Penetration Of Solar Radiation Research Articles

Effects of Ice-Microstructure-Based Inherent Optical Properties Parameterization in the CICE Model

The constant inherent optical properties (IOPs) for sea ice currently applied in sea ice models do not realistically represent the dividing of shortwave radiative fluxes in sea ice and the ocean below it. Here we implement a parameterization of variable IOPs based on ice microstructures in the Los Alamos sea ice model, version 6.0 (CICE6) and investigate its effects on the simulation of the dividing of shortwave radiation and sea ice in the Arctic. Our sensitivity experiments indicate that variable IOP parameterization results in strong seasonal variation for the IOP parameters, typically reaching the seasonal maximum in the boreal summer. With such large differences, variable IOP parameterization leads to increased absorbed solar radiation at the surface and in the interior of Arctic sea ice relative to constant IOPs, up to ~3 W/m2, but decreased solar radiation penetrating into the ocean, up to ~5–6 W/m2. The changes in the dividing of shortwave fluxes in sea ice and the ocean below it induced by the variable IOPs have significant influence on Arctic sea ice thickness by modulating surface and bottom melting and frazil ice formation (increasing surface melting by ~16% and reducing bottom melting by ~11% in summer).

Experimental analysis of dust composition impact on Photovoltaic panel Performance: A case study

Solar Photovoltaic systems are greatly influenced by meteorological conditions of the surrounding area, dust is the most influencing one. Dust deposition on the surface of photovoltaic (PV) panel hinder the penetration of solar radiation to PV cells and eventually reduce the power production of PV system. To overcome dust-based power losses, frequent cleaning is required depending on geographical location, PV integration scheme and size of the PV power plant. In this manuscript, consequences of dust deposition on photovoltaic systems such as drop in radiation and output power operating are studied, and the optimal time interval for cleaning is determined. Airborne dust particles were collected for a month for morphological and meteorological characterization. The average mass concentrations of the sample are 187.63 μgm-3, showcasing an irregular distribution of dust particles having unlike shapes and sizes. In this study, the influence of dust deposition is quantified using temperature and insolation for clean and dirty PV panels. The overall performance of the PV system is studied based on a comparison of quantified and recorded data. Lastly, different cleaning methodologies are studied to procure the best ones. Power losses were brought down to 7% when PV panels were cleaned fortnightly, which is the most feasible interval in terms of balance between cleaning cost and energy wasted due to soiling.

Parametric control of multiple blinds to enhance daylighting performance in the dome building: Case study of a mosque building in Saudi Arabia

Clerestory windows encircling the dome are a common feature in mosque architecture. They serve the purpose of allowing daylight to penetrate the spacious interior from all directions through smaller windows compared to side-lit windows. However, maintaining the required uniform daylighting coverage throughout the day in buildings with different directions remains a challenge. The integration of advanced daylighting systems with dome geometry, coupled with parametric control, can significantly enhance daylighting performance. In this research, a novel approach and simplified integrated method for parametrically controlling a multiple blinds system with incremental slat angle in a mosque dome's drum are developed, whereby the blinds in each direction respond independently and parametrically to the sun's movement. Parametrically controlled blinds are installed on the windows around the mosque’s dome to maximize the utilization of daylight while preventing direct penetration of solar radiation. Then, the daylighting performance of parametrically controlled multiple blinds was compared to that of conventional blinds and unshaded windows in a typical Mosque in Saudi Arabia during the noon prayer time. The study found that the parametrically controlled blinds can dramatically enhance the daylight coverage inside the mosque from around 38% to 88% for an illuminance range of 150–500 lx, while protecting users from direct sunlight. Promisingly, the system revealed that it can protect worshippers from direct sunlight, minimize potential glare and provide visual comfort.

