scholarly journals An Innovative Façade Element with Controlled Solar-Thermal Collector and Storage

2020 ◽  
Vol 12 (13) ◽  
pp. 5281
Author(s):  
Thomas Wüest ◽  
Lars O. Grobe ◽  
Andreas Luible
Keyword(s):  
Solar Radiation ◽  
Thermal Storage ◽  
Thermal Mass ◽  
Building Performance ◽  
Water Tank ◽  
Closed Cavity ◽  
Solar Thermal Collector ◽  
Trombe Wall ◽  
Shading Device ◽  
Heat Transfers

A novel façade element is presented that forms a symbiosis between an enhanced box-type window, a closed cavity façade, and a Trombe wall. This hybrid, transparent-opaque façade element features an absorbing water tank, that is installed behind a controlled shading device toward the cavity of a non-ventilated Double Skin Façade in the parapet section. To evaluate the potential impact on building performance, a transient simulation model is developed in Modelica and calibrated by comparison with measurements on a prototype. The effect of the absorbing thermal storage on heat transfers under solar radiation is analyzed in comparison to (i) conditions excluding solar radiation and (ii) an empty tank. An evaluation for four European cities demonstrates that the annual heating demand can be reduced by more than 4.2% and cooling demand by at least 6.6% compared to a façade without thermal storage. The effect is explained not only by the increased thermal mass, but also by the effective modulation of solar gains by the controlled absorbing storage. The dampening of heat flow fluctuations and the control of solar gains is a promising means to reduce the installed power of HVAC (heating/ventilating/air conditioning) installations.

scholarly journals Reuse Waste Material and Carbon Dioxide Emissions to Save Energy and Approach Sustainable Lightweight Portable Shelters

2020 ◽  
Vol 24 (1) ◽  
pp. 143-161
Author(s):  
Ammar Alkhalidi ◽  
Yara Nidal Zaytoun
Keyword(s):  
Solar Radiation ◽  
Carbon Dioxide Emissions ◽  
Concrete Slab ◽  
Winter Season ◽  
Thermal Storage ◽  
Thermal Mass ◽  
Night Time ◽  
Lightweight Structures ◽  
Heating Load ◽  
Simulation Results

AbstractDespite their great significance, lightweight structures have poor thermal inertia. In order to enhance the thermal comfort inside such buildings, architects need lightweight thermal storage. In this paper a model was used to experimentally investigate Heating Load profiles in lightweight shelters. The profiles were created for the climate in Jordan, then simulated for other climate zones. The proposed design concept was used to create a replacement for a thermal mass in lightweight structures such as shelters; by combining passive solar gain with energy storage embodied within the shelter floor (thermal-floor) to absorb solar radiation. This shelter design decreased the Heating Load during the winter season by acting as heat storage that releases energy at night time after being exposed to solar radiation during the day. The passive design depends on shading elements and overhangs shades to control solar gain during different seasons to prevent overheating during the summer. An experimental investigation of this model was performed to validate the simulation results. Validated simulation results showed that the designed thermal-floor is 25 % of the total shelter’s floor area, which was crucial for obtaining favourable results. With CO2 as a thermal mass, heat load was reduced up to 68 % compared to a 20 cm concrete slab floor. The use of this thermal storage material yielded a reduction in annual heating demand by 85 kWh/m2.

scholarly journals Thermal comfort in winter incorporating solar radiation effects at high altitudes and performance of improved passive solar design—Case of Lhasa

2020 ◽  
Author(s):  
Lingjiang Huang ◽  
Jian Kang
Keyword(s):  
Solar Radiation ◽  
Thermal Comfort ◽  
Energy Saving ◽  
Solar Irradiance ◽  
Indoor Environment ◽  
Thermal Mass ◽  
High Altitudes ◽  
Energy Saving Potential ◽  
Environment Control ◽  
Passive Solar

