Warm Climate Regions Research Articles

A field study on indoor environmental quality and energy savings of an office building integrated with underfloor air conditioning system in India

This study aimed to examine the real-time indoor environmental quality (IEQ) factors in an office space environment with a dedicated underfloor air conditioning system. Nevertheless, underfloor air distribution (UFAD) system buildings in India do not have reliable studies to record the impact of occupant perception and IEQ factors. This study was conducted in the UFAD office building during the peak monsoon period of 16th – 25th October 2019 in a warm and humid climate region of Mumbai, India. IEQ factors of indoor thermal, air quality, lighting, and noise comfort were examined using an occupant questionnaire survey for sensation, preference and overall acceptability, as well as physical measurements. Furthermore, energy consumption and energy utilization coefficient were determined at different room set-point temperatures. Four hundred and thirty-five responses were collected during the field study. The comfort zone temperature was obtained between 22.24–25.3 °C with near-zero (±0.5) tolerance range. Moreover, 80-95% of the occupants felt comfortable and acceptable within the thermal environment of the room set-point at 22-25 °C. Results showed that the real-time IEQ score was perceived between 0.663-0.846. The real-time IEQ score can be used as a building management strategy that simultaneously improves thermal comfort and indoor air quality.

In a warm climate, ventilation, indoor temperature and outdoor relative humidity have significant effects on Campylobacter spp. colonization in chicken broiler farms which can occur in only 2 days

A longitudinal study was conducted in five conventional broiler farms during a 2-year period to determine the dynamics of Campylobacter infection in a warm climate region (north-eastern Spain). Weekly sampling of 63 flocks was performed upon one-day-old chick placement, including animal and environmental samples. Campylobacter spp. detection was assessed by culture and non-culture methods. Environmental samples were also obtained from cleaned and disinfected houses prior to chick placement. Thirty-nine flocks (61.90%) became colonized during the growing period. First bird excreting Campylobacter was detected in 10-day-old chicks and the earliest a whole flock became positive was at 14 days of age, while the latest was at 39 days. Once Campylobacter was detected in chickens, the whole flock was colonized within 2–13 days. Campylobacter farm prevalence (positive flocks) ranged from 53.85% to 83.33% in four out of five farms, while the remaining farm showed a lower prevalence (38.5%). Logistic regression model showed that Campylobacter infection was more likely under higher minimal indoor temperature as well as at higher minimal outdoor relative humidity, characteristic of warm climates such as those from Mediterranean countries. Ventilation type was also significant (P = 0.021). No clear farm effect or seasonality were observed. Biosecurity improvements, specially at house level, are needed in broiler farms to prevent flock colonization and reduce the current high flock prevalence.

Pilot-Scale Vinification of Cabernet Sauvignon Using Combined Lactiplantibacillus plantarum and Saccharomyces cerevisiae to Achieve Wine Acidification.

Insufficient acidity in grape berries from warm climate regions has been exacerbated due to global warming, thereby becoming a major concern for winemaking. The wine lactic acid bacterium Lactiplantibacillus plantarum has potential to ameliorate wine acidity by producing lactic acid from hexose metabolism, but its impact on wine compositions and sensory outcomes is not well studied. Here, we evaluated acidification and fermentation performance of indigenous L. plantarum in two inoculation regimes (i.e., reverse inoculation and co-inoculation) by conducting pilot-scale vinification using Cabernet Sauvignon with low acidity. Important parameters of the bio-acidified wines, including fermentation kinetics, basic oenological parameters, volatile and sensory profile were compared to those in wines produced by single Saccharomyces cerevisiae with/without chemical acidification. Total titratable acidity in L. plantarum wines were either comparable or significantly higher compared to the chemical acidification control. Chemical profiling reviewed remarkable differences in certain organic acids and major volatile compounds, especially an up to a five-fold, six-fold, and nine-fold increase in lactic acid, ethyl lactate and isoamyl lactate, respectively. Changes in chemical compositions of the bio-acidified wines resulted in differentiated sensory perception compared to the control wines. Except having higher scores for “wine acidity”, the flavour profile of the bio-acidified wines was shifted towards “jammy fruit” and “butter” aromas. Together, these findings highlighted the applicability of using L. plantarum to induce biological acidification along with modulation of wine flavour.