Smart double glazing integrated polymer dispersed liquid crystal for enhancing building's thermal performance in hot-arid climate

Polymer-dispersed liquid crystal glazing is an electrically activated smart switchable glazing that requires an AC power supply to become transparent and remains opaque without power. This dynamic feature, with multiple transparency states, is suitable for building in hot and arid climates. It can effectively reject unwanted solar energy, allowing visible light while contributing to building energy efficiency by reducing the carbon footprint. In this work, the PDLC glazing system was included with a low-e coated glass and this coupled system was investigated with two control approaches for residential buildings in hot arid climates. The first control is a standard On-Off operation based on the tenant preferences, while the second is able to set glazing transparencies according to the solar radiation intensity, in order to minimize the penetration of direct solar radiation and to provide daylighting and indoor privacy protection. The system is reversed to examine the proper positions and layer order in the glazing system. The proposed system demonstrates remarkable enhancements in indoor thermal performance, surpassing clear glass by 21 % in the south orientation and 25.5 % in the west orientation. Furthermore, when the PDLC is oriented towards the outdoor environment, the system achieves an impressive 53.9 % improvement in heat gain control compared to clear glass. Additionally, the system not only enables dynamic control over direct solar radiation but also offers efficient daylighting and indoor privacy protection.

Towards Sustainable Indoor Thermal Comfort in the Tropical Building Design: Comparative Performance Analysis of Fixed External Shading Elements and Differential Window Glass Thermal Properties

Tropical region is characterised by high outdoor solar radiation and temperature. These radiations penetrate into the interior particularly through the window glazing, thereby raising the indoor temperature with a resultant effect on high cooling energy demand (for comfortable indoor living condition). Of the identified three sustainable approaches towards inhibiting direct incoming indoor solar penetration in the tropical city of Ogbomoso, Nigeria, this study, through computer-based simulation technique, compared performance effectiveness of varying design interventions on the window composition/material adopted. Through multiple/iterative building performance simulation tool, DesignBuilder, the methodology involves virtual model of a three-bedroom residential building, typical of the prevailing building typology in the study area. This particular model served as the experimental control model. Three (3) variants of the control model, each with either externally mounted shading devices on the building envelope, or improved thermally resistant multilayer window glazing (i.e., double glazing) or low-emissivity coated window glazing material, were generated for individual performance effectiveness evaluation. All the four models were subjected to a twelve-month simulation cycle, to experience a year-round thermal conditions and evaluations individually. The results show that double-glazing window installation proved to be the most effective approach, with about 13.1 % improvement (i.e., solar radiation inhibition) on the indoor thermal gains. This is followed by the externally mounted shading devices (i.e., 11.1 % improvement) and the least inhibition (i.e., 5.0 %) was observed in the case of low-emissivity coated window glazing material. Adoption of double or more layers of glass panes in window fabrication for controlling indoor solar radiation penetration is therefore advised. Alternatively, integration of external window shading elements could be adopted. This study is directed towards reduction of cooling energy consumption in tropical buildings through efficient and sustainable indoor cooling mechanism capable of inhibiting solar gains into the building, with a focus on the performance roles and composition of windows in particular.

A model for the Arctic mixed layer circulation under a summertime lead: implications for the near-surface temperature maximum formation

Abstract. Leads in sea ice cover have been studied extensively because of the climatic relevance of the intense ocean–atmosphere heat exchange that occurs during winter. Leads are also preferential locations of heat exchange and melting in early summer, but their oceanography and climate relevance, if any, remains largely unexplored during summertime. In particular, the development of a near-surface temperature maximum (NSTM) layer typically 10–30 m deep under different Arctic basins has been observationally related to the penetration of solar radiation through the leads. These observations reveal that the concatenation of calm and wind events in the leads could facilitate the development of the NSTM layer. Using numerical modeling and an idealized framework, this study investigates the formation of the NSTM layer under a summer lead exposed to a combination of calm and moderate wind periods. During the calm period, solar heat accumulates in the upper layers under the lead. Near-surface convection cells are generated daily, extending from the lead sides to its center. Convection cells affect the heat storage in the mixed layer under the lead and the adjacent ice cap. A subsequent wind event (and corresponding ice drift) mixes and spreads fresh and cold meltwater into the warm layers near the surface. Surface mixing results in temperatures in the near-surface layers that are lower than in the deeper layers, where the impact of the surface stresses is weaker. Additionally, the warm waters initially located under the lead surface stretch and spread horizontally. Thus, an NSTM layer is formed. The study analyzes the sensitivity of the depth and temperature of the NSTM layer to buoyancy forcing, wind intensity, ice drift, stratification, and lead geometry. Numerical results suggest that the NSTM layer appears with moderate wind and ice drift and disappears when the wind intensity is higher than 9 m s−1. Depending on the background stratification, the calm period reinforces or becomes critical in NSTM layer formation. According to the results, ice drift is key to the development of the NSTM layer.

