Khaled A. Al-Sallal

Khaled A. Al-Sallal


Research Focus & Metrics

Academic Career Length

26Years (2001-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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19 March 2019 in Energies
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Journal Article
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AAAmira AbouElhamd
Amira AbouElhamd
KAKhaled A. Al-Sallal
Khaled A. Al-Sallal
AHAhmed Hassan
Ahmed Hassan
Skylights and windows are building openings that enhance human comfort and well-being in various ways. Recently, a massive drive is witnessed to replace traditional openings with building integrated photovoltaic (BIPV) systems to generate power in a bid to reduce buildings’ energy. The problem with most of the BIPV glazing lies in the obstruction of occupants’ vision of the outdoor view. In order to resolve this problem, new technology has emerged that utilizes quantum dots semiconductors (QDs) in glazing systems. QDs can absorb and re-emit the incoming radiation in the desired direction with the tunable spectrum, which renders them favorable for building integration. By redirecting the radiation towards edges of the glazing, they can be categorized as luminescent solar concentrators (QD-LSCs) that can help to generate electricity while maintaining transparency in the glazing. The aim of this paper is to review the different properties of core/shell quantum dots and their potential applications in buildings. Literature from various disciplines was reviewed to establish correlations between the optical and electrical properties of different types, sizes, thicknesses, and concentration ratios of QDs when used in transparent glazing. The current article will help building designers and system integrators assess the merits of integrating QDs on windows/skylights with regards to energy production and potential impact on admitted daylighting and visual comfort.

10 October 2016 in Sustainability
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Journal Article
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AHAhmed Hassan
Ahmed Hassan
KAKhaled A. Al-Sallal
Khaled A. Al-Sallal
HAHamza Alnoman
Hamza Alnoman
YRYasir Rashid
Yasir Rashid
SAShaimaa Abdelbaqi
Shaimaa Abdelbaqi
In the current study, a phase change material (PCM) contained in an insulated concrete block is tested in extremely hot weather in the United Arab Emirates (UAE) to evaluate its cooling performance. An insulated chamber is constructed behind the block containing PCM to mimic a scaled down indoor space. The effect of placement of the PCM layer on heat gain indoors is studied at two locations: adjacent to the outer as well as the inner concrete layer. The inclusion of PCM reduced heat gain through concrete blocks compared to blocks without PCM, yielding a drop in cooling load indoors. The placement of PCM and insulation layers adjacent to indoors exhibited better cooling performance compared to that adjacent to the outdoors. In the best case, a temperature drop of 8.5% and a time lag of 2.6 h are achieved in peak indoor temperature, rendering a reduction of 44% in the heat gain. In the tested hot climate, the higher ambient temperature and the lower wind speed hampered heat dissipation and PCM re-solidification by natural ventilation. The findings recommend employing a mechanical ventilation in hot climates to enhance regeneration of the PCM to solid state for its optimal performance.

3 August 2010 in International Journal of Low-Carbon Technologies
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Journal Article
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KAKhaled A. Al-Sallal
Khaled A. Al-Sallal
The study focuses on analysis of visual performance and quality issues in classrooms located in the United Arab Emirates (UAE). The methodology depended on data collection and analysis of design information obtained from architectural drawings of standard schools, design compliance documents set by the relevant governmental bodies, and site visits and photography. It analyzed several important design issues that have significant impact on visual quality, including space size and depth to height ratio, windows orientation, lighting direction and desk position. It used simulation to investigate potential visual problems during critical times and view angles. Several problems concerning contrasting luminance levels in the field of view were identified and described. Mitigation of the problems using recommended daylighting systems was discussed based on the UAE climate.

31 July 2011 in Sustainable Cities and Society
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Journal Article
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KAKhaled A. Al-Sallal
Khaled A. Al-Sallal
MDMaitha M. Bin Dalmouk
Maitha M. Bin Dalmouk

1 December 2001 in Architectural Science Review
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Journal Article
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KAKhaled A. Al-Sallal
Khaled A. Al-Sallal
This study investigates the critical balance between form and space used as the main approach to mitigate the effect of the climate and provide the functional requirements of culture such as space activity, privacy, and view. Sana'a architecture is used as a case study; it is considered as a rich resource for exploring climatic design solutions due to its history-long experiences. The approach depends on a number of methods for analysis of common architectural practices such as passive solar thermal performance analysis, solar access and shading analysis using 3D computer modeling and observation and literature survey of cultural aspects. The analysis is based on the form-space relationship in the vernacular tower house of Sana'a. The paper presents a summary of the study's outcomes as rules of thumb in formats that can be used for application in design.

1 January 2013 in Journal of Building Performance Simulation
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Journal Article
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KAKhaled A. Al-Sallal
Khaled A. Al-Sallal
LALaila Al-Rais
Laila Al-Rais
The ability to simulate the effect of trees on natural light performance in buildings is contingent upon accurate simulation of light passing through the canopy. Accurate simulations require some assumption of leaf angle distribution (LAD) to compute canopy gap fractions. The ellipsoidal LAD can very closely approximate real plant canopies. The method requires calculation of leaf area density from observed distribution of gap fraction as a function of zenith angle. Two sets of Neem trees were studied (small and large). Hemispherical image acquisition and analysis for both groups was carried out to measure gap fractions. The results helped to develop a 3D tree model that was used to simulate the effect of tree interception of daylight. The illuminance levels were simulated under the tree model and the output results were validated against actual measurements using MBE and RMSE techniques (small trees: MBE = 0.33, RMSE = 0.20; large trees: MBE = 9.68, RMSE = 2.02).