Valentina Stojceska

Brunel University of London

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S.A. Tassou

Brunel University of London

Hadi Tannous

Brunel University of London

Kemal Masera

Brunel University of London

Maria Kolokotroni

Brunel University of London

Lisa Gobio-Thomas

Brunel University of London

Mohamed Darwish

Brunel University of London

Lisa Baindu Gobio-Thomas

Brunel University of London

I. Alaunyte

Manchester Metropolitan University

P.A. Kew

Heriot-Watt University

Bernardo Buonomo

University of Campania "Luigi Vanvitelli"

Cooperative Institutions

Brunel University of London

Centre for Sustainable Energy

University of Naples Federico II

University of Minho

Universidade do Porto

University of New England

Universidade de Vigo

Université Clermont Auvergne

National Botanical Research Institute

Imperial College London

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Numerical Analysis of a Solar-Powered Tube Heater

Proceedings of the World Congress on Mechanical, Chemical, and Material Engineering (2023)

Hadi Tannous Valentina Stojceska S.A. Tassou

This paper evaluates the performance of a solar-powered tube heater that uses air impingement jets to heat steel tubes in the powder-based coating process.To evaluate the thermal performance of the tube heater, two numerical models, ANSYS FLUENT Dynamic Mesh (FDM) and ANSYS FLUENT Transient Thermal (FTT), were developed and their accuracy and computational efficiency were compared.The FDM model analyzed the heat transfer in the tube heater by simulating a moving steel tube with a steady heat source while the FTT model by simulating a steady steel tube with a moving heat source.Results showed the FDM model to be computationally more time and cost-efficient, requiring 4 processors and 4 days to run compared to the FTT model which required 40 processors and 31 days.On the other hand, the FDM model showed a more detailed temperature contour of the tube with higher temperatures on the edges due to air crossflow.However, this did not have any significant effect on the final average temperature of the tube which was found to reach 76 o C by both models, consequently reducing the required load of the induction heater by 22% and the Greenhouse gas (GHG) emissions of the induction heater by 2.15 gCO2e/m.

Solar powered

10.11159/htff23.224

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Citations (2)

Contributors

Elsevier eBooks (2022)

Dominic Agyei C. Anandharamakrishnan Federico Antonioli Jeetendra Prakash Aryal Thierry Astruc

10.1016/b978-0-323-91001-9.09990-4

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An investigation of the recent advances of the integration of solar thermal energy systems to the dairy processes

Renewable and Sustainable Energy Reviews (2022)

Kemal Masera Hadi Tannous Valentina Stojceska S.A. Tassou

The dairy industry uses a number of energy intensive thermal processes like cooling, heating and cleaning that require thermal and electrical energy. Those processes use temperatures between 4 °C and 200 °C that could be potentially powered using solar thermal energy but one of the main challenges is the complexity of selection and integration of the components used for the solar system such as solar collectors, solar heating and cooling equipment. The heating processes with the temperature requirements between 300 °C and 400 °C are mainly powered using solar parabolic trough collectors and linear Fresnel reflectors while cooling processes with solar absorption chillers. The excesses of energy of above 200 °C could be stored in a thermal energy storage system. This study critically evaluates the thermal demands of the dairy processes, reviews their existing solar thermal applications and recommends a concept design for solar thermal energy integration based on the available data. The concept design includes connection of the solar collectors and thermal energy storage to the thermal energy supply line through the absorption chiller and steam drum. The benefits comprise flexibility of the heat transfer fluid selection, independency of solar energy production to conventional production and no further modification of the conventional production system or additional capacity to support the future upgrades are required.

Chiller

Absorption refrigerator

Parabolic trough

Thermal energy

10.1016/j.rser.2022.113028

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Citations (39)

Social sustainability assessments of industrial level solar energy: A systematic review

Renewable and Sustainable Energy Reviews (2023)

Imaad Zafar Valentina Stojceska S.A. Tassou

This study discusses the application of Social Life Cycle Assessment on existing Solar Thermal Energy and similar energy systems used in industrial supply chains. Practitioners assessing STE supply chains using the current assessment framework appraised social issues such as fair payment and employee health and safety by collecting quantitative data on employee salary and social risk. Qualitative assessment methods were also deployed through community questionnaires to measure social acceptance and audits to evaluate health and safety policy compliance. The resulting data was processed using Type 1 protocol, a model which measures social performance to assess the magnitude of a company's social impact on its stakeholders. This parameter was found to take regional and universal social standards as neutral criteria to grade the level of policy compliance, regarding fairness of employee pay and client relationships. Qualitative feedback from social audits and interview dialogue was also compared to these standards, to determine the level of a company's compliance with social policy. Our literature review revealed that current practitioners provided limited elaborative commentary on an organisation's social performance within a given case study, limiting managerial insight into observed gaps in social performance. This was found to be rooted in the lack of comprehensive and empirically driven methodology adopted by most practitioners. Our research aims to develop a framework that will provide more critical insight for managerial decision-making in order to improve the social sustainability of newly developed STE and related renewable energy systems.

Salary

10.1016/j.rser.2023.113962

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Citations (12)

Electro-osmosis dewatering as an energy efficient technique for drying food materials

Energy Procedia (2019)

Abhay Menon Tonderai Reuben Mashyamombe Erdogan Kaygen Mina Sadat Mortazavi Nasiri Valentina Stojceska

In recent times, there has been a rise in interest on the applications of electro-technology based food processing methods. With drying in food industries being an energy intensive process with huge environmental impacts, the objective of this study was to design and develop a purpose-built laboratory system, for experimentally characterising an energy efficient electro-osmosis dewatering system. Electro-osmosis is a unique dewatering technique in which, moisture in food materials are removed by the application of low electric field (5-30 V). Different food materials namely, yogurt, orange pulp and egg whites were tested using electro-osmosis at 15 V and 30 V over 15 min and 30 min, respectively. The energy consumption (kWh), carbon footprint (kgCO2e) and cost indices (£/kg dried food) were also evaluated and compared with thermal drying.