Cooling streams with riparian trees: Thermal regime depends on total solar radiation penetrating the canopy

AbstractRiparian planting is often recommended for stream restoration, notably to mitigate solar heating of stream waters. However, plant leaves shade photosynthetically active radiation (PAR, 400–700 nm) more efficiently than the near‐infrared (NIR, 700–3000 nm) wavelengths that comprise about half of incident solar radiation and so contribute equally to water heating. Total solar radiation (NIR + PAR) exposure at the reach scale is needed to avoid bias when predicting the thermal response of streams. In this article, we alert stream ecologists and riparian restorers to the water heating contribution of NIR and provide a means to account for both NIR and PAR in total solar radiation penetrating riparian canopies. We used spectral pyranometers to simultaneously measure total solar radiation and its NIR component under different tree canopies over a wide range of shade conditions as indexed by PAR exposure. Measurements were made during full overcast (diffuse lighting) conditions so as to ‘sample’ transmission of radiation through the complete canopy. The NIR proportion of sub‐canopy solar radiation increased steadily with increasing shade and was appreciably greater under willow than pine canopies, while NZ native broadleaf rainforest had intermediate (rather variable) NIR content. Our trend lines for different tree canopies permit total sub‐canopy solar radiation to be estimated from PAR exposure for unbiased modelling of stream thermal regimes.

Effect of roof modification on micro-climate of animal shed

A study was conducted to compare the effect of roof modification with use of polycarbonate plastic sheet and its variable height on micro-climate of growing dairy heifers. The experiment was carried out on three sheds for three seasons, viz. hot-dry (summer) season, hot-humid (rainy) season and winter season. In control group (C), loose housing system was followed and corrugated cemented sheets were used as roofing material. In T1, polycarbonate sheets were used as roofing material with fixed height. In T2, polycarbonate sheets were used as roofing material with adjustable height. Daily ambient temperature (°C), dry and wet bulb temperature outside the shed (macro-climate) and inside the shed (micro-climate), Relative Humidity and Temperature Humidity Index were being recorded twice a day at 9.00 am and 2: 30 pm for three continuous days at fortnightly interval. The average temperature of animal shed was significantly lower in T2 (27.30±0.10), followed by T1 (28.28±0.04) and C (29.46±0.16). In T2 lower temperature of shed than control was recorded during summer. Increasing the height of shed with ridge ventilation might have helped to dissipate heat easily in T2. The overall THI was significantly lower in T2 (76.50 ± 0.16) followed by T1 (77.91 ± 0.05) and higher in control (78.74 ± 0.25), which might be due to less penetration of solar radiation via reflective polycarbonate sheet and higher height of roof in T2. The micro-environment was more conducive and comfortable in T2 than control. Polycarbonate roofing with adjusted higher height may be a desirable choice for animal housing to mitigate heat stress in summer.

