Experimental Investigation of a Direct Evaporative Cooling System for Year-Round Thermal Management with Solar-Assisted Dryer

Building cooling is achieved by the extensive use of air conditioners. These mechanically driven devices provide thermal comfort by deteriorating the environment with increased energy consumption. To alleviate environmental degradation, the need for energy-efficient and eco-friendly systems for building cooling becomes essential. Evaporative cooling, a typical passive cooling technique, could meet the energy demand and global climatic issues. In conventional direct evaporative cooling, the sensible cooling of air is achieved by continuous water circulation over the cooling pad. Despite its simple operation, the problem of the pad material and water stagnation in the sump limits its usage. Moreover, the continuous pump operation increases the electrical energy consumption. In the present work, a porous material is used as the water storage medium eliminating the pump and sump. An experimental investigation is performed on the developed setup, and experiments are conducted for three different RH conditions (low, medium, and high) to assess the porous material’s ability as a cooling medium. Cooling capacity, effectiveness, and water evaporation rate are determined to evaluate the direct evaporative cooling system’s performance. The material that replaces the pump and sump is vermicompost due to its excellent water retention characteristics. There is no necessity to change material each time. However, the vermicompost is regenerated at the end of the experiment using a solar dryer. The passing of hot air over the vermicompost also avoids mould spores’ transmission, if any, present through the air. The results show that vermicompost produces an average temperature drop of 9.5°C during low RH conditions. Besides, vermicompost helps with the energy savings of 21.7% by eliminating the pump. Hence, vermicompost could be an alternate energy-efficient material to replace the pad-pump-sump of the conventional evaporative cooling system. Further, if this direct evaporative cooling system is integrated with solar-assisted drying of vermicompost, it is possible to provide a clean and sustainable indoor environment. This system could pave the way for year-round thermal management of building cooling applications with environmental safety

Influence Of Pcm Thermal Conductivity And Htf Velocity During Solidification Of Pcm Through The Free Cooling Concept – A Parametric Study

The thermal performance of a latent heat thermal energy storage (LHTES) system can be enhanced by incorporation of fins, metal matrices, lessing rings in the phase change material (PCM) encapsulation and by dispersion of high conductive nanomaterials in the PCM itself. Similarly, to increase the heat transfer to PCM, the surface convective heat transfer coefficient (‘h’) can be enhanced by increasing the heat transfer fluid (HTF) velocity (‘u’). However, it is important to know how much increase in PCM thermal conductivity (‘k’) and ‘h’ will be beneficial during the charging of PCM under real-time ambient conditions and when will we reach the margin of diminishing returns. Understanding these are the motivation of the present work which includes the parametric study of the impact of ‘k’ & ‘u’ on the charging of PCM (RT28HC) through free cooling concept under different operating conditions (two different HTF inlet temperature). The numerical results are validated using the experimental data and they both show good agreement with each other. The major inferences from the results are, i) increasing the PCM thermal conductivity reduces the charging duration of the LHTES system for both lower and higher HTF velocity (1 m/s and 8 m/s). However, reduction in charging duration while increasing ‘k’ is higher when the HTF inlet temperature is lower, ii) increasing the HTF velocity is beneficial only when the inlet HTF temperature is higher. For the case of lower HTF inlet temperature, the effect of increasing the HTF velocity is suppressed by the higher temperature driving potential between the HTF inlet temperature and the PCM phase change temperature. It is inferred from the parametric study that, among the three parameters considered (PCM thermal conductivity, HTF velocity, and HTF inlet temperature), HTF inlet temperature has the most influence on the charging of the PCM, followed by the PCM thermal conductivity and HTF velocity

Opportunities and challenges of PCM-to-air heat exchangers (PAHXs) for building free cooling applications—A comprehensive review

International audienc

GHG emission accounting and mitigation strategies to reduce the carbon footprint in conventional port activities – a case of the Port of Chennai

Ports as an industry account for ∼3% of the total greenhouse gas (GHG) emissions worldwide. The Port of Chennai, India, uses an enormous amount of electricity and diesel for intermodal transportation of goods and for other essential services. The inventory of GHG emissions in the Port of Chennai is made by accounting the various facilities of the port along with the housing colony and fishing harbor which come under the management of the Port of Chennai. Quantification of GHG emissions is made following the guidelines of the Intergovernmental Panel on Climate Change (IPCC) and World Port Climate Initiative (WPCI). The estimation of GHG emissions showed that 280,558 tonnes of CO2e/year was generated from the port and port-related facilities. Several GHG mitigation strategies and their impact are quantified and discussed. The technology suggestions presented in the paper will be very useful to plan effective mitigation strategies incorporating technological advancement and management policies

Systematic data mining-based framework to discover potential energy waste patterns in residential buildings

International audienc

Integrating compressed air energy storage with wind energy system – A review

- With an increasing capacity of wind energy globally, wind-driven Compressed Air Energy Storage (CAES) technology has gained significant momentum in recent years. However, unlike traditional CAES systems, a wind-driven CAES system operates with more frequent fluctuations due to the intermittent nature of wind power. Consequently, the design and operation of wind-driven CAES systems must address such a complex and dynamic behavior. Considering the growing interest in wind-driven CAES systems, a comprehensive and systematic review of the existing literature on their design and operational characteristics is appealing. Therefore, this study aims at filling this research gap by examining the existing literature on the configuration, sizing, and operation/scheduling of wind-driven CAES systems. This review also aims at highlighting the underlying assumptions and methodologies employed in previous studies on wind-driven CAES systems. Given the challenges faced by several CAES projects, which were discontinued due to geological and economic constraints, it is imperative to conduct comprehensive feasibility studies to support the development and implementation of wind-driven CAES systems. Additionally, there is a growing necessity to explore the feasibility of small-scale CAES systems, focusing on their potential to bolster energy security and resilience for small or remote communities in distributed energy systems. By examining the existing literature and highlighting the gaps in current research, a number of insights are provided serving as foundations for future investigations in this field

Analysis on the driving factors and patterns of window opening and closing behaviour in French households

International audienc

Computer modelling and experimental investigation of phase change hysteresis of PCMs: The state-of-the-art review

International audienc