http://bura.brunel.ac.uk/handle/2438/8625 Tue, 10 Mar 2026 16:31:50 GMT 2026-03-10T16:31:50Z http://bura.brunel.ac.uk/handle/2438/32952 Title: A social sustainability assessment of a newly developed solar thermal energy system for industrial integration Authors: Zafar, I; Stojceska, V; Rovira de Antonio, AJ; Abbas, R; Fernandez, JPS; Camara, JM; Kew, P; Naplocha, K; Tassou, S Abstract: The deployment of solar thermal energy (STE) systems plays a critical role in decarbonising industrial heat demand; however, their sustainability performance includes not only technical efficiency and environmental impacts but also social considerations across the supply chain. This study presents a comprehensive social sustainability assessment of a newly developed STE system focusing on the manufacturing stages of its main components: SunDial concentrator, a phase change material (PCM) thermal storage tank, and a control unit. Social risks were quantified using a database driven risk hour (RH) approach, across different impact categories. including health and safety (H&S), fair payment, excessive working time, gender equality and policy compliance. The data were collected using Social Hotspot Database (SHDB) software, which simulated social risk levels based on material quantities and countries of origin of system components. The results revealed that social risks are strongly dependent on country of origin and economic sector, rather than material quantity alone. The SunDial component manufactured in Spain demonstrated moderate H&S and gender inequality risks within the steel sector, while comparable components produced in Germany showed consistently low social risk levels. Similarly, manufacturing of PCM tank subcomponents in the Polish non-ferrous metals sector showed increased H&S risks, largely driven by high policy non-compliance and exposure to metal dust, while chemical production in the Netherlands showed substantially lower social risks due to stricter regulatory implementation. The findings highlight the importance of geographically and sector specific social assessments when sourcing components for renewable energy systems. Incorporating social sustainability metrics at early stages of design can guide responsible supply chain decisions, improving the overall sustainability performance and social acceptability of industrial STE technologies. Description: Highlights: • The social sustainability of an industrial solar thermal system is conducted. • The system consists of a SunDial, PCM storage tank, and control unit. • Supply-chain social risks are quantified using a risk-hour SHDB framework. • PCM storage components showed the highest social risk. • Manufacturing location strongly influences health, safety and labour risks.; Data availability: Data will be made available on request. Mon, 09 Feb 2026 00:00:00 GMT http://bura.brunel.ac.uk/handle/2438/32952 2026-02-09T00:00:00Z http://bura.brunel.ac.uk/handle/2438/32945 Title: Design of micro-channel based actively cooled thermal shields for ultra-high temperature applications Authors: Miranda, P; Agujetas, R; Montanero, JM; Nogales, FM; Sayma, A Abstract: In this study, novel designs of high-temperature thermal shields that can be actively cooled by circulating water through a bioinspired internal microchannel network are numerically evaluated. The level of cooling that can be achieved and the thermal stresses developed in the shield material are analysed using computational fluid dynamics and finite element modelling. From the comparative analysis of those results, design guidelines for the development of such actively cooled thermal shields (ACTS) are proposed: (i) channel design plays only a minor role on the coolant mass needed to produce a desired level of cooling but (ii) small channels around the regions of maximum temperature gradient and stress concentrators like sharp corners should be avoided to prevent cracking of the shield material; and (iii) high temperature tolerance and high thermal conductivity are key parameters for the shield material. Thus, ultra-high temperature ceramics (UHTC) such as ZrB2 appear to be optimal candidates for the additive fabrication of such ACTS elements, provided they can survive the thermal cycling without cracking. Water was confirmed as an excellent coolant for such an application, enabling the development of reusable solutions for aerospace re-entry shields, involving coolant masses that could become competitive against current single-use ablative shields. Similar systems could provide suitable thermal protection or heat exchange solutions in many other demanding industrial applications. Description: Data availability: Data will be made available on request. Thu, 26 Feb 2026 00:00:00 GMT http://bura.brunel.ac.uk/handle/2438/32945 2026-02-26T00:00:00Z http://bura.brunel.ac.uk/handle/2438/32842 Title: A comprehensive