Effect of balcony forms difference on indoor thermal environment and energy saving performance of multiple-dwelling house

By optimizing the design of the building envelope, it is possible to create a more comfortable and energy-efficient indoor environment for the occupants. However, due to environmental issues in high-density cities, open balconies might affect the health of occupants. The current research focuses on the effect of a single balcony form in different climates, which could be detrimental to the diversity of balcony designs. Therefore, it is necessary to re-examine the rationality of traditional Japanese open balconies in terms of building envelope design and living environment to optimize the indoor thermal environment and reduce the energy consumption of dwellings. Focusing on Kitakyushu, Japan, which is in a warm climate, this paper conducts a comprehensive comparative study of the effects of building envelope design for residential buildings, including balcony form, thermal insulation performance, room orientation, and the window-to-wall ratio of balcony facades. The results of the study indicate that 1) the closed balcony design is strongly applicable to houses in warm climate regions in winter; 2) closed balconies facing south have a more positive impact on the indoor thermal environment, and energy-saving performance than open balconies; 3) even closed balconies without insulation could achieve higher thermal environment gains than open balconies with insulation. Designing a special type of closed balcony for residences in winter is more energy-efficient than insulation. This study proposes architectural envelope designs that are adapted to specific environmental and climatic conditions. It contributes to providing residential designers with a measure of how to provide a comfortable residential thermal environment and energy efficiency for occupants through architectural envelope design.

Decarbonization of cooling of buildings

Global energy demand for space cooling is growing very fast. In the emerging economies, building construction is projected to be a very intense activity in the coming years. This would mainly be driven by increasing population, growing wealth, rising aspirations of an improved lifestyle and rapid pace of urbanization. These countries are mostly in tropical and warm climatic region. The prevailing temperatures in these countries make space cooling a necessity. This will trigger a dramatic increase in the demand for cooling. As a result, building energy consumption and related greenhouse gas (GHG) emissions will continue to rise at a very high rate. If immediate appropriate measures are not taken, the state of technologies and the GHG emissions will be locked in for many decades. This paper discusses the existing space cooling technologies and their suitability to provide comfort cooling in the context of warm and humid climates. The low carbon alternatives for space cooling have been reviewed, and the strategies that can be adopted to reduce cooling loads and carbon emissions have been deliberated. Building sector in warm and tropical climate has significant untapped potential, and therefore offers a potential means for decarbonization. Relevant policies adopted and implemented in a country will play the major role.

Exploring the microbiome, antibiotic resistance genes, mobile genetic element, and potential resistant pathogens in municipal wastewater treatment plants in Brazil

Wastewater treatment plants (WWTPs) have been widely investigated in Europe, Asia and North America regarding the occurrence and fate of antibiotic resistance (AR) elements, such as antibiotic resistance genes (ARGs), mobile genetic elements (MGEs) and antibiotic resistant bacteria and pathogens. However, monitoring data about AR elements in municipal WWTPs in Brazil are scarce. This study investigated the abundance of intI1, five ARGs (sul1, tetA, blaTEM, ermB and qnrB) and 16S rRNA in raw and treated wastewater of three WWTPs, using different sewage treatments named CAS (Conventional activated sludge), UASB/BTF (UASB followed by biological trickling filter) and MAS/UV (modified activated sludge with UV disinfection stage). Bacterial diversity and the presence of potentially pathogenic groups were also evaluated, and associations between genetic markers and the bacterial populations were presented. All WWTPs decreased the loads of genetic markers finally discharged to receiving water bodies and showed no evidence of being hotspots for antimicrobial resistance amplification in wastewater, since the abundances of intI1 and ARGs within the bacterial population were not increased in the treated effluents. UASB/BTF showed a similar performance to that of the CAS and MAS/UV, reinforcing the sanitary and environmental advantages of this biological treatment, widely applied for wastewater treatment in warm climate regions. Bacterial diversity and richness increased after treatments, and bacterial communities in wastewater samples differed due to catchment areas and treatment typologies. Potential pathogenic population underwent considerable decrease after the treatments; however, strong significant correlations with intI1 and ARGs revealed potential multidrug-resistant pathogenic bacteria (Aeromonas, Arcobacter, Enterobacter, Escherichia-Shigella, Stenotrophomonas and Streptococcus) in the treated effluents, although in reduced relative abundances. These are contributive results for understanding the fate of ARGs, MGEs and potential pathogenic bacteria after wastewater treatments, which might support actions to mitigate their release into Brazilian aquatic environments in the near future.