OTTV'S Assessment on Thermal Performance of High-Rise Apartment Buildings in Penang

This study evaluates the envelope thermal performance of high-rise apartment buildings in Malaysia, which are being largely dominated due to the high economic development and increased population. The evaluation was conducted using the Overall Thermal Transfer Value (OTTV), which is the key tool used in the Green Building Index to assess the Energy Efficiency of buildings. Different high-rise apartment buildings were selected with different architecture styles, to account for several periods of building construction. The OTTV value was calculated for the west-oriented façade of the selected buildings, which is considered as a critical orientation that receives high solar radiation. The results showed that four out of the five investigated buildings achieved the minimum requirements for the OTTV, i.e., less than 50 W/m². The maximum and minimum OTTV values with the buildings’ original design were 82.60 W/m² and 41.54 W/m², respectively. However, one of the buildings achieved a lower OTTV value with the installation of shading devices by the owners, i.e., decreased from 48.39 W/m² to 37.60 W/m². The solar radiation penetration through the fenestration was found to be the major contributor to the total OTTV, while it can be controlled by the shading devices. Besides, using dark paints increased the heat conduction through the opaque walls by more than double compared to light paints. This study shows that some design considerations, such as paint colour, shading devices, and glazing material, can have a great influence on the heat gain in buildings.

Heat tolerance, thermal equilibrium and environmental management strategies for dairy cows living in intertropical regions.

This review makes an attempt to characterize the physical attributes of heat tolerance, thermal equilibrium and thermal stress thresholds for dairy cows living in tropical environments, with a particular emphasis on pasture-based systems. Under such circumstances, the radiant heat load is the principal climatic factor that determines rates of heat and mass exchanges between cows and the environment. This fact may explain why simple mechanistic models based on air temperature and humidity are not adequately predicting thermal stress thresholds for cattle in tropical regions. To overcome this limitation, the Index of Thermal Stress for Cows (ITSC) and Index for the time spent in shade (ITS), which account for various sources of thermal radiation, were proposed to predict autonomous and behavioral thermoregulation of cows. Overall, the evolutionary adaptation of cattle in tropics favored animals that have cutaneous surface with a skin well protected against penetration of ultraviolet solar radiation (UV), covered by a coat surface with high thermal conductivity. For Holstein breed, although predominantly black animals absorb greater levels of short-wave solar radiation, they may present better protection of skin than white ones. However, dark-colored cows in tropical pastures have potential to absorb as much as 640 W m-2 of thermal radiation. This amount of heat load would require close to 1,300 g h -1 of cutaneous evaporative water loss through sweating to prevent increases to body temperature, where cows do not have access to shade. Cows are motivated to reduce time spent grazing and to seek shade when solar irradiance exceeds 550 W m-2, levels that in equatorial latitudes are likely to occur between 08:00 and 16:00h. This information may help producers improve the welfare of cows, as they can determine more comfortable hours for them to graze, for example, by employing nocturnal grazing. Over the daytime, cows should have access to areas with shade and this could include shade provided via solar panels, which has the potential to improve thermal comfort and sustainability of dairy production in tropical areas.

Effects of Ocean Chlorophyll on the Mode Water Subduction Rate in the Northwestern and Central Pacific Ocean

The effects of ocean chlorophyll on the mode water subduction rate in the subtropical mode water (STMW) and central mode water (CMW) in Pacific Ocean are investigated by performing two ocean-only experiments, using two different solar radiation penetration schemes, one with and one without chlorophyll effects. The biological impacts on mixed layer depth (MLD), upper ocean temperature and density are analyzed. Results show that the subduction rates of both STMW and CMW are increased with the effects of ocean chlorophyll. The increase in the subduction rate is mainly caused by the increased lateral induction term, which is related to larger MLD gradient in early spring in the chlorophyll experiment.

The internal melting of landfast sea ice in Prydz Bay, East Antarctica

Summertime internal melting of Antarctic sea ice is common due to the penetration of solar radiation below the snow and ice surface. We focus on the role of internal melting and heat conduction in generating gap layers within the ice. These often occur approximately 0.1 m below the ice surface. In a small-scale survey over land-fast sea ice in Prydz Bay, East Antarctica, we observed, for the first time, gap layers 0.6–1.0 m below the surface for both first-year ice and multi-year ice. A 1D snow/ice thermodynamic model successfully simulated snow and ice mass balance and the evolution of the gap layers. Their spatial distribution was largely controlled by snow thickness and ice thickness. A C-shaped ice temperature profile with the lowest values in the middle of the ice layer resulted in heat flux convergence causing downward progression of the internal melt layer. Multidecadal (1979–2019) seasonal simulations showed decreasing air temperature favored a postposed internal melting onset, reduced total internal melt, and delayed potential ice breakup, which indicated a higher chance for local coastal ice to be shifted from first-year ice to multi-year ice.

