Payam Nejat

Bauhaus-Universität Weimar · Building Physics

In the pursuit of sustainable and energy-efficient buildings, there is a growing interest in natural ventilation solutions. In this regard, windcatchers have surfaced as viable devices for achieving passive cooling, enhancing indoor air quality, and reducing reliance on mechanical ventilation systems in modern architecture. While windcatchers have...

Windcatcher natural ventilation is a low-energy approach that can provide effective ventilation during favourable weather conditions. When combined with different cooling, heating, and dehumidification technologies, windcatchers can provide enhanced indoor environment quality. This work provides a critical review of wind-catchers' performance. It c...

In recent years, there has been increased interest in natural ventilation solutions as a means to achieve sustainable and energy-efficient building design. Windcatchers, ancient Middle Eastern architectural elements, have surfaced as viable passive cooling devices in modern architecture, thereby enhancing interior air quality and reducing the relia...

Inadequate indoor ventilation can lead to microbial contamination in enclosed spaces, necessitating improvements in indoor air quality (IAQ). To address this, ‘add-on systems' can be employed—additional, independently installable devices within indoor environments, often separate from the HVAC system. This study comprehensively assesses various add...

The building sector is one of the main players in the global energy market. Passive strategies such as natural ventilation are promising techniques toward sustainable targets in this sector. Windcatchers as a natural ventilation system can provide fresh air and improve thermal comfort. However, the performance evaluation of windcatchers is still a...

Windcatchers are a promising natural ventilation alternative to conventional ventilation systems. In recent years, many studies attempted to address the different gaps in the field but the impact of terrain type on the performance of windcatchers is still an unexplored topic. Therefore, this paper investigates how the windcatcher's ventilation perf...

Windcatchers are known as environment-friendly architectural elements that provide buildings with effective wind-induced natural ventilation. Air shortcircuit is an unintended air path that should be prevented due to the negative impact on the ventilation performance of windcatchers. This study aims to numerically evaluate the effect of five differ...

The Savonius wind turbine is one of the most well-known vertical axis wind turbines with insensitivity to wind direction, flow turbulence, and high torque generation. These turbines can extract up to 20% of the energy from the wind. This study numerically analyzes the performance of a modified Savonius wind turbine equipped with secondary blades an...

The upper wing wall can be integrated into the windcatcher to prevent direct solar and rain penetration. The impact of this combination was not considered in previous studies. Moreover, analyzing adaptive thermal comfort is another gap that was not addressed by preceding windcatcher studies, particularly for the tropical climate. Therefore, the cur...

The significant energy use and increasing requirement for good indoor environment quality in the built environment have led to a renewed interest in natural ventilation strategies such as windcatchers. Windcatcher is a roof-mounted device that supplies fresh airflow into a room and expels polluted air under the action of wind pressure and buoyancy...

Windcatchers are considered as promising passive ventilation and cooling strategy, but the ventilation performance of this system is still of concern in areas with low speed and unpredictable winds. The air short circuiting in windcatchers can reduce its ventilation performance and ability to introduce clean air and remove stale air. The current wo...

Two third of buildings’ energy consumption is associated to HVAC systems. Windcatcher is a green traditional method of natural ventilation which has been applied for centuries in Middle East. Nevertheless, tropical climate, this green feature is not a common architectural element. In Malaysia as a developing country, buildings account for 23% of to...

Generally, two-third of a building’s energy is consumed by heating, ventilation and air-conditioning systems. One green alternative for conventional air conditioner systems is the implementation of passive cooling. Wing walls and windcatchers are two prominent passive cooling techniques which use wind as a renewable resource for cooling. However, i...

Global demand for energy continues to increase rapidly, due to economic and population growth, especially for increasing market economies. These lead to challenges and worries about energy security that can increase as more users need more energy resources. Also, higher consumption of fossil fuels leads to more greenhouse gas emissions, which contr...

The data presented in this article were the basis for the study reported in the research articles entitled “Evaluation of a two-sided windcatcher integrated with wing wall (as a new design) and comparison with a conventional windcatcher” (P. Nejat, J.K. Calautit, M.Z.A. Majid, B.R. Hughes, I. Zeynali, F. Jomehzadeh, 2016) [1] which presents the eff...

This article presents the datasets which were the results of the study explained in the research paper ‘Anti-short-circuit device: a new solution for short-circuiting in windcatcher and improvement of natural ventilation performance’ [1] which introduces a new technique to reduce or prevent short-circuiting in a two-sided windcatcher and also lower...

The most significant threat that mankind faces in the 21th century is global warming. Buildings, which account for 40% of global energy consumption and greenhouse gas emissions, play a pivotal role in global warming. Estimates show that their destructive impact will grow by 1.8% per year through 2050, which indicates that future consumption and emi...

In buildings, 60% of the energy consumption is associated to Heating, Ventilation and Air-conditioning (HVAC) systems. One solution to reduce this share is the application of natural ventilation systems. Windcatcher and wing wall are two well-known techniques for natural ventilation which have been used in different regions. Nevertheless, in areas...

Abstract Windcatcher is an effective technique for naturally ventilating a space and improving indoor air quality. A common problem for modern and traditional windcatchers is air short-circuiting. Air-short-circuiting in windcatchers occurs when the air entering through the supply channel immediately exits through the exhaust channel without circul...

Whole body vibration produces some serious problems for human health in the long term. Low-frequency vibration, generated during vehicle operation, and transmitted to the vehicle operator, plays a major role in the development of low-back pain. Back pain is one of epidemic injuries in heavy duty vehicle drivers. Generally seat suspensions are desig...

Since the beginning of the last century, energy affairs have always been taken into global consideration due to their effects on economies, policies, security and the environment. Fossil fuels have been the first recourse for global energy supply needs (80% of total energy consumption); nonetheless, owing to the production of greenhouse gases, they...