Composite Climate Of India Research Articles

Bamboo in Contemporary Architecture: A Composite Climate in India

The rapid pace of growth requires the creation of appropriate space through infrastructure development. However, it's crucial to prioritize environmental considerations and additional construction's necessity. Bamboo, a versatile and sustainable material, holds immense architectural potential, especially in regions like Central India and Uttar Pradesh (UP) where it is abundantly available. To maximize the use of locally available bamboo in India's composite climate, investigate its properties, address usage challenges, and assess its potential as a sustainable material.Bamboo can be used structurally and non-structurally. Dendrocalmus strictus, Bambusa Bamboos, and Bambusa Balcoa are the locally available species that can be grown in local regions. Can be used for making temporary toilets near rivers, and sitting spaces that can be changed after 15 years. Can be used in making facades as well as interior walls.

Impact of indoor thermal environment on human thermal comfort, psychological response, and performance during winter in Jaipur, India

It is crucial to investigate the effects of indoor thermal environmental conditions on human performance, especially in India, during the winter when there is a significant need for space heating to maintain human comfort conditions. The present study was conducted in a controlled climate during winter, with 96 participants exposed to four air temperatures: 15 °C, 18 °C, 21 °C, and 24 °C. Participant's thermal comfort, emotion, and self-rated workload were assessed using a subjective questionnaire, while their performance was quantitatively evaluated using a neurobehavioral test. The data was analyzed to establish how the various thermal environmental factors influence performance, workload, emotion, and thermal sensations. The results show that the highest performance within the experimental thermal environmental conditions was observed when the thermal sensation ranges from neutral to slightly warm (+0.20) at the 23.5 °C mean standard effective temperature. At the same sensation, the occupant's mood disturbance and the mental workload for completing the task were minimal. These results would be helpful for facility managers of buildings by giving them insight into the impact of under or over-heating spaces on occupant performance during winter in the composite climate of India.

Development and optimization of kinetic façade system for the improvement of visual comfort in an office building at Gurugram, India

In a built space, the visual comfort is an important factor. It depends on the exterior environmental conditions. In general, the daylight has a positive effect on the human behaviours and circadian rhythm. Also, the occupants with a great visual connect with outdoors achieve high productivity. The occupants tend to use shading devices based on the local conditions and not based on future weather conditions. In this background, the kinetic facades provide a higher degree of manipulation thus providing a defined control over the daylight. For this reason, the kinetic façade systems remain a potential element to significantly increase the visual comfort. The kinetic façade optimization studies in the composite climate of India can provide valuable feedbacks in improving such systems for providing visual comfort in the built environment. The focus of the study is to evaluate the performance of kinetic shading systems in terms of enhancing the visual comfort in a composite climate.

Thermal performance of indirect green façade in composite climate of India

Many experimental and theoretical studies have shown that green facades can increase the thermal efficiency of a building's façade. Previous field research has focused on humid subtropical and tropical climates and the Mediterranean climate. There has been no research directed at the Indian climates. Moreover, the studies have evaluated microclimate and inside surface or ambient temperatures; however, whether its application creates a comfortable environment is yet to be found. A real-time study was performed to assess the effect of indirect green facade systems on the glazed facade to evaluate thermal comfort in India's composite climate (Hot semi-arid climate Bsh). Two glazed facades were examined: one with a green screen of Bengal clock vine and the other bare to serve as the base case. The temperatures on the southwest-oriented green façades were up to 8.1°C lower than the respective temperatures of the uncovered façade. In summer, the nighttime temperatures for the vegetated façade were up to 5.1°C higher than those for the base facade. No significant insulating effect in the cold season was observed. The highest reduction was seen between 2 p.m. and 6 p.m., implying the relation with high solar radiation during these hours in the southwest orientation. While the green facade helped lower building temperatures, it also raised relative humidity, making an uncomfortable indoor thermal environment. The study also aimed to find the appropriate distance to install a green façade. Although a green façade controls temperature, the study finds that a proper distance between greenery and the facade surface improves the system's thermal performance. According to the study, installing a green facade with more than 150 mm distance between the greenery system and the façade surface is optimum in New Delhi's composite climate. The study's findings try to fill the gap of the impact of green facades in the Indian climate to see its applicability on a larger scale; however, the results show increased discomfort with higher relative humidity as the climate changes from dry to humid.