AbstractThe solar incidence on an indoor environment and its occupants has significant impacts on indoor thermal comfort. It can bring favorable passive solar heating and can result in undesired overheating (even in winter). This problem becomes more critical for high altitudes with high intensity of solar irradiance, while received limited attention. In this study, we explored the specific overheating and rising thermal discomfort in winter in Lhasa as a typical location of a cold climate at high altitudes. First, we evaluated the thermal comfort incorporating solar radiation effect in winter by field measurements. Subsequently, we investigated local occupant adaptive responses (considering the impact of direct solar irradiance). This was followed by a simulation study of assessment of annual based thermal comfort and the effect on energy-saving potential by current solar adjustment. Finally, we discussed winter shading design for high altitudes for both solar shading and passive solar use at high altitudes, and evaluated thermal mass shading with solar louvers in terms of indoor environment control. The results reveal that considerable indoor overheating occurs during the whole winter season instead of summer in Lhasa, with over two-thirds of daytime beyond the comfort range. Further, various adaptive behaviors are adopted by occupants in response to overheating due to the solar radiation. Moreover, it is found that the energy-saving potential might be overestimated by 1.9 times with current window to wall ratio requirements in local design standards and building codes due to the thermal adaption by drawing curtains. The developed thermal mass shading is efficient in achieving an improved indoor thermal environment by reducing overheating time to an average of 62.2% during the winter and a corresponding increase of comfort time.

scholarly journals Charging-discharging characteristics of macro-encapsulated phase change materials in an active thermal energy storage system for a solar drying kiln

2017 ◽  
Vol 21 (6 Part A) ◽  
pp. 2525-2532 ◽  
Author(s):  
Shailendra Kumar ◽  
Kishan Kumar
Keyword(s):  
Phase Change ◽  
Thermal Energy ◽  
Phase Change Materials ◽  
Storage System ◽  
Thermal Storage ◽  
Water Tank ◽  
Solar Drying ◽  
Solidification Temperature ◽  
Water Storage Tank ◽  
Melting And Solidification

The present study explores suitability of two phase change materials (PCM) for development of an active thermal storage system for a solar drying kiln by studying their melting and solidification behaviors. A double glass glazing prototype solar kiln was used in the study. The storage system consisted of a water storage tank with PCM placed inside the water in high density polyethylene containers. The water in the tank was heated with help of solar energy using an evacuated tube collector array. The melting and solidification temperature curves of PCM were obtained by charging and discharging the water tank. The study illustrated the utility of the PCM in using the stored thermal energy during their discharge to enhance the temperature inside the kiln. The rate of temperature reduction was found to be higher for paraffin wax as compared to a fatty acid based PCM. The water temperature during the discharge of the PCM showed dependence on the discharge characteristics of each PCM suggesting their suitability in designing active thermal storage systems.

scholarly journals Evaluating the Effect of External Horizontal Fixed Shading Devices’ Geometry on Internal Air Temperature, Daylighting and Energy Demand in Hot Dry Climate. Case Study of Ghardaïa, Algeria

Buildings ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 348
Author(s):  
Sahar Magri Elouadjeri ◽  
Aicha Boussoualim ◽  
Hassan Ait Haddou
Keyword(s):  
Solar Radiation ◽  
Parametric Analysis ◽  
Energy Demand ◽  
Daylighting Simulation ◽  
Simulation Results ◽  
Shading Devices ◽  
Heating Loads ◽  
Shading Device ◽  
The City

The present study investigates the effect of fixed external shading devices’ geometry on thermal comfort, daylighting and energy demand for cooling and heating in the hot and dry climate of the city of Ghardaïa (Algeria). A parametric analysis was performed by using three software: RADIANCE 2.0 and DAYSIM 3.1 for daylighting simulation and TRNSYS.17 for thermal dynamic simulation. Three shading device parameters were assessed: the spacing between slats, the tilted angle and the slats installation. The vertical shading angle “VSA” is fixed; it is equal to the optimum shading angle measured for Ghardaïa. The simulation results indicate that fixed external shading devices have a significant impact on decreasing the energy demand for cooling; however, they are unable to reduce the total energy demand since they significantly increase heating loads. It was found that fixed external shading devices remove all risks associated with glare in summer by decreasing illuminance close to the window; however, they do not improve daylighting performance in winter because of glare. We note that even if the vertical shading angle “VSA” was the same for all cases, these did not present the same thermal and luminous behavior. This is mainly due to the amount and the way that the solar radiation penetrates space.

scholarly journals Analysis of the potential use of Trombe walls in Brazil: design recommendations

2020 ◽  
Vol 5 ◽  
pp. 4
Author(s):  
Fernando Antonio de Melo Sá Cavalcanti ◽  
Rosana Maria Caram
Keyword(s):  
Solar Radiation ◽  
Computer Simulations ◽  
Thermal Performance ◽  
Natural Ventilation ◽  
Solar Heating ◽  
Heating And Cooling ◽  
Heated Air ◽  
Trombe Wall ◽  
Potential Use ◽  
Passive Strategy