Impact of Different Morphological Characteristics of Residential Areas on Wind Movement: Case Study of Karşıyaka (Izmir)

Cities are warmer than their surrounding rural areas due to the urban heat island effect. The heat island effect occurs in urbanized areas in which structures such as buildings and roads are highly concentrated and green cover is limited. Extreme heat waves resulting from climate change also cause temperature increases in the urban environment. In addition, the urban heat island effect negatively affects the comfort of individuals living in cities and increases the amount of energy required for cooling, especially in warm climate regions. To reduce both the urban heat island effect and the need for cooling, it is necessary to consider wind movement during the urban planning process. Within this context, it is vital that spatial development decisions allow planned building groups to benefit from natural ventilation opportunities. The morphological features of buildings directly affect the available opportunities to use wind energy for passive cooling in urban areas. Therefore, it is necessary to determine which morphological parameters affect the building-wind relationship. This study presents an analysis of wind simulations made by modeling selected examples of actual residential areas to determine the effects of different morphological features on wind movement. Twelve residential areas located in the Karşıyaka District of İzmir Province were determined for analysis due to their distinct morphological characteristics. The results of the study revealed that the parameters that affect wind movement in urban areas are the array of the buildings, their density, the distances between them, their floor area ratio, and their height. With regard to the provision of wind movement, it was found that the detached housing type is the most advantageous for hot climate zones. In addition, increasing the distances between structures was found to have a positive effect on natural ventilation. However, when viewed at the scale of residential areas, building heights on wind movements in the residential areas depends on the other two parameters. The simulations created for this study show that all morphological features of the building group under analysis affect wind movement, both separately and in combination.

Research Progress in Imaging Technology for Assessing Quality in Wine Grapes and Seeds.

The chemical composition of wine grapes changes qualitatively and quantitatively during the ripening process. In addition to the sugar content, which determines the alcohol content of the wine, it is necessary to consider the phenolic composition of the grape skins and seeds to obtain quality red wines. In this work, some imaging techniques have been used for the comprehensive characterisation of the chemical composition of red grapes (cv. Tempranillo and cv. Syrah) grown in a warm-climate region during two seasons. In addition, and for the first time, mathematical models trained with laboratory images have been extrapolated for using in field images, obtaining interesting results. Determination coefficients of 0.90 for sugars, 0.73 for total phenols, and 0.73 for individual anthocyanins in grape skins have been achieved with a portable hyperspectral camera between 400 and 1000 nm, and 0.83 for total and individual phenols in grape seeds with a desktop hyperspectral camera between 900 and 1700 nm.

Agriculture Land Price Setting Systems, and Possible Directions for Their Updating

The aim of this article is to assess the effect of the applied land valuation system on the price of land, and as a consequence of the implied links to compare the valuation of soil units in Slovakia and the Czech Republic. In order to fulfil this objective, an econometric approach was chosen in the form of a hedonic price model, whereby the heteroscedastic corrected linear regression model was specifically applied. The estimated model shows a very high explanatory ability, together with a high parametric significance for most fictitious variables (land characteristics), and at the same time also fulfils the theoretical and logical consistency of general assumptions. From the results, it is evident that, in the case of Slovakia, ESEU [evaluated soil ecological unit] valuation is affected primarily by the climatic region and the main soil unit. When comparing the results of the effect of individual input factors on the price of land in the Czech Republic and Slovakia, it can be stated that the results are slightly different in the effect of certain factors. The characteristics of soils located in warm climatic regions with a valuable soil type of chernozem and low slope are significant and positively intensive factors.