Design and Optimization of Energy Consumption for a Low-Rise Building With Seasonal Variations Under Composite Climate of India

Abstract The need for maintaining thermal comfort conditions inside the building is a significant contributor to the total energy requirements of the buildings. Thus far, limited research has offered some strategies to mitigate the effect of ambient conditions on the thermal comfort and the building energy requirements for composite climatic zone in India. In order to address this problem, this study was conducted to evaluate and analyze the impacts of four different passive design strategies, i.e., insulation, cool roof, phase change material (PCM) thermal storage system, and shading, on thermal comfort and energy demand in the two-storey building situated in the composite climate zone of Delhi, India. The results obtained by numerical simulation for four different cities, i.e., Delhi, Jaipur, Lucknow, and Indore, have been compared to study the effect of local climatic and seasonal variations within the composite climatic zones. The simulations were conducted using the Design Builder software to capture results for one year. The results indicate that no single passive design strategy is sufficient to maintain comfortable conditions inside the building. The cool roof provides significant benefits in combination with other passive technologies in all seasons except for December, January, and February. The combination of insulation and PCM is useful for winter conditions. Energy saving of up to 20.5% is possible using the combination of all four passive strategies, whereas the cool roof alone gives an 18% reduction in energy load. The PCM with a melting point of about 32 °C is suggested for the cities under study.

Degradation and reliability analysis of photovoltaic modules after operating for 12 years: A case study with comparisons

The long-term performance monitoring and characterization of field-exposed solar photovoltaic (PV) modules are essential for efficient power generation. This paper is an attempt at performance evaluation of the amorphous silicon (a-si), Heterojunction Intrinsic Thin layer (HIT), and Multi-Crystalline (mc-si) technologies after twelve years of outdoor exposure in the composite climate of India. Characterization techniques such as Visual Inspection, Infra-Red (IR) Thermography, Electroluminescence (EL) Imagining, and Electrical characterization have been carried out. I–V measurements, power losses, current degradation, and voltage degradation calculations are carried out. The percentage of electrical decline is 8.61%, 2.73%, and 29.08%, for Isc, Voc, and PMP respectively in a-si solar modules. For HIT modules 1.97%, 0.68%, and 0.48% for Isc, Voc, and VMP respectively. Finally, for the mc-si PV modules, these are 3.76%, 0.5%, and 1.44% for Isc, Voc, and PMP respectively over 12 years. The average degradation rates are found to be 1.24%/year, 0.14%/year, and 1.50%/year for a-si, HIT, and mc-si modules respectively. The EL imagining of the a-si modules shows the localized shunt over the surface of the modules as well as disconnected cell interconnects whereas no such defects are over the m-ci and HIT modules.

Investigation on Subjects’ Seasonal Perception and Adaptive Actions in Naturally Ventilated Hostel Dormitories in the Composite Climate Zone of India

A seasonal adaptive thermal comfort study was done on university students in naturally ventilated dormitories in the composite climate zone of India. A total of 1462 responses were collected from the students during the field study spread over the autumn, winter, spring, and summer seasons of the academic year for 2018 and 2019. A “Right Here Right Now” type of surveying method was adopted, and the indoor thermal parameters were recorded simultaneously using high-grade instruments. The subjects’ mean thermal sensation (TS) was skewed towards a slightly cool feeling for the combined data. Most occupants preferred a cooler thermal environment during the summer season, while hostel residents desired a warmer temperature during autumn, winter, and spring seasons. During the summer season, the PMV−PPD model overestimated the subjects’ actual thermal sensation, while it underestimated the their thermal sensation in the winter season. The mean comfort temperature Tcomf was observed to be close to 27.1 (±4.65 °C) for the pooled data. Mean clo values of about 0.57 (±0.25), 0.98 (±0.12), 0.45 (±0.27), and 0.36 (±0.11) were recorded during the autumn, winter, spring, and summer seasons, respectively. Furthermore, switching on ceiling fans and opening doors and windows improved occupants’ thermal satisfaction during different seasons. The study results show the effective use of environmental controls and the role of thermal adaptation in enhancing the subjects/overall thermal satisfaction in the composite climate of India.

Performance analysis of single slope solar still under composite climate in India: Numerical simulation and thermal modeling approach

With increasing environmental concerns and depletion of fossil fuels, solar energy has grown significantly in producing potable water. 3D CAD model of solar still with single slope and single basin has been created. Multi-phase transient simulations were conducted in ANSYS FLUENT considering Delhi Technological University's climatic conditions (28.7501°N, 77.1177°E). Simulation findings of basin water temperature, condensing glass cover temperature, freshwater productivity was validated with experimental results of solar still and were found to be in good agreement. Thermal models developed by Dunkle, Clark, Kumar and Tiwari, and Adhikari model were also applied to predict and validate the performance evaluation of solar still with utmost accuracy. Characteristic equation of solar still has also been developed where instantaneous efficiency is plotted against (Tw − Ta)/I(t) with the value of R2 being 0.96 and 0.97 for linear and quadratic regression equations. An acceptable error of 12.7% between simulated output and experimental results was found.

