leads to an increase in the first law of efficiency in dry and humid conditions by 0.9 per cent and 36.8 per cent, respectively.

Originality/value

The second law of efficiency increases by 1.55 per cent and 2.77 per cent in dry and humid conditions, respectively. In other words, the effect of using an air-to-air heat exchanger in humid conditions is more than that in dry conditions.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 29 no. 10
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 11 June 2018

Louma Ahmad Chaddad, Ali Chehab, Imad Elhajj and Ayman Kayssi

The purpose of this paper is to present an approach to reduce energy consumption in data centers. Subsequently, it reduces electricity bills and carbon dioxide footprints…

Abstract

Purpose

The purpose of this paper is to present an approach to reduce energy consumption in data centers. Subsequently, it reduces electricity bills and carbon dioxide footprints resulting from their use.

Design/methodology/approach

The authors present a mathematical model of the energy dissipation optimization problem. The authors formulate analytically the server selection problem and the supply air temperature as a non-linear programming, and propose an algorithm to solve it dynamically.

Findings

A simulation study on SimWare, using real workload traces, shows considerable savings for different data center sizes and utilization rates as compared to three other classic algorithms. The results prove that the proposed algorithm is efficient in handling the energy-performance trade-off, and that the proposed algorithm provides significant energy savings and maintains a relatively homogenous and stable thermal state at the different rack units in the data center.

Originality/value

The proposed algorithm ensures energy provisioning, performance optimization over existing state-of-the-art heuristics, and on-demand workload allocation.

Details

Management of Environmental Quality: An International Journal, vol. 29 no. 4
Type: Research Article
ISSN: 1477-7835

Keywords

Article
Publication date: 26 June 2023

Sarah Nazari, Payam Keshavarz Mirza Mohammadi, Amirhosein Ghaffarianhoseini, Ali Ghaffarianhoseini, Dat Tien Doan and Abdulbasit Almhafdy

This paper aims to investigate the optimization of window and shading designs to reduce the building energy consumption of a standard office room while improving occupants'…

Abstract

Purpose

This paper aims to investigate the optimization of window and shading designs to reduce the building energy consumption of a standard office room while improving occupants' comfort in Tehran and Auckland.

Design/methodology/approach

The NSGA-II algorithm, as a multi-objective optimization method, is applied in this study. First, a comparison of the effects of each variable on all objectives in both cities is conducted. Afterwards, the optimal solutions and the most undesirable scenarios for each city are presented for architects and decision-makers to select or avoid.

Findings

The results indicate that, in both cities, the number of slats and their distance from the wall are the most influential variables for shading configurations. Additionally, occupants' thermal comfort in Auckland is much better than in Tehran, while the latter city can receive more daylight. Furthermore, the annual energy use in Tehran can be significantly reduced by using a proper shading device and window-to-wall ratio (WWR), while building energy consumption, especially heating, is negligible in Auckland.

Originality/value

To the best of the authors' knowledge, this is the first study that compares the differences in window and shading design between two cities, Tehran and Auckland, with similar latitudes but located in different hemispheres. The outcomes of this study can benefit two groups: firstly, architects and decision-makers can choose an appropriate WWR and shading to enhance building energy efficiency and occupants' comfort. Secondly, researchers who want to study window and shading systems can implement this approach for different climates.

Details

Smart and Sustainable Built Environment, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2046-6099

Keywords

Article
Publication date: 1 February 1971

B.C. VICKERY

Retrieval languages may have varied structural characteristics, and these are summarized. The languages serve varied purposes in information systems, and a number of these are…

Abstract

Retrieval languages may have varied structural characteristics, and these are summarized. The languages serve varied purposes in information systems, and a number of these are identified. The relations between structure and function are discussed and suggestions made as to the most suitable structures needed for various purposes.

Details

Journal of Documentation, vol. 27 no. 2
Type: Research Article
ISSN: 0022-0418

Article
Publication date: 28 February 2023

Emmanuel Otchere-Darko, Laura Atuah, Richard Opoku and Christian Koranteng

Green roofs are strategies for the ecological intensification of cities and a measure of meeting some of the sustainable development goals (SDGs). They have widely been adopted as…

Abstract

Purpose

Green roofs are strategies for the ecological intensification of cities and a measure of meeting some of the sustainable development goals (SDGs). They have widely been adopted as an adaptation strategy against an urban heat island (UHI). However, they are conventionally soil-based making it difficult and expensive to adopt as a strategy for greening existing buildings (GEB). This paper, therefore, develops a novel green roof system using climbers for thermal-radiative performance. The paper explores the vitality of climbing species as a nature-based strategy for GEB, and for the ecological improvement of the predominantly used cool roofs in sub-Saharan Africa (SSA).

Design/methodology/approach

Simulation for the same building Kejetia Central Market (KCM) Redevelopment; the existing aluminium roof (AL), soil-based extensive green roof (GR1) and the proposed green roof using climbing plants (GR2) were performed using ENVI-met. The AL and GR1 were developed as reference models to evaluate and compare thermal-radiative performance of the conceptual model (GR2). The long wave radiation emission (Qlw), mean radiant temperature (MRT) and outdoor air temperature (Ta) of all three roofing systems were simulated under clear sky conditions to assess the performance and plant vitality considering water access, leaf temperature (Tf) and latent heat flux (LE0) of GR1 and GR2.