Influence of aeration intermittency on nitrogen removal in a reactor with aerobic granular sludge treating wastewater

The process of aerobic granular sludge (AGS) has been considered an alternative of great interest for the tertiary wastewater treatment mainly due to the great capacity of granule densification, which makes the system very compact. The simultaneous nitrification and denitrification (SND) occurrence guarantees nitrogen removal at a high level of efficiency and biological phosphorus removal can be optimized in this arrangement with a single treatment stage in sequential batches. In this study, the general behavior of a sequential batch reactor (SBR)/AGS in wastewater treatment and the effect of the air supply regime on nitrogen removal were evaluated. A pilot scale system supplied by relatively high concentration wastewater in a warm climate region was set up over 525 days. The study was divided into three main phases. In Phase I, a cycle of 3 h of total duration and continuous aeration of the sludge was applied with high efficiency in the removal of soluble chemical oxygen demand (sCOD) from the wastewater, but excessive drag of total suspended solids (TSS) with the effluent persistently occurred throughout the cycle. Nitrification went well, but wastewater denitrification was only partial with a notorious and worrisome accumulation of nitrite. In Phase II, the total cycle duration was increased to 4 h, but this increase in the time available for the anoxic and aerobic reactions was not enough to control the problem and the nitrite and nitrate residuals remained high in the effluent. In Phase III, the implementation of an intermittent aeration regime led to the production of an effluent from the treatment system with ammoniacal nitrogen, nitrite and nitrate average concentrations of 4.3 mg N·L−1, 0.4 mg N·L−1 and 5.5 mg N·L−1, respectively. Surveys of concentration profiles were carried out over some batches and it was observed that denitrification occurs mostly simultaneously with nitrification during the aeration period. The general conclusion of this study is that the application of intermittency regime in the air supply of AGS is of great importance for the improvement of nitrogen removal in this process.

A high-quality chromosome-scale assembly of the centipedegrass [Eremochloa ophiuroides (Munro) Hack.] genome provides insights into chromosomal structural evolution and prostrate growth habit

Centipedegrass [Eremochloa ophiuroides (Munro) Hack.], a member of the Panicoideae subfamily, is one of the most important warm-season turfgrasses originating from China. This grass has an extremely developed prostrate growth habit and has been widely used in transitional and warm climatic regions. To better understand the genetic basis of important biological characteristics, such as prostrate growth and seed yield, in warm-season turfgrasses, we present a high-quality reference genome for centipedegrass and use PacBio, BioNano, and Hi-C technologies to anchor the 867.43 Mb genome assembly into nine pseudochromosomes, with a scaffold N50 of 86.05 Mb and 36,572 annotated genes. Centipedegrass was most closely related to sorghum and diverged from their common ancestor ~16.8 Mya. We detected a novel chromosome reshuffling event in centipedegrass, namely, the nest chromosome fusion event in which fusion of chromosomes 8 and 10 of sorghum into chromosome 3 of centipedegrass likely occurred after the divergence of centipedegrass from sorghum. The typical prostrate growth trait in centipedegrass may be linked to the expansion of candidate PROSTRATE GROWTH 1 (PROG1) genes on chromosome 2. Two orthologous genes of OsPROG1, EoPROG1, and EoPROG2, were confirmed to increase the stem number and decrease the stem angle in Arabidopsis. Collectively, our assembled reference genome of centipedegrass offers new knowledge and resources to dissect the genome evolution of Panicoideae and accelerate genome-assisted breeding and improvement of plant architecture in turf plants.

Thermal Simulation of a Screenhouse Proposed for Fruit and Vegetable Production in the Lowlands of Panama

In developing countries, open field agricultural production is highly vulnerable to biotic and abiotic factors limiting crop productivity, generating economic losses and affecting food security. Therefore, one of the strategies that can improve these production systems is the implementation of the crops under cover technically adapted to the climatic and socioeconomic conditions of each region. The objective of this research was to analyze the thermal behavior and airflow patterns of an insect-proof screenhouse through computational fluid dynamics simulations using a 3D model. The results obtained for the multiannual monthly climatic conditions of a warm climate region in Panama showed that the airflow velocities inside the structure were lower between 76.8 and 80.2% with respect to the external velocity. The most critical scenarios showed temperature differences below 2℃ inside the screenhouse with respect to the outside. This value can be considered low as compared to the behavior of naturally ventilated greenhouses.