A building bio-climatic design tool incorporating passive strategies in residential dwellings design of composite climate of India

A building bio-climatic design tool incorporating passive strategies in residential dwellings design of composite climate of India

A building bio-climatic design tool incorporating passive strategies in residential dwellings design of composite climate of India

A building bio-climatic design tool incorporating passive strategies in residential dwellings design of composite climate of India

Ecological Footprint of Residential Buildings in Composite Climate of India—A Case Study

Buildings are accountable for waste generation, utilization of natural resources, and ecological contamination. The construction sector is one of the biggest consumers of resources available naturally and is responsible for significant CO2 emissions on the planet. The effects of the buildings on the environment are commonly determined using Life Cycle Assessments (LCA). The investigation and comparison of the Life Cycle Ecological Footprint (LCEF) and Life Cycle Energy (LCE) of five residential buildings situated in the composite climatic zone of India is presented in this study. The utilization of resources (building materials) along with developing a mobile application and a generic model to choose low emission material is the uniqueness of this study. The utilization of eco-friendly building materials and how these are more efficient than conventional building materials are also discussed. In this investigation, the two approaches, (a) Life Cycle Energy Assessment (LCEA) and (b) Life Cycle Ecological Footprint (LCEF), are discussed to evaluate the impacts of building materials on the environment. The energy embedded due to the materials used in a building is calculated to demonstrate the prevalence of innovative construction techniques over traditional materials. The generic model developed to assess the LCEA of residential buildings in the composite climate of India and the other results show that the utilization of low-energy building materials brings about a significant decrease in the LCEF and the LCE of the buildings. The results are suitable for a similar typology of buildings elsewhere in different climatic zone as well. The MATLAB model presented will help researchers globally to follow-up or replicate the study in their country. The developed user-friendly mobile application will enhance the awareness related to energy, environment, ecology, and sustainable development in the general public. This study can help in understanding and thus reducing the ecological burden of building materials, eventually leading towards sustainable development.

Seasonal comfort temperature and occupant's adaptive behaviour in a naturally ventilated university workshop building under the composite climate of India

In the present research work, the authors investigated the seasonal thermal environment and thermal perception of university subjects in a naturally ventilated workshop building under the composite climate of India. Total 1460 subjective responses were collected during the field study in the year, 2019. Standard Effective Temperature (SET*) has been used as a rationally derived thermal comfort index to study the combined effects of air temperature, relative humidity and airspeed on perceived thermal sensation and occupant's preference under high metabolic rates. Probit analysis showed more than 80% of subjects were voting comfortable (±1 Thermal sensation votes) when SET* ranged between 25°C-33 °C. Seasonal mean comfort temperature varied more than 4.8 °C, while, preferred temperature was noted about 3 °C lower than their mean Griffiths comfort temperature. The adaptive relation developed from the collected database under high metabolic activities was compared with existing national and international comfort standards. The slope coefficient for adaptive relation was observed close to the adaptive model of ASHRAE Standard 55–2017 but lower than the National Building Code of India, 2016. Further, adaptive use of fans and windows were analyzed using logistic regression models and predicted about 80% of fans and windows were in operation at 30 °C. To confirm the adaptive mechanism, the interrelation of other contextual factors like gender, clothing insulation, airspeed, metabolic activities, etc. to thermal comfort expectations of subjects were also studied.

Adaptive thermal comfort study of workers in a mini-industrial unit during summer and winter season in a tropical country, India

Providing a comfortable thermal environment to workers for better health and productivity is one of the necessary conditions for sustainable industrial development. However, there is a dearth of field studies on the thermal comfort status and adaptation of workers in naturally ventilated industrial buildings across the world. Therefore, an adaptive thermal comfort field study in a mini-industrial unit factory, located in the composite climate of India, was conducted in the hot summer and cold winter seasons. Overall, 1276 valid subjective responses were collected from 325 factory workers during the field measurements and survey. We found a seasonal comfort temperature variation of more than 9.5°C with a mean comfort temperature of 32.2°C. The mean preferred temperature was observed about 2.5°C lower than their mean comfort temperature. The adaptive comfort relation suggested that surveyed factory workers had a high thermal adaptation owing to the combined effect of behavioural adjustments and elevated airspeed. A logistic regression analysis was carried out to predict the fan use behavior by the workers during the hot summer season. Since the study duration also lies in the COVID-19 pandemic period, an effort has been made to quantify the psychological and behavioural changes of workers due to the COVID-19 pandemic situation at their workplace through a questionnaire-based study.

