BURA Collection:

The influence of thermal radiation absorption on the interaction of transient transfer processes for a water droplet evaporating in a high-temperature gas flow

2026-05-14T00:00:00Z

Title: The influence of thermal radiation absorption on the interaction of transient transfer processes for a water droplet evaporating in a high-temperature gas flow Authors: Miliauskas, G; Maziukiene, M; Poškas, R; Puida, E; Jouhara, H Abstract: This work presents a study of transient transfer processes of water droplets evaporating in flue gas, including spectral radiation absorption and droplet slip. The results of numerical modelling of condensation, transitional and equilibrium evaporation regimes of water droplets in flue gas at temperatures ranging from 633 to 1833 K are presented. The modelled radiative transfer is based on geometrical optics theory. Convective heating and evaporation of the droplet are defined by the empirical Clift correlation for Reynolds numbers Re < 400. The interaction between transient processes and the dependence of the physical and optical spectral properties of a warming droplet on temperature are taken into account. The numerical iterative scheme defining the average instantaneous temperature of the droplet’s surface and working according to the fastest descent method is based on the balance of heat fluxes. The influence of Stefan flow, evaluated by the Spalding heat- and mass-transfer parameters, is made universal for different droplet phase change regimes by carefully assessing the dynamics of the temperature gradient within the droplet. It was verified that the competing effects of droplet slipping and the absorption of radiation are essential for the interaction between droplet transfer processes. The internal heat transfer in a droplet is affected by absorbed radiation and influenced by water circulation. Due to the effect of absorbed radiation, the evaporation rate of a large water droplet more than doubles in flue gas at 818 K and increases up to fourfold at 1133 K. These simulation results agree with the experimental data.

Intelligent Data-Driven Fuzzy Logic Control for Demand-Responsive Operation of Hybrid Geothermal Heat Pump Systems

2026-04-20T00:00:00Z

Title: Intelligent Data-Driven Fuzzy Logic Control for Demand-Responsive Operation of Hybrid Geothermal Heat Pump Systems Authors: Katchasuwanmanee, K; Pipatnawakit, S; Cheng, K; Kerdphol, T Abstract: Internal thermal load fluctuations and variations in occupant density affect the performance of Hybrid Geothermal Heat Pump (HGHP) systems. Traditional control strategies cannot provide the rapid adjustments needed to operate efficiently in real time and can be inefficient, leading to increased energy consumption and reduced thermal comfort. A data-driven fuzzy logic control framework is developed in this paper to dynamically adjust the performance of an HGHP system in real time as a function of occupancy and environmental conditions (e.g., temperature and humidity differences). The controller analyzes input data related to real-time outdoor ambient conditions like temperature, humidity and occupied spaces; a real-time flow sensor attached to the occupants of the building (a count of the number of occupants currently in each occupied space); and the coefficient of performance (COP) of the HGHP system, and uses the analysis to generate a “smart” control decision for the following device types: variable speed drive (VSD), fan number, operating modes, system control and valve positions. The controller also controls the overall system. The model was developed and simulated in MATLAB Simulink®, with realistic system parameters, and validated and calibrated using operational data from an HGHP system at a university, based on operating conditions. The simulation results indicate that our fuzzy controller achieves higher energy efficiency for thermal comfort than traditional thermostat-based controls, with COP improvements ranging from 7.36% to 11.76% and power consumption reductions between 4.13% and 8.55% across various occupancy scenarios. The improved COP also demonstrates the device’s responsiveness and effectiveness, even under frequent changes in occupancy patterns (dynamic occupancy), making it suitable for use in automated climate control systems in modern buildings. Description: Data Availability Statement: The original contributions presented in this study are included in the article. Further inquiries can be directed to the corresponding author.