life cycle assessment of vacuum insulation panels (VIPs) for applications at up to 70 °C Authors: Raad, T; Singh, H; Sivan, S Abstract: This paper presents a comprehensive Life Cycle Assessment (LCA) of Vacuum Insulation Panels (VIPs) with four core materials: fumed silica (FS) and three FS-based composites incorporating tree-based natural fibre (TNF) waste and tree-based natural ash (TNA), using a typical car painting booth (CPB) as a case study. A cradle-to-cradle evaluation is performed using two functional units: material transport capacity (6.2 tonnes per truck) and VIP dimensions (1 m × 1 m × 25 mm). VIPs were manufactured and their thermal conductivity measured over pressures of 0.64–1000 mbar and temperatures of 20–70 °C. Ageing effects were assessed by storing VIPs at 70 °C and 75% relative humidity for 12 months. Measured thermal conductivities were used to predict CPB energy consumption over a 10-year operational lifetime. Results show that FS–TNA VIPs (S4) reduced total cradle-to-cradle energy demand by 82,761 MJ compared with FS VIPs (S1) using Cut-off approach. However, this energy benefit did not translate into a climate advantage, as S4 exhibited a higher climate change impact of 893 kg CO2 eq, primarily due to pyrolysis-related emissions. Under the Allocation at Point of Substitution (APOS) approach, S4 reduced total energy demand by 17,216 MJ and climate change impact by 141 kg CO2 eq relative to FS, reflecting both operational energy savings and avoided biomass degradation emissions. When expressed per unit of energy saved relative to S1, S4 resulted in 55.0 kg CO2 eq per GJ under the modified Cut-off scenario used as the main modelling approach in this study, and (−) 8.2 kg CO2 eq per GJ under the modified APOS scenario used as an alternative allocation approach, highlighting the scenario-dependent energy–climate trade-off. Overall, the study demonstrates that trade-offs between embodied emissions, operational energy demand, and end-of-life modelling influence VIP environmental performance and provides a transparent methodology to support material selection for high-temperature industrial applications. Description: Data availability: Data will be made available on request. Wed, 18 Feb 2026 00:00:00 GMT http://bura.brunel.ac.uk/handle/2438/32842 2026-02-18T00:00:00Z http://bura.brunel.ac.uk/handle/2438/32826 Title: Experimental Study on Ultra-Precision Turning of Freeform Optical Surfaces of Polymethyl Methacrylate with Nanometer Surface Roughness Authors: Wang, X; Bai, Q; Zhao, L; Cheng, K Abstract: The high performance of optical components is contingent upon the quality of their optical surfaces, thereby imposing elevated standards on the methodologies employed for their fabrication. This study involved experimental research on freeform optical surface elements of polymethyl methacrylate with nano-surface roughness. In this study, the effects of machining parameters of ultra-precision slow tool servo turning on the surface roughness of different types of areas of freeform optical surfaces in the finishing stage were analysed. Based on the analysis of ultra-precision turning test results for freeform optical surfaces, a novel evaluation method for surface quality is proposed to assess the overall uniformity of surface quality across the entire freeform optical surface. Building upon this proposed evaluation method for overall surface quality uniformity, the processing method of high-quality freeform optical surfaces is studied. The results show that in the finishing stage, the radial feed rate exerts the greatest influence on the surface roughness of the freeform optical surface, especially the surface roughness of the concave surface area. This will exacerbate the surface quality inhomogeneity of the freeform optical surface. Based on the analysis results, optimal machining parameters were selected for processing trials. Concurrently, additional machining tests were conducted to further validate the influence of radial feed rate. Ultimately, a nano-scale PMMA freeform optical surface with uniform overall surface quality was achieved. The variation in surface roughness in different regions of the optical freeform is regulated to stabilise within 2 nm on the surface of polymethyl methacrylate. The overall uniformity of surface quality across the entire freeform optical surface was maintained at a high level. Description: Data Availability Statement: The raw data supporting the conclusions of this article will be made available by the authors on request.; Supplementary Materials: The following supporting information can be downloaded at: https://www.mdpi.com/article/10.3390/app16031350/s1, Figure S1. Flowchart for Assessing the Concavity and Convexity Properties of Free-Form Surfaces. Thu, 29 Jan 2026 00:00:00 GMT http://bura.brunel.ac.uk/handle/2438/32826 2026-01-29T00:00:00Z