Quantifying occupant's adaptive actions for controlling indoor environment in naturally ventilated buildings under composite climate of India

Occupant's adaptive actions (like windows opening, use of blinds and use of ceiling fan) have a strong effect on indoor environment. Only a few models of these actions exist and are solely based on indoor and outdoor thermal environments. This leads to large discrepancies between the actual and predicted indoor environment. There is no such study prevails in India and this highlights the need to investigate the occupant's local adaptive behaviour using the actual field data. The present study has developed adaptive behaviour models that relate window opening behaviour, blind use behaviour and fan use behaviour to the environment conditions in naturally ventilated buildings under the composite climate of India. Field measurements of adaptive behaviour actions and environmental conditions were conducted in thirty-one naturally ventilated buildings. The occupant's adaptive behaviour models were thus governed by various explanatory variables. In window opening behaviour model, the indoor and outdoor air temperatures, indoor air velocity, indoor lighting level and indoor CO2 were important governing variables. In blind use behaviour model, the indoor lighting level, indoor air velocity and window state were significant governing variables and in fan use behaviour model, the indoor air temperature, indoor air velocity and window and blind states were the most influencing variables. The occupant's adaptive actions were mostly governed by the pursuit of comfort and primarily driven based on the change in indoor environment rather than outdoors. Occupant's behaviour patterns of adaptive controls use were consistent with the literature and can be used for simulating the built environment in naturally ventilated buildings.

Thermal performance and comfort assessment of U-shape and helical shape earth-air heat exchanger in India

Earth Air Tunnel Heat Exchanger (EATHE) systems are not so much popular in India because of restricted accessibility of ground space in majority of residential and commercial sector. In the present article, thermal performance of newly designed helical shaped EATHE system has been compared with conventional U–shaped EATHE system by keeping similar geometrical and operational configuration for the summer (April–June) and winter (December–February), respectively. In this regard, therefore, numerical model of both EATHE systems have been designed and experimentally validated. The thermal performance of both EATHE systems has been compared in terms of outlet air temperature and effectiveness. The present numerical study suggested that the newly designed helical EATHE system exhibits better thermal performance with lower ground requirement as compared to conventional U-shaped EATHE system. To evaluate the thermal comfort potential of EATHE system in office buildings of India, composite climate specific adaptive thermal comfort boundaries has been used. The detailed thermal performance behaviour of the EATHE system suggests that an additional 80% of the time; ambient air conditions became thermally comfortable during peak summer season. In addition, analysis of the results revealed that EATHE system has more potential during heating operation mode to maintain indoor comfort in winter season of composite climate in India.

THERMAL PERFORMANCE EVALUATION OF GREEN LIVING WALLS IN COMPOSITE CLIMATE

Purpose of the study: Due to high solar radiation and extreme heat gain in composite climates, the envelope or the façade of the building becomes an essential part to modulate the heat transfer and temperature in the indoor environment. A passive sustainable approach to tackle heat gain is by adopting green living facades as the exterior skin. The objective of this research is to identify the potential of green living walls in modulating temperature and relative humidity in the composite climate of India.
 Methodology: This research is based on data collection in the form of a Case Study. The paper evaluates the difference of variation in temperature and relative humidity of two façade samples of the same building, one with a “green living facade” and one without it.
 Main Findings: The research aimed to justify that a green living facade may act as a passive strategy for composite climates. The result demonstrated that there is a significant temperature reduction between the ambient air temperature and indoor room temperature. The result also showed a notable change between ambient air temperature and the gap between the green living façade and the surface of the wall.
 Implications: Significant drop in indoor ambient temperature in composite climate may save energy for cooling or heating demands.
 Application of this study: This is a pilot study in order to carry out the main study for a similar application in order to categorize this as a passive sustainable façade strategy.
 Novelty/Originality of this study: The study is one of its kind attempt to investigate the impact of vertical green walls on thermal comfort in the composite climate of India.