Simulation and Analysis of Influencing Factors of Pavement Thermal Environments in Guangzhou

Pavements are closely related to the livelihoods of urban residents as an important part of the urban road system. Based on the early field measurements of our team, we found that plant spacing, pavement orientation, and pavement material influence the pavement thermal environment. Our objective was to quantitatively evaluate the influence of various factors on pavements in Guangzhou along West Zhonghuan Road, Guangzhou University. Based on our team’s previous research, environment-met (ENVI-MET) numerical simulation software was used to simulate pavements under different road orientations, underlying surface materials, and plant distances. Quantitative analysis of the effects of different factor combinations on the temperature, humidity, wind speed, physiological equivalent temperature (PET), and radiant temperature (Tmrt) was performed. The results show that among the various factors affecting the thermal environment of pavement, street tree spacing was found to have the greatest effect on the thermal environment of pavement. The effect of direction is negligible; however, it has a significant effect on the wind speed. There was no significant difference in the air temperature and relative humidity between concrete and asphalt. The average air temperature of red floor tile was slightly lower than that of asphalt and concrete. Reducing the spacing of street trees can effectively reduce the penetration of direct solar radiation, physiological equivalent temperature (PET), and temperature (Tmrt) and improve pedestrian walking comfort. The results can serve as a reference for pavement design in Guangzhou and improve the wellbeing of citizens and promote environmental sustainability.

The characteristics of plant clusters influence on the cooling effect: A case study in a subtropical Island Park, China

Plant clusters planted in urban green spaces have a significant potential to improve the microclimate. To put this potential to the test, eleven plant clusters (20 m × 20 m) in size were selected as sample plots in Haitan Island, China. We measured the microclimate including air temperature, relative humidity, solar radiation, and wind speed on sunny days from 8:00–17:00. The data were collected from July to September 2020. The purpose of this study was to determine the relationship between plant cluster characteristics and microclimate to enhance tourists comfort. The findings indicated that eleven sample plots had eighteen tree species with four distinct plant functional types. The air temperature difference between the interior and exterior of the plant clusters was substantial and the cooling effect dTair ranged from 2.65% to 5.19%, while the reduction of solar radiation dSR was between 58.08% and 98.33%. Crown area, wind speed, relative humidity, and solar radiation all affected air temperature, as determined by Piecewise SEM analysis. The cooling effect was mostly affected by crown area, canopy density, wind speed, and solar radiation showing that canopy structure affected air temperature by altering solar radiation penetration. Meanwhile, leaf transpiration generated water vapor, which increased relative humidity and cooled the air. Quantitative data on the crown area and canopy density were provided so that forestry management practices can improve people’s comfort while in the area.

Development and Evaluation of Dust Cleaning System for a Solar PV Panel

The most promising application of solar energy is the conversion of solar energy into electrical energy by using solar photovoltaic (PV) panel. The performance of solar based PV panel is definitely influenced by the amount of solar radiation, which are reaching on the panel surface. Since the solar PV panels are operating in open atmosphere dust particles get deposited on their surfaces and most of the times they have to work in this condition. These deposited dust particles create a layer of dust particles over the panel surface which prevents the 100% penetration of solar radiation into the panel surface. Therefore, proper cleaning of the panel surface becomes very necessary. In order to improve the performance of the PV panel an automatic microcontroller driven dust cleaning technique is developed which is capable of removing the accumulated dust particles from the PV panel surface. Moreover, an experimental study has been performed to analyse the efficiency of this developed techn ique. The developed cleaning system showed an improvement of 27.98% in the output power of PV panel when compared to the dusty panel.