Thermal Energy Performance Simulation of a Residential Building Retrofitted with Passive Design Strategies: A Case Study in Mexico

High energy consumption as a result of an inefficient design has both economic and environmental repercussions throughout the life cycle of a building. In Mexico, the residential sector is the third-largest final energy consumer, therefore improving the performance of existing buildings is considered an effective method in achieving energy savings. Moreover, in Mexico warm climate regions predominate, which impacts energy consumption. This article examines a linked, single-family house located in the hot-humid climate city of Villahermosa, Tabasco (México). DesignBuilder software was used to conduct the thermal energy performance simulation of the existing building (base case) and to evaluate the energy-saving potentials by implementing different passive design strategies. As a result, the annual electricity consumption of the base case decreased a maximum of 2.0% with the passive design strategy in exterior windows, 4.9% in walls and, 13.7% reduction in roofs, the latter being the enclosure with the greatest reduction achieved. Nevertheless, a final adaptation proposal with the passive design strategies, whose results represented the highest energy savings, accomplished a total reduction of 23.5% with a payback period of 5.8 years.

An adaptive thermal comfort model for naturally ventilated classrooms of technical institutions in Madurai

PurposeOccupants dwelling in hot climatic regions of India for a longer term are tolerable to high temperature levels than predicted by American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) standards. The purpose of this study is to evaluate the thermal sensations (TS) and neutral temperature of the occupants in naturally ventilated (NV) and air-conditioned (AC) classrooms of two technical institutions located in the same premises in the suburbs of Madurai. The main focus of this study is to understand the occupants’ behaviour in response to the thermal conditions of the educational buildings particularly in the warm and humid climatic zone of Madurai.Design/methodology/approachThis research collected data through field studies. The data included 383 survey questionnaires from NV classrooms and 285 from AC classrooms, as well as on-site measurements of interior and exterior weather conditions. The TS results show that the students preferred well-designed NV classrooms than AC classrooms. A new adaptive comfort equation derived from this study can be applied to NV classrooms in warm and humid climates where mean outdoor temperature exceeds 40°C.FindingsThe neutral temperature derived for NV classrooms in Madurai ranged from 29°C to 34°C. Thus, the occupants in the NV classrooms of the higher learning educational institutions in the warm and humid climatic region of Madurai can adapt well to higher indoor temperature levels than predicted by ASHRAE comfort levels with minimum adjustments.Research limitations/implicationsThe study was limited to only occupants in two premier higher learning technical educational institutions located in Madurai region within 5–10 km within the city limits to understand the implications of microclimate with respect to the urban context. Thus, further research is required to examine the tendency under local conditions in other regions beyond those applied to this study.Social implicationsThe findings of this study showed that occupants in higher learning educational intuitions in Madurai prefer NV classrooms than AC classrooms. Therefore, with rising demands of energy use for mechanical ventilation and the associated high cost for running AC buildings, architects should prioritize the design of energy efficient buildings through the optimal use of passive design strategies for ventilation and thermal comfort. This study gives a base data for architects to understand the adaptive limitations of occupants and design NV buildings that can promote natural ventilation and provide better thermal environments that can help increase the productivity of students.Originality/valueThis paper was an attempt to develop the adaptive comfort model for NV classrooms in Madurai regions. There has been no attempt to identify the adaptive comfort levels of occupants in higher learning technical educational institutions located in warm and humid climatic region of India.

Analysis of the Thermal Behavior of a New Structure of Protected Agriculture Established in a Region of Tropical Climate Conditions

Determining airflow patterns and their effect on the distribution of microclimate variables such as temperature is one of the most important activities in naturally ventilated protected agricultural structures. In tropical countries, this information is used by farmers and decision makers when defining climate management strategies and for crop-specific cultural work. The objective of this research was to implement a validated Computational Fluid Dynamics (CFD) model in 3D to determine the aerodynamic and thermal behavior of a new protected agricultural structure established in a warm climate region in the Dominican Republic. The numerical evaluation of the structure was carried out for the hours of the daytime period (6–17 h), the results found allowed to define that the CFD model generates satisfactory predictions of the variables evaluated. Additionally, it was found that airflow patterns are strongly affected by the presence of porous insect screens, which generate moderate velocity flows (<0.73 m s−1) inside the structure. It was also identified that the value of the average temperature inside the structure is directly related to the air flows, the level of radiation and the temperature of the outside environment.