Dewatering

Carbon Footprint

Osmosis

10.1016/j.egypro.2019.02.069

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The Use of Solar Thermal Heating in SPIRE and Non-SPIRE Industrial Processes

Sustainability (2023)

Hadi Tannous Valentina Stojceska Savas Tassou

This paper investigates the use of solar thermal energy systems in SPIRE (sustainable process industry through resource and energy efficiency) and non-SPIRE industries and evaluates the use a novel solar Fresnel collector for generating temperatures of up to 400 °C. The investigation showed that solar thermal energy systems were mostly integrated into the non-SPIRE industries like food and beverages, paper and pulp and the textile industries with temperature requirements of up to 150 °C while few of them were used in the SPIRE industries like the non-metallic minerals, chemicals, basic metals and water industries with temperature requirements of up to 1500 °C. The limitation of those solar energy systems was seen in their application in higher irradiance regions due to the limited operation temperature of certain types of solar collectors, which particularly affected the SPIRE industry sector. To increase their use in high and low irradiance regions, a novel solar thermal system developed by the EU-ASTEP project that could achieve a temperature of up to 400 °C was introduced. The calculations of the theoretical and technical potential application of the ASTEP system in EU industrial processes showed an increase of 43%, of which 802.6 TWh totalled the theoretical potential and 96.3 TWh the technical potential. This resulted in a reduction of greenhouse gas (GHG) emissions by 24 thousand kt CO2 equivalent, which could help industries to achieve their 2050 targets for net-zero GHG emissions.

Spire (mollusc)

10.3390/su15107807

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Citations (8)

Cereal-based dietary iron intervention for improvement of iron status in female runners

Proceedings of The Nutrition Society (2015)

I. Alaunyte Valentina Stojceska Andrew Plunkett Emma Derbyshire

An abstract is not available for this content. As you have access to this content, full HTML content is provided on this page. A PDF of this content is also available in through the 'Save PDF' action button.

Dietary iron

10.1017/s0029665115000816

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Design, numerical optimisation and experimental validation of an innovative solar-powered tube heater with multiple air impingement jets

Thermal Science and Engineering Progress (2024)

Hadi Tannous Valentina Stojceska J. M. Tavares S.A. Tassou

Solar powered

10.1016/j.tsep.2024.102990

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An environmental evaluation of food supply chain using life cycle assessment: A case study on gluten free biscuit products

Journal of Cleaner Production (2017)

López Isabel Noya V. Vasilaki Valentina Stojceska Sara González‐García Chantelle Kleynhans

This paper assesses the environmental profile of the biscuit supply chain for producing high quality gluten-free biscuits. Three different types of biscuits were considered. The assessment followed a cradle-to-grave approach applying the ISO standards in compliance with the Product Category Rules (PCR) defined within EPD (Environmental Product Declaration) for bakery products. Analogous environmental profiles were implemented for assessing the products: It was found that the main hotspot in all impact categories was ingredients production with the range contribution from 22.2% to 84.9%, followed by transportation. Initial hypotheses for ingredients origin and waste management practices were demonstrated to have a key influence on the environmental results: higher packaging recycling rates and local ingredients usage led to improved environmental results (up to 5.5%) while direct food waste disposal was responsible for slightly unfavourable performance relative to base case (below 1%). Additionally, healthier ingredients such as xylitol and fructose were used to evaluate their potential benefits from an environmental perspective. It was found that only the use of fructose was a suitable alternative sweetener for more sustainable production.

Food Waste

Gluten free

10.1016/j.jclepro.2017.08.226

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Citations (52)

Design, Numerical Optimisation and Experimental Validation of an Innovative Solar-Powered Tube Heater with Multiple Air Impingement Jets

Valentina Stojceska

This research investigates a novel tube heater designed for the seamless integration of an innovative solar thermal system into the powder-based coating process of steel tubes. It incorporates a comprehensive numerical model developed and assessed using ANSYS FLUENT, concentrating on seven critical parameters that significantly influence the tube heater's performance and size. These parameters include tube heater length, jets’ length, funnel height, Z/Djet, Y/Djet and X/Djet ratios, as well as jet diameter. The findings underline the critical role of tube heater length in enhancing heat transfer and maximising thermal efficiency, while reducing jet length and funnel height demonstrated negligible effects on thermal performance, promoting material economy. A lower Z/Djet ratio enhanced heat transfer uniformity, improving thermal performance, while optimal X/Djet and Y/Djet ratios were identified as 4, maintaining a balance between heat transfer rate and energy consumption. A smaller jet diameter proved beneficial since the potential core was not achieved, increasing heat transfer to the steel tubes. The experimental model, conducted to validate the novel tube heater's performance, remarkably aligns with the numerical model, showing an R-squared value of 0.992. These results affirm the numerical setup's accuracy and reliability in capturing the tube heater's thermal behaviour. It is concluded that the novel tube heater stands as a highly efficient solution for the seamless integration of solar thermal systems into the powder-based coating process of steel tubes, promising significant emissions reduction.

Solar powered

10.2139/ssrn.4718468

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