Investigation of Electrical Discharge Machining Micro Holes in CoCrFeNiZr₀.₅ Eutectic High Entropy Alloys

2026-05-11T00:00:00Z

Title: Investigation of Electrical Discharge Machining Micro Holes in CoCrFeNiZr₀.₅ Eutectic High Entropy Alloys Authors: Fan, Q; Liu, L; Su, G; Zhang, C; Zhu, M; Cheng, K Abstract: As one of the most promising new materials in the field of materials science, high-entropy alloys (HEAs) have attracted widespread attention due to the unique structure, exceptional properties and engineering performance, and complex composition. The CoCrFeNiZr₀.₅ eutectic high-entropy alloys (EHEAs) exhibits excellent high-temperature thermal stability, ductility, creep resistance, and corrosion resistance, demonstrating great potential for applications in marine equipment. This paper explores the engineering feasibility of electrical discharge machining (EDM) of CoCrFeNiZr₀.₅ EHEAs and investigates the EDM of micro-holes using a hollow copper electrode on a CNC EDM drilling machine under various machining parameters, including different gap voltage, pulse-on time, pulse-off time, and pulse amplifier settings. The effects of these parameters on the inlet diameter, outlet diameter, and recast layer of the micro holes are analyzed. The optimal micro-hole machining parameters are determined by comprehensively considering machining efficiency and electrode wear: gap voltage of 33 V, pulse-on time of 3 μs, pulse-off time of 1 μs, and pulse amplifier output of 3 A. Adopting the parameters to process a button ingot sample with a depth of 5 mm, it was found that the machining speed is 7.79 mm/min and the electrode wear is 1 cm. This research renders the foundation for further development and engineering application of CoCrFeNiZr₀.₅ EHEAs in the context of high-value material design and manufacturing. Description: Data Availability Statement: The original contributions presented in this study are included in the article. Further inquiries can be directed to the corresponding author.

From corporate greenhouse gas inventories to design-relevant LCAs: an integrated framework for industrial decarbonization

2026-04-27T00:00:00Z

Title: From corporate greenhouse gas inventories to design-relevant LCAs: an integrated framework for industrial decarbonization Authors: Don Merenchige, UAW; Wang, B; Ji, S Abstract: Purpose: Global decarbonization goals demand accurate and transparent greenhouse gas (GHG) accounting across both organizational and product levels. However, existing frameworks such as the GHG Protocol, ISO-based standards, and product-level approaches like Product Carbon Footprint (PCF) and Life Cycle Assessment (LCA) are often applied in isolation, with limited operational integration for product design-oriented decision-making. This study develops and empirically validates an integrated framework linking organizational GHG inventories with product-level LCAs to enhance emission traceability, hotspot identification, and life cycle-based design support while strengthening methodological rigor and transparency. Methods: The proposed framework integrates the methodological principles of the GHG Protocol and ISO 14064–1 for organizational reporting, along with ISO 14040/44 and ISO 14067 for product-level assessment, within a unified structure. Implemented through an Excel-based tool, it systematizes activity data collection, GHG quantification, and allocation across Scopes 1–3 and product life cycle stages. The framework was tested using operational data from an automotive component manufacturer, which converted corporate inventories into product-level life cycle inventory (LCI) datasets. Robustness was evaluated through qualitative uncertainty assessment and quantitative sensitivity analysis. Results and discussion: Scope 3 supply chain emissions were found to dominate the organizational footprint (>90%), primarily driven by raw material extraction and processing of steel and aluminium. Product-level results indicate an average carbon intensity of 7.43 kg CO2e per part, with over 80% of embodied emissions originating from upstream material flows. The framework improves data traceability between operational activities and product emissions, enabling systematic identification of hotspots across materials, transport, and manufacturing processes. Conclusions: The integrated framework addresses the long-standing divide between organizational GHG accounting and product-level LCA by providing a structured and adaptable approach that improves consistency between reporting and product development. By linking operational data with product-level insights, the framework supports both backward-looking emission inventories and forward-looking sustainability assessments. While demonstrated within an automotive manufacturing context, broader application depends on organizational data maturity and sector-specific conditions. Nevertheless, the framework provides practical decision support for low-carbon material selection and supply chain decarbonization, contributing to industrial progress toward net-zero and circular economy objectives. Description: Data availability: The data supporting the findings of this case study were provided by the participating organization under confidentiality agreements. As such, the data are not publicly available in accordance with the organization’s data disclosure policy.; Electronic supplementary material is available online at: https://link.springer.com/article/10.1007/s11367-026-02639-8#Sec42 .