Inorganic carbon limitation during nitrogen conversions in sponge-bed trickling filters for mainstream treatment of anaerobic effluent

Anaerobic sewage treatment is a proven technology in warm climate regions, and sponge-bed trickling filters (SBTFs) are an important post-treatment technology to remove residual organic carbon and nitrogen. Even though SBTFs can achieve a reasonably good effluent quality, further process optimization is hampered by a lack of mechanistic understanding of the factors influencing nitrogen removal, notably when it comes to mainstream anaerobically treated sewage. In this study, the factors that control the performance of SBTFs following anaerobic (i.e., UASB) reactors for sewage treatment were investigated. A demo-scale SBTF fed with anaerobically pre-treated sewage was monitored for 300 days, showing a median nitrification efficiency of 79% and a median total nitrogen removal efficiency of 26%. Heterotrophic denitrification was limited by the low organic carbon content of the anaerobic effluent. It was demonstrated that nitrification was impaired by a lack of inorganic carbon rather than by alkalinity limitation. To properly describe inorganic carbon limitation in models, bicarbonate was added as a state variable and sigmoidal kinetics were applied. The resulting model was able to capture the overall long-term experimental behaviour. There was no nitrite accumulation, which indicated that nitrite oxidizing bacteria were little or less affected by the inorganic carbon limitation. Overall, this study indicated the vital role of influent characteristics and operating conditions concerning nitrogen conversions in SBTFs treating anaerobic effluent, thus facilitating further process optimization.

Window to wall ratio and orientation effects on thermal performance of residential building: A case of Butwal Sub-Metropolis

The orientation and glazed surface area used for windows in a building have significant effects on its indoor thermal comfort and overall energy consumption. The increasing use of glazed windows and lack of consideration of orientation in building design have become a major problem in warm and humid regions as windows cover sensitive skin areas for the exchange of energy leading to increased solar gain inside the building. This paper describes the effect of the varied ‘area ratio of glazed window to the wall for different building orientations’ on the thermal performance of the residential building in a warm humid climatic region of Nepal. A typical residential building located in Kalikanagr of Butwal, the fast-urbanizing sub-metropolis of Western Nepal, was selected for the study from 18 houses surveyed using the purposive sampling method. Nine varying values of Window to Wall Ratio (WWR) of glazed façade ranging from 0.1 to 0.9 with a constant increment of 0.1 in north and south façades, and the change in the building orientations were considered for the detailed study. Altogether eighty different test scenarios including base case scenarios were created and annual thermal energy consumption was computed for each test scenario using the Autodesk Ecotect Analysis, 2011. Findings from the study showed that the south orientation is the most appropriate compared to the north-east for all WWR to reduce the building energy consumption and an increase in WWR also results in increased energy consumption. The study concludes the careful considerations of WWR and the south orientation during the designing of building will contribute to efficient energy consumption in residential buildings.

Liquefied natural gas re-gasification cold energy hybrid system integration in gas-steam combined cycle power plant model: Enhancement in power generation and performance

