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CFD simulations were conducted to assess turbulent forced convection heat transfer and pressure drop through a ventilation channel using a stack of panels with different ridge configurations containing Phase Change Material (PCM). First, an experimental rig using an existing commercial panel provided by a PCM manufacturer validates the model simulated in Ansys FLUENT. After that, 3D simulations with different designs were tested until the optimum configuration in terms of heat transfer and pressure drop was achieved.

The aim was to study how the cooling jet from the ceiling, with individual control over the airflow, is perceived and how it affects the thermal comfort in warm office environment. 32 undergraduate university students participated in the experiment. Two thermal conditions were tested: (1) no cooling jet and (2) adjustable cooling jet from the ceiling. Subjects were able to use a controller with seven different settings to adjust the airflow coming from the nozzles so that the target velocity varied from 0.3 m/s to 1.5 m/s. The cooling jet was directed into the upper body.

Shopping centres currently design has included a small portion of automated windows sized for smoke ventilation. Their presence is mandatory for fire regulation and they are usually operated just in case of fire. Nevertheless, these buildings can potentially take advantage of those openable windows to exploit the potential of natural ventilation to guarantee the minimum air change rate required by IAQ standards and for ventilative cooling purpose reducing cooling and electrical consumption.

Night ventilation is used extensively as a low energy strategy to cool buildings in climates where night temperatures are suitable. It can be used for spaces utilising natural or mechanical ventilation systems as well as active refrigerant cooling. Most published work focuses on domestic and relatively simple in operation commercial buildings such as offices. This paper presents a study of the cooling benefits of night ventilation for frozen food supermarkets with high cooling demand.

With the goal of increasing building flexibility and reducing energy use, yet ensuring IAQ, the feasibility of natural ventilation in a building in Oslo is studied. However, the use of direct outdoor air poses some challenges in the Norwegian cold climate, particularly the risk of thermal discomfort due to draught and low local temperatures. The goal of this paper is to study the most suitable solution to avoid draught in cold climates while maintaining the required airflow rates.

New buildings have to satisfy stricter standards regarding energy efficiency and consumption. This results in higher insulation levels and lower air leakages that reduce heating demands. However, together with the heating demands reductions, higher temperatures in summer and particularly shoulder season are more frequent even at moderate to cold climates. In order to ensure acceptable indoor environment quality, removal of excess heat becomes unavoidable. Using mechanical cooling in residential buildings is considered incompatible with achieving zero energy buildings (ZEB).

Nearly all retail locations use mechanical cooling systems to ensure indoor comfort temperatures and mechanical ventilation to ensure adequate air exchange, primarily for hygienic reasons. Because of the big volumes involved and the lack of knowledge in natural ventilation design, shopping centres designers have been relying on basic HVAC equipment, without considering the potential of ventilative cooling to reduce cooling needs and to maintain an acceptable indoor environmental quality.

Increasing use of air-conditioning in India is applying upward pressure on energy demand and may have implications on dependability. Electrical energy can be saved if favourable outdoor conditions are effectively utilized for cooling buildings with the minimum use of energy. This could be specifically applicable to residences where night-time use is more predominant for cooling by air conditioning systems but also aligns favourably with suitable outdoor conditions to be used as ventilative cooling.

It is estimated that HVAC systems represent the highest energy consumption (approximately half of the total energy consumed) and one of the highest cost, especially in non-residential buildings. Therefore, that energy consumption in related to the cost of the building, the energy consumption and the thermal comfort.
Although the comfort of the users should be a factor to be aware of, it may not be the only one. It is advisable to have a balance between this variable and energy consumption, because of its impact on the environment and climate change.

The use of open-source CFD has been growing in both industry and academia. Open-source CFD saves users a considerable license cost and provides users with full transparency of implementation and maximum freedom of customization. However, it is often necessary to assess the performance of an open-source code before applying it to the practical use. This study applies one of the most popular open-source CFD codes – OpenFOAM to the indoor airflow and heat transfer prediction. The performance of OpenFOAM is evaluated and validated against a well-documented benchmark test.