In this paper, the thermal performance of a standard environment was evaluated based on the use of a Trombe wall with different configurations and types of use, as the potential for using this passive strategy is still little studied in Brazil. This device is capable of absorbing energy from solar radiation by heating the air in this greenhouse and this heated air can be directed to the interior or exterior of the building depending on the purpose. This air can be used to heat the room or cool it by means of natural ventilation. The analysis of this research was based on a series of computer simulations using the EnergyPlus software, version 7.0 in order to quantify and classify the thermal performance of a standard environment equipped with this component, under the various construction configurations. Both for heating and cooling environments. The use of Trombe walls improved the thermal comfort of users in buildings located in Brazil, depending on the climate where they are located, promoting natural ventilation and passive solar heating, allowing the potential of this device to be investigated in the most diverse Brazilian regions.

scholarly journals The Effects of Courtyards on the Thermal Performance of a Vernacular House in a Hot-Summer and Cold-Winter Climate

Energies ◽  
2019 ◽  
Vol 12 (6) ◽  
pp. 1042 ◽  
Author(s):  
Shimeng Hao ◽  
Changming Yu ◽  
Yuejia Xu ◽  
Yehao Song
Keyword(s):  
Solar Radiation ◽  
Thermal Performance ◽  
Natural Ventilation ◽  
Field Measurements ◽  
Ground Level ◽  
Active Role ◽  
Thermal Mass ◽  
Cold Winter ◽  
Winter Climate ◽  
Climate Zones

Achieving comfort in hot summer and cold winter (HSCW) climate zones can be challenging, since the climate is characterized by high temperatures in the summer and relatively colder temperatures in the winter. Courtyards, along with other semi-open spaces such as verandas and overhangs, play an important role in mitigating outdoor climate fluctuations. In this research, the effects of courtyards on the thermal performance of vernacular houses in HSCW climate zones were studied via field measurements and computational fluid dynamics (CFD) models. The selected courtyard house was a representative vernacular timber dwelling situated in the southeast of Chongqing, China. The indoor and outdoor air temperature measurements revealed that the courtyard did play an active role as a climatic buffer and significantly reduced the temperature’s peak value in the summer, while during the winter, the courtyard prevented the surrounding rooms from receiving direct solar radiation, and thus to some extent acted as a heat barrier. The contributions of thermal mass are quite limited in this area, due to insufficient solar radiation in winter and general building operations. The natural ventilation mechanism of courtyard houses in HSCW zones was further studied through CFD simulations. The selected opened courtyard was compared to an enclosed structure with similar building configurations. The airflow patterns driven by wind and buoyancy effects were first simulated separately, and then together, to illustrate the ventilation mechanisms. The simulation results show that the courtyard’s natural ventilation behavior benefited from the proper openings on ground level.

scholarly journals Assessment of Indoor Environmental Quality for Retrofitting Classrooms with An Egg-Crate Shading Device in A Hot Climate

2019 ◽  
Vol 11 (4) ◽  
pp. 1078 ◽  
Author(s):  
Carmen Calama-González ◽  
Rafael Suárez ◽  
Ángel León-Rodríguez ◽  
Simone Ferrari
Keyword(s):  
Solar Radiation ◽  
Environmental Quality ◽  
Indoor Environmental Quality ◽  
Cooling Systems ◽  
Incident Solar Radiation ◽  
Hot Climate ◽  
Shading Device ◽  
Operative Temperatures ◽  
Do So

In the Mediterranean climate, a large number of educational buildings suffer from discomfort due mostly to energy-deficient thermal envelopes and a lack of cooling systems. Impending climate change is expected to worsen overheating in classrooms, especially during heatwave periods. Therefore, the protection of window openings to reduce incident solar radiation while maintaining adequate indoor environmental quality must be considered a necessary key focus. The main objective of this research is to assess the influence of an egg-crate shading device on the indoor environmental quality of a classroom in Southern Spain. To do so, two classrooms—with and without this shading device—were simultaneously monitored over a whole year. The implementation of an egg-crate shading device allowed for a significant reduction of the incident solar radiation, both in summer and mid-season (around 45–50%), which objectively slightly conditioned indoor operative temperatures. Given the noticeable influence of the user patterns observed, indoor illuminance was also improved, as the rolling shutters tended to be opened at higher aperture levels.

Sign in / Sign up

Export Citation Format

Share Document