Conference Agenda

The SAM_Mollier toolkit, an innovative open-source project for creating and analyzing Mollier/Psychrometric processes, marks a significant leap in HVAC and thermodynamics fields. It utilizes advanced computational methods to determine essential thermodynamic properties crucial in HVAC system design and analysis. Integrated with the Grasshopper user interface, SAM_Mollier enhances user interaction and accessibility, proving invaluable for both industry professionals and academic educators.

The toolkit's workflow allows for the generation of Mollier points through diverse parameters like temperature, relative humidity, or humidity ratio etc. Once established, these points facilitate the querying and calculation of a wide array of variables in HVAC and thermodynamics, providing rapid access to crucial parameters. SAM_Mollier supports a variety of processes including Adiabatic Humidification, Heating, Heat Recovery, Isotermic Humidification, Mixing, Steam Humidification, Room, and Undefined Processes. For each process, the toolkit calculates sensible, latent, and total loads, including changes in enthalpy (Δh), humidity ratio (Δx), temperature (Δt), and Epsilon, representing process direction on chart (the enthalpy to humidity ratio proportion).

Uniquely, SAM_Mollier allow to draw Mollier Processes and Points in the Rhino environment on Mollier or Psychrometric Charts, contextualizing values visually. It also features a user-friendly UI for chart printing and data storage, enabling the saving of processes and points along with UI attributes like colors and tags in a JSON format for standardized data storage and sharing.

In recent years, concerns about indoor air quality (IAQ) in educational settings have intensified, particularly in the wake of the COVID-19 pandemic. The need for high-efficiency ventilation systems that balance IAQ with minimal energy consumption has become increasingly pressing. However, retrofitting existing buildings with mechanical ventilation solutions poses significant challenges, primarily due to spatial constraints limiting the installation of duct systems.

To address these challenges, a novel stand-alone ventilation system equipped with a heat recovery unit was developed and tested. Designed for direct installation within classrooms, this system bypasses the need for duct networks. Nevertheless, this approach introduced new challenges, primarily related to noise mitigation.

A tailored demand-controlled ventilation strategy was also developed to optimize the system's performance in educational settings. This research aimed to evaluate the performance of this innovative ventilation solution and assess its ability to overcome the identified challenges.

To achieve this, the ventilation units and control strategy were installed and tested in a functional classroom. Indoor air quality was monitored before and after the installation, providing valuable insights into the system's effectiveness.

The results demonstrate a substantial increase in teaching hours with acceptable air quality ranges, underscoring the potential of this novel ventilation solution to improve IAQ in educational buildings.

The treasure house of Horyu-ji Temple is a non-air-conditioned storage facility that houses the wall paintings at the main hall of Horyu-ji temple that damaged by fire in1949. Currently, mold has been observed on the wall paintings stored in the central room of the treasure house, especially on the wall paintings in the northeastern part of the central room. Temperature and humidity measurements in the treasure house reveal that the space near the floor in the northeastern part of the central room has higher relative humidity in summer due to lower temperatures than other locations in the room, which may increase the risk of mold growth.

The purpose of this study is to clarify the cause of locally low temperatures near the northeast floor of the central room by computational fluid dynamics analysis of the central room. The validity of the model is evaluated by comparing measured with calculated values. Then, based on the results of the temperature distribution and airflow analysis, the mechanism of the lower temperature near the floor behind the wall paintings is examined.

As a result, the mechanism of the lower temperature near the floor behind the wall paintings compared to the front side of the wall paintings is generally clear, although the cause of the particularly low near-floor space temperature in the northeast portion of the wall paintings-back space has not yet been clarified.

This study provides a method to reproduce the problematic distribution of temperature in the non-air-conditioned storage environment of cultural properties and to clarify the formation mechanism of temperature distribution.

Indoor air quality (IAQ) plays a crucial role in the health and well-being of building occupants, significantly influencing their concentration and overall comfort. This is especially important in densely populated spaces, such as classrooms, where a high concentration of individuals is sustained for extended periods. Poor IAQ in such environments can negatively affect cognitive performance and overall health, making it essential to prioritize clean, well-ventilated indoor spaces. Therefore, using ventilation systems to maintain acceptable indoor CO2 concentrations is of great importance. In this regard, applying mechanical ventilation systems is the most commonly adopted pathway. However, this route is associated with significant energy penalties, increasing the overall energy needs of buildings, hence their carbon footprint. In this vein, direct air capture (DAC) is emerging as a promising pathway for integration into buildings due to its potential to replace conventional mechanical ventilation systems and improve building sustainability.

The objective of this study is to evaluate the energy and economic feasibility of implementing DAC systems, both solid- and liquid-based DAC, instead of a controlled mechanical ventilation system in a condensed space classroom throughout the year. The heating, cooling and ventilation needs of the considered classroom are estimated using EnergyPlus software, and the remaining calculations are performed using Excel. Furthermore, the performance of each type of integrated DAC system is assessed taking into account different levels of capital and operating costs, energy prices and energy needs.

The results show that maintaining indoor thermal comfort and IAQ requires significant energy demand. However, when comparing the energy consumption of controlled mechanical ventilation and DAC, it becomes clear that the latter is more energy intensive, its energy consumption is 18–65% higher than that of the former. In economic terms, the obtained levelized cost of direct air capture (LCOD) is found in the range of 56–2500 $/tCO2, depending on the considered conditions. The outcomes of this research could be considered as a reference to identifying the best conditions for optimizing the performance of integrating DAC technology into the built environment, thereby decreasing buildings’ overall emissions, enhancing IAQ and minimizing HVAC energy consumption.

This paper compares two alternative models for investigating temperature and moisture distributions in air–air enthalpy exchangers, validated against experi-mental data. The first model is a 2D parallel-plate counterflow approach; the second is a 3D model that includes both counterflow and crossflow regions. In both models, the temperature and moisture fields in the exhaust and supply air streams are determined by coupling the governing heat and moisture transfer equations with velocity and pressure distributions from computational fluid dynamics. Moisture transfer through the semi-permeable membrane is modeled by applying a moisture-dependent resistance to vapor diffusion. Numerical simulations are performed using COMSOL Multiphysics. While the 2D model shows significant deviations from measured data, the 3D model demonstrates better agreement with experimental results.

Rural buildings comprise about 60% of the national building stock. These build-ings are naturally ventilated, carrying an inherent resilience to passively regulate indoor comfort in response to external climatic conditions. They also exhibit a greater resilience to withstand climate change when compared with dwellings adopting modern building materials. The performance of a building is typically examined based on indoor parameters such as temperature, humidity, air velocity, and air quality. So far, the building performance predominantly relied on tempera-ture. There is an increasing realisation and awareness of the concerns of rising moisture levels causing physiology. Parameters are affected by building proper-ties such as orientation, envelope design, window-to-wall ratio, aspect ratio, and many more in response to outdoor climatic conditions. With climate change hap-pening, response of building varies and there is a need to assess for the inertia (Resilience) of the buildings to meet the requirements of the occupant’s comfort.

The current study attempts to develop a framework for evaluating resilience using temperature and humidity in addition to relying on real-time data and simulation models, the methodology also tests a data science methodology to examine the in-fluence of building elements on resilience. Two building typologies, vernacular and conventional, in the village of Suggenahalli, have been studied. A Synergistic Analytical Framework was developed using the Apriori algorithm, using the con-cept of Association Rule Mining, and tested for existing building physics rela-tions. The results thus show the influence of building elements on the heat index. The vernacular dwelling’s resilience is affected by the low Air changes per hour, whereas in the conventional dwelling, it is the surface temperatures of roof.