Findings

There was no short wave radiation (Qsw) absorption at the GR2 substrate since the climbers have no underlying soil mass, recording daily mean average Qlw emission of 435.17 Wm−2. The soil of GR1, however, absorbed Qsw of 390.11 Wm−2 and a Qlw emission of 16.20 wm−2 higher than the GR2. The AL recorded the lowest Qlw value of 75.43 Wm−2. Also, the stomatal resistance (rs) was higher in GR1 while GR2 recorded a higher average mean transpiration flux of 0.03 g/sm3. This indicates a higher chance of survival of the climbers. The Ta of GR2 recording 0.45°C lower than the GR1 could be a good UHI adaptation strategy.

Research limitations/implications

No previous research on climbers for green roof systems was found for comparison, so the KCM project provided a unique confluence of dynamic events including the opportunity for block-scale impact assessment of the proposed GEB strategy. Notwithstanding, the single case study allowed a focussed exploration of the novel theory of redefining green roof systems with climbers. Moreover, the simulation was computationally expensive, and engaging multiple case studies were found to be overly exhaustive to arrive at the same meaningful conclusion. As a novelty, therefore, this research provides an alternative theory to the soil-based green roof phenomenon.

Practical implications

The thermal-radiative performance of green roofs could be improved with the use of climbers. The reduction of the intensity of UHI would lead to improved thermal comfort and building energy savings. Also, very little dependence on the volume of soil would require little structural load consideration thereby leading not only to cheaper green roof construction but their higher demand, adoption and implementation in SSA and other low-income economies of the global south.

Social implications

The reduction of the consumption of topsoil and water for irrigation could avoid the negative environmental impacts of land degradation and pollution which have a deleterious impact on human health. This fulfils SDG 12 which seeks to ensure responsible consumption of products. This requires the need to advance the research for improvement and training of local built environment practitioners with new skills for installation to ensure social inclusiveness in the combat against the intractable forces of negative climate impacts.

Originality/value

Climbers are mostly known for green walls, but their innovative use for green roof systems has not been attempted and adopted; it could present a cost-effective strategy for the GEB. The proposed green roof system with climbers apart from becoming a successful strategy for UHI adaptation was also able to record an estimated 568% savings on topsoil consumption with an impact on the reduction of pollution from excavation. The research provides an initial insight into design options, potentials and limitations on the use of climbers for green roofs to guide future research and experimental verification.

Details

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

Keywords

Article
Publication date: 28 September 2020

Hery Sonawan, Evi Sofia and Arief Ramadhan

The paper aims to apply Buckingham Pi dimensional analysis method for assessing direct evaporative cooler performance with a cooling pad made of banana midrib and ramie fiber. The…

Abstract

Purpose

The paper aims to apply Buckingham Pi dimensional analysis method for assessing direct evaporative cooler performance with a cooling pad made of banana midrib and ramie fiber. The saturation efficiency acted as the indicator performance of the evaporative cooler.

Design/methodology/approach

The paper describes an experimental study of the direct evaporative cooler with a cooling pad made of banana midrib and rami fiber. There were six parameters in the experiment: absorbed water as a dependent variable was affected by independent parameters such as air velocity and temperature, cooling pad cross-section area and thickness. Based on these variables, we arranged three dimensionless numbers and their correlation.

Findings

The paper provides three calculated dimensionless numbers plotted on a curve with a specific correlation. The curve trends for 30 mm and 50 mm pad thickness were almost similar. The range of Reynolds number for 10 mm pad was narrower than other pad thicknesses. The thicker the cooling pad, the more extensive was the calculated Reynolds number range. A new curve exhibited the relationship between the evaporation rate with the μA/t number. The broader cooling pad cross-section, the thinner pad thickness, and the lower pad temperature were factors that increased the evaporation rate, even though the increase was less significant.

Originality/value

A new material in cooling pad from banana midrib fiber was tested and compared to ramie fiber and conventional cooling pad.

Details

Smart and Sustainable Built Environment, vol. 11 no. 3
Type: Research Article
ISSN: 2046-6099

Keywords

Article
Publication date: 1 September 1951

H.R. Haerle

THE development of aircraft penumatic equipment has progressed so satisfactorily in recent years that actuation of vital services by means of compressed air is becoming…

Abstract

THE development of aircraft penumatic equipment has progressed so satisfactorily in recent years that actuation of vital services by means of compressed air is becoming increasingly popular. In this brief review of developments to date an attempt will be made to show how the air which has been made available as a result of compressor improvements is utilized and by way of introduction it may be of interest to recall some of the bold experiments which were made in earlier years.

Details

Aircraft Engineering and Aerospace Technology, vol. 23 no. 9
Type: Research Article
ISSN: 0002-2667

1 – 10 of 333