Performance evaluation of photovoltaic double-skin facade with forced ventilation in the composite climate

Photovoltaic double-skin façades (PV-DSF) are a popular solution to reduce the energy consumption of buildings from the last few years. Many research groups are attempting to devise the method to manage the heat ingress in the built system through the PV-DSF system. In the present article, the surface temperature of the PV module and heat ingress in the built system is controlled through forced ventilation. The proposed system is evaluated for a range of air cavities and air velocities in the composite climate of India. The results indicated that the right combination of air cavity and air velocity could significantly reduce the solar heat gain coefficient and improve the power output of the PV system. The results show that for a naturally ventilated system, an increase in the air cavity from 50 mm to 250 mm yields a 12% reduction in SHGC. Likewise, a forced ventilated system exhibited a 19.24% reduction in SHGC for a 200 mm air cavity at an air velocity of 5 m/s. A forced ventilated system of 200 mm air cavity and flow velocity 5 m/s had 36% less SHGC than naturally ventilated of the same air cavity. The lower surface temperature of PV panels yielded improved power output due to continuous heat removal. The impact of forced ventilation on energy performance is found significant as compared to natural ventilation. This study manifested that forced ventilation in the PV-DSF system could cover a substantial share in the total energy consumption of the building.

Impact assessment of air velocity on thermal comfort in composite climate of India

Thermal adaptation plays crucial role in energy efficient operation of buildings without compromising with human thermal comfort. Elevated air velocity is commonly desired to restore comfort requirements at higher temperatures especially in NV and MM buildings located in tropical countries like India. This article is the systematic field study comprising a total of 4872 responses (1874 from NV buildings and 2998 from MM buildings) collected over a period of six years (2011–2017) during summer and moderate seasons under composite climate of Jaipur (India). Subjects’ responses and concurrent field measurements were utilized to investigate the impact of elevated air velocity on indoor thermal comfort. This research is a first attempt of its kind that deals with graphical quantification of air velocity required to offset increased temperature and follows similar approach as presented in ISO 7730. A redefined air velocity offset chart for Indian subjects working in office buildings has been proposed using the evidences (i.e. comfort expectations, preferences and local adaptation) collected from actual field observations. Thus, the offset in comfort operative temperature from base value of 28.04 °C and 26.93 °C for NV and MM buildings were obtained to be 4.78 °C and 4.24 °C, respectively for the elevated air velocity of 1.5 m/s.

Natural Ventilation Design: Predicted and Measured Performance of a Hostel Building in Composite Climate of India

Natural ventilation is recognized for improving the thermal comfort of the built environment and indoor air quality. It provides comfortable conditions for building occupants and reduces energy consumption for air-conditioning. Therefore, it is important to study and explore effective means of ventilation to improve the building designs. This study investigates the thermal comfort of a naturally ventilated hostel operational building in the composite climate of Jaipur, India using Computational Fluid Dynamics (CFD) simulation tool ‘Cradle scSTREAM’. A 3D building model has been developed to analyze the thermal comfort for different natural ventilation strategies with advanced mesh algorithms which generate fewer mesh elements and maintain good mesh quality. A field study was carried out to collect the actual data and to validate the model which was further used to evaluate the thermal comfort range based on the ASHRAE-55 standard. Several design strategies have been applied to enhance thermal comfort. It was found that an increase in air velocity up to 0.5 m/s was achieved by Cross Ventilation while a drop of 2.0–2.5°C in the air temperature was found using Night Ventilation. It can be stated that cross ventilation increases the air movement while night ventilation gives comparatively higher comfort regarding air temperature and relative humidity.

Occupant's thermal comfort expectations in naturally ventilated engineering workshop building: A case study at high metabolic rates

An adaptive thermal comfort study was carried for assessing the thermal comfort requirements of students working in naturally ventilated (NV) university workshop building in the composite climate of India over two seasons (Autumn and Winter). 1332 complete surveys, 516 and 816 from autumn and winter season, respectively were collected and analyzed. A maximum of 70% of subjects were found voting comfortable when indoor temperature varied from 28°C to 32°C. During the autumn season, the mean comfort temperature was about 5°C higher than the winter season. Also, female subjects had about 1.5°C higher comfort temperature compared to male subjects. Further, an attempt has been made to present an adaptive model for university students engaged in activity corresponding to machine work. The results were also compared with international thermal comfort standards. The results showed that students are more sensitive towards the fluctuations of outdoor conditions compared to the subjects in office and residential buildings. Moreover, subjects have shown better thermal adaptability towards prevailing mild cold climatic conditions through behavioural and clothing adjustments.