• Hybrid system integration that uses a secondary chilled water circuit is proposed. • Significant enhancement of power output occurs at higher ambient temperature. • The hybrid system produces higher cooling duty. • The efficiency gain is at best marginal and depends on the integration approach. The liquefied natural gas (LNG) cold energy utilization for inlet air cooling (IAC) to augment combined cycle power output is widely recognized as a feasible and sustainable alternative. However, issues with flexible operation and hybrid system integration still remain in warm climate region. To take the edge off from such kind of issues and to enhance the power generation and the performance, few possible opportunities are explored for a gas-steam combined cycle power plant (CCPP) with thermal integration of LNG re-gasification cold energy. Three integration approaches, such as 1st gas turbine IAC, 2nd condenser water cooling (CWC) in steam turbine cycle and 3rd combined approach of both IAC and CWC are proposed. Thermodynamic modeling and simulation-based method is adapted for CCPP model identification and thermodynamic performance comparison. Moreover, the results are established as a function of relative humidity and ambient temperature along with off design power generation of the proposed system. The result shows that the CCPP relative power improved from 1.01% to18.48% (for third integration approach) and 0.17% to 0.217% (for second integration approach), in the ambient temperature range of 13–45 °C and relative humidity of 90–40% respectively, compared to that of non-integrated CCPP. In third integration approach the relative efficiency enhancement is observed in the range of 0.05–0.40%, particularly in higher range of ambient conditions. In second integration approach the CCPP efficiency enhanced from 0.17% to 0.22% in ambient temperature range of 13–45 °C and relative humidity 40–90%.

Effect of Soil Management and Training System on Negroamaro Wine Aroma.

This study aimed to assess the impact of two soil managements and training systems on yield and wine aroma compounds of Negroamaro variety grown in a warm climate region (southern Italy). Cover crop (CC) and soil tillage (ST) as soil management, whilst bilateral Guyot (BG) and monolateral Guyot (MG) as training systems were compared. Free and bound volatile fractions were evaluated by GC-MS. ST and CC as well as BG and MG significantly affected yield parameters. In particular, yield was higher in ST and BG than in CC and MG, respectively; moreover, it was found to be positively influenced by interaction between BG and ST. Regarding aroma compounds, significant interactions between soil management and training system factors were observed. In case of free volatiles, the most positive interaction was found between BG and ST, whereas, for bound volatiles, the best interaction was represented by MG with both soil tillage and cover crop. Vine leaf area and development over vine growth stages along with water stress levels played an important role in determining the aroma profile as well as yield parameters. In conclusion, the training system significantly interacted with soil management and affected most of important aroma compounds in Negroamaro wine.

Numerical investigation of optimal wall materials for effective thermal performance in warm and hot climatic regions

Purpose Heat gain in buildings occurs due to heat transfer through the building fabric or envelope, especially the walls and roof. The purpose of this paper is to identify and recommend the suitable wall materials for better thermal performance in buildings in warm and hot climatic zones of India. As India lies between the tropic of cancer and the equator, the solar radiation from the sun falls more on the walls than the roofs of the buildings. Thus, it is imperative to protect the walls from heat gain to promote thermal comfort in naturally ventilated buildings and reduce the energy loads due to artificial cooling systems in air-conditioned buildings. Design/methodology/approach In this paper, an investigation of heat flow characteristics in steady-state and the transient state for five different uninsulated wall structures using computational fluid dynamics (CFD) software has been carried out. The climate conditions at Madurai, India have been considered for this study. Findings The findings of the study revealed that aerated autoclaved concrete (AAC) and hollow clay blocks (HCB) for external walls in naturally ventilated buildings in warm climatic regions could improve the building’s thermal performance index and reduce peak indoor operative temperature by about 6°C–7°C. The results of steady-state and transient state analysis were found to be in good agreement with the results of the reviewed literature. Research limitations/implications Over the past few decades, only very few architects and builders have been successful in influencing their clients to accept alternate materials such as AAC blocks, HCB, stabilized earth blocks, adobe blocks, fly-ash bricks as an alternate to conventional bricks in an attempt of highlighting their benefits, such as; materials that are easily available, more energy-efficient, can withstand the extreme weather conditions, promote thermal comfort and cost-effective. This paper provides strong evidence that AAC and HCB blocks are the most appropriate materials for improving the thermal performance of envelope walls in regions where the outdoor temperatures are above 40°C. Originality/value This paper has made an attempt to identify the appropriate wall materials for effective thermal performance in warm and hot climates. A comparative analysis between five different wall types under the existing solar conditions has been analyzed using CFD simulation study in steady-state and transient conditions under summer conditions and the appropriate wall materials have been suggested. There has been no attempt carried out so far to analyze the thermal performance of different walls using 24 h transient approach in CFD.