Growth of Sphagnum Riparium Contains the Signature of Short Wavelength UV-B Passing Through the Ozone Layer

It follows from the negative reaction of plant growth to UV-B that the wavelengths penetrating through the ozone layer, in contrast to the absorbed ones, should leave a specific signature in the form of growth inhibition. This signature is expected, for example, for peat mosses of the Sphagnum genus. To test this hypothesis, we studied the growth response of Sphagnum riparium Ångstr. to solar UV in the 200-310 nmrange, recorded outside the Earth’s atmosphere. It was found that wavelengths starting from 286 nm significantly inhibited the growth of Sphagnum, while shorter wavelengths hadno significant effect. It follows that wavelengths starting from 286 nm reach the Earth’s surface, while shorter ones are absorbed by the ozone layer. These data correspond to the physical concepts of the 286 nm limit for solar radiation penetration through the ozone layer. Based on the universal UVR8-dependent mechanism of UV-B reception in plants, we conclude that plants have potential as indicators for assessing the penetration of the shortest solar UV-B wavelengths through the ozone layer.
 Keywords: UV-B, 286 nm, Sphagnum, growing season, growth inhibition

Estimation of evapotranspiration in Eucalyptus plantation and mixed forests based on air temperature and humidity

Soil evaporation, Air temperature and humidity inside and outside the forest and river flows were continually monitored in eucalyptus plantations (EU) and coniferous broadleaved mixed forests (MFs) to investigate the reasons for the decreased runoff recorded in EU. The applicabilities of four estimation methods based on air temperature and humidity were evaluated and verified. Our results show that: (1) the average annual solar radiation penetration rate of the EU canopies was 1.75 times that of the MFs canopies, and temperatures were lower inside the two forests than outside the forests. The daily average temperatures inside the EU and MFs were 20.7 ℃ and 20.8 ℃, respectively, which were 1.5 ℃ and 1.4 ℃ lower than those outside the forests. The daily average relative humidity was 0.8% higher in the MFs than in the EU. (2) The evapotranspiration of EU and MFs accounted for 80.2% and 76.3% of the total rainfall respectively, of which the soil evaporation was 12.8% and 8.9% respectively, and the runoff production coefficients were 0.198 and 0.237 respectively. The main reason for the decrease of the EU production was that soil evaporation in EU was 43.8% higher than that in MFs. (3) The deviation of EU and MFs evapotranspiration (ET0) from the measured values was estimated by the ET0Valian(T, RH) and ET0Alt/rs(T, RH) methods as less than 10%. (4) Using the product of the extraterrestrial solar radiation and the surface solar emissivity of the forest instead of the extraterrestrial solar radiation in these four formulas, the variation trend of the estimated forest soil evaporation was highly similar to the measured value. ET0Valian(T, RH) and ET0Alt/rs(T, RH) had the highest accuracy in soil evaporation estimation (2.0–3.4% lower than the measured values). The results provide a theoretical basis for studying the ecohydrology of subtropical plantations in the Northern Hemisphere.

Facade control systems for optimal daylighting: A case of Kerala

Indoor environmental quality is one of the most important aspects to be considered while designing buildings. Design decisions taken to ensure indoor environmental quality depends upon the specific location, climate, form, orientation and materials used for the construction of the building. In addition to ensuring comfort and optimal occupant conditions, these design decisions also impact the overall energy consumption of the building. The design of the building envelope is of more importance in regions that receive a huge amount of solar radiation. Kerala, falling in the Tropical belt, have buildings designed (or supposed to be designed) with sufficient roofing/shading overhangs to avoid penetration of solar radiation, and direct glare towards the inside. Well-designed shading devices provide the best shading during overheated periods thus lesser heat gain or cooling load. The form of shading devices influences day-lighting inside the building. This paper intends to explore different types of shading devices and façade control systems, and their impact on daylighting inside a selected commercial building in Kerala. It concludes by identification of the most efficient design of the device in each type identified, through BIM modelling and lighting simulation, specific to the original building location, to ensure optimal daylighting while eliminating the undesirable effects of solar radiation.

Air Temperature and Humidity at the Bottom of Desert Wolf Spider Burrows Are Not Affected by Surface Conditions.

Simple SummaryWe investigated whether trapdoors, which small Negev Desert wolf spiders (Lycosa sp.) use to close their burrows, serve to maintain favorable conditions of temperature and humidity within them. We removed trapdoors from burrow entrances and monitored changes in temperature and relative humidity in their bottoms, where the spiders reside during the day. We also followed the behavioral responses of these spiders to trapdoor removal at different times of the day and in different seasons and monitored temperature and relative humidity in artificial burrows during summer mornings and at midday. At noon, air temperature at the bottom of open artificial burrows increased by less than 1 °C more than in covered ones, and total humidity remained constant, even though air temperature at the soil surface reached 55 °C when the burrow temperature was 35 °C. The relatively small increase in air temperature in uncovered burrows at midday was probably due to the penetration of direct solar radiation. Thus, it is evident that the presence of a trapdoor has a negligible effect on the microclimate at the bottom of these spiders’ burrows and its roles are more likely predator avoidance and prevention of flooding and stones and sand from falling in.Burrows are animal-built structures that can buffer their occupants against the vagaries of the weather and provide protection from predators. We investigated whether the trapdoors of wolf spider (Lycosa sp.; temporary working name "L. hyraculus") burrows in the Negev Desert serve to maintain favorable environmental conditions within the burrow by removing trapdoors and monitoring the ensuing temperature and relative humidity regime within them. We also monitored the behavioral responses of “L. hyraculus” to trapdoor removal at different times of the day and in different seasons. “L. hyraculus” often spun silk mesh in their burrow entrances in response to trapdoor removal during the day, possibly to deter diurnal predators. The frequency of web-spinning peaked on summer mornings, but spiders began spinning webs sooner after trapdoor removal later in the day. In addition, we monitored temperature and relative humidity in artificial burrows in the summer during the morning and at midday. At noon, air temperature (Ta) at the bottom of open burrows increased by <1 °C more than in covered burrows, but water vapor pressure in burrows did not change. The relatively small increase in Ta in uncovered burrows at midday can probably be ascribed to the penetration of direct solar radiation. Thus, air temperature and humidity at the bottom of the burrow are apparently decoupled from airflow at the surface.

Comprehensive building envelope optimization: Improving energy, daylight, and thermal comfort performance of the dwelling unit

The majority of the conducted researches in the past few years examined daylight and energy usage as the primary goals considering the specific parameters of the building envelope. Despite the great importance of interior thermal comfort and its substantial impact on other objectives, it rarely accounted as the third objective alongside energy and daylight performance. The current study presents a multi-objective optimization analysis evaluating Energy Usage Intensity (EUI), Useful Daylight Illuminance (UDI), and Predicted Percentage of Dissatisfaction (PPD) with a wide range of envelope parameters to clarify the relationships between the objectives and the parameters with objectives. The envelope variables include the wall and roof construction and insulation (type and thickness), skylight, Window-to-Wall Ratio (WWR), and external shading device (number, depth, and angle). The case study is a real-world duplex house modeled without simplification considering surrounding areas in a humid subtropical/Mediterranean climate. During the optimization process, 2600 solutions are generated, then the optimal solutions are selected for comparison purposes. The results emphasize the importance of the balance between parameters to provide efficient performance, particularly for the PPD. Accordingly, solar radiation penetration into interior places in cold months results in a lower PPD value. Furthermore, a correlation can be seen between parameters regarding daylight and energy distribution. The building insulation, wall construction, WWR, shading features, and skylight orientation are immensely influential on all three objectives. Compared with the original model, the balanced model indicates an improvement in the EUI, UDI, and PPD by 36%, nearly 5%, and 14%, respectively. The results of this investigation have the potential to be used in the early stage of design, refurbishment, and renovation cases.