Investigació acció participativa en universitats politècniques: el cas d'utòpika a la Universitat Politècnica de València

Utòpika és una xarxa de professor(e)s i estudiants de la UPV que practica la investigació activa participativa. En col·laboració amb organitzacions no lucratives, busca resoldre problemes de la societat valenciana des d'un vessant tècnic però també ambiental i social. Utòpika compleix dos anys (2009-2011) i vol fer una parada en el camí amb aquest llibret per compartir el que s'ha fet i el que queda per fer, tot en el marc d'una reflexió sobre la necessitat de promoure universitats compromeses amb un món més just.Palau Salvador, G. (2012). Investigació acció participativa en universitats politècniques: el cas d'utòpika a la Universitat Politècnica de València. Editorial Universitat Politècnica de València. http://hdl.handle.net/10251/72475EDITORIA

Modelo numérico de cavitación para geometrías sencillas utilizando FLUENT V6.1

[EN] Cavitation is a phenomenon that can be present in several agro-forestry applications such as irrigation pressure-reducing valves, sprinkler orifices or even in the flow through xylem vessels inside plants. In the present research, numerical predictions of cavitation in a series of orifices, nozzles and venturis were compared to experimental measurements to show the possibilities and performances of the new cavitation model in the commercial Computational Fluid Dynamics (CFD) code FLUENT V6.1. A flashing study is also presented for the nozzle case. Model predictions for the orifice cases accurately capture cavitation inception and its influence on the orifice discharge coefficient. However, when an unsteady flow is modeled, the cavitation phenomenon is not simulated properly and leads to a steady situation. In general, the new cavitation model in FLUENT V6.1 provides very reliable simulation for easy geometries when steady flow is assumed.[ES] Los procesos de cavitación tienen relevancia en diferentes aspectos del área agroforestal, como en válvulas reductoras de presión para riego, chorros en aspersores e incluso en el flujo de savia en el xilema de las plantas. En este trabajo se ha validado el nuevo modelo de cavitación incluido en el programa comercial de mecánica de fluidos computacional FLUENT V6.1 en varios orificios, estrechamientos y venturis, comparando los resultados experimentales con los obtenidos por el modelo. También se presenta un estudio del fenómeno «flashing» producido en el estrechamiento. Las predicciones del modelo en el caso de los orificios muestran una buena estimación del momento de inicio de la cavitación así como de su desarrollo, estimado con el coeficiente de descarga del orificio. Sin embargo, cuando se trata de modelar el flujo en estado no estacionario, el proceso de cavitación no es simulado correctamente conduciendo a una situación estacionaria. De todo ello podemos concluir que el nuevo modelo de cavitación simula adecuadamente la cavitación en el flujo a través de geometrías sencillas, como los orificios y estrechamientos, en estado estacionario.Palau-Salvador, G.; González Altozano, P.; Arviza Valverde, J. (2007). Numerical modeling of cavitating flows for simple geometries using FLUENT V6.1. Spanish Journal of Agricultural Research. 5(4):460-469. https://doi.org/10.5424/sjar/2007054-2694604695

Critical Thinking Using Project-Based Learning: The Case of The Agroecological Market at the "Universitat Politècnica de València"

[EN] Higher education institutions play an important role in the transition processes to sustainable development through developing critical thinking (CT) in their students. The case of the Research Methodology course of the International Cooperation Master's degree at the Universitat Politecnica de Valencia is a paradigmatic case of experiential learning, where students face their own realities related to sustainable topics through an action research project with the Agroecological Market (AM). The learning methodology is project-based learning and helps the participants to deeply analyze problems related to the transition of socio-technical systems, such as sustainable food. The objective of this research was to analyze the contribution of project-based learning to students' critical thinking through a qualitative analysis of the pedagogical outputs obtained during the course. The analysis and results are structured in three dimensions of critical thinking: (i) students' critical attitude towards reality; (ii) students' ability to reason and analyze in order to form their own rigorous judgments; and (iii) students' capacity to construct and deconstruct their own experiences and meanings. The results show that project-based learning using a real-life scenario helped students reflect on their critical thinking and the challenges that our societies face for a transition to sustainability.This research was partially funded by the ADVANCED HUMAN CAPITAL FORMATION PROGRAM "ANID/DOCTORADO BECAS CHILE/2018-72190320".Aranguiz, P.; Palau-Salvador, G.; Belda, A.; Peris Peris, J. (2020). Critical Thinking Using Project-Based Learning: The Case of The Agroecological Market at the "Universitat Politècnica de València". Sustainability. 12(9):1-23. https://doi.org/10.3390/su12093553S123129Rotmans, J., Kemp, R., & van Asselt, M. (2001). More evolution than revolution: transition management in public policy. Foresight, 3(1), 15-31. doi:10.1108/14636680110803003Jorgenson, S. N., Stephens, J. C., & White, B. (2019). Environmental education in transition: A critical review of recent research on climate change and energy education. The Journal of Environmental Education, 50(3), 160-171. doi:10.1080/00958964.2019.1604478Avelino, F., & Wittmayer, J. M. (2015). Shifting Power Relations in Sustainability Transitions: A Multi-actor Perspective. Journal of Environmental Policy & Planning, 18(5), 628-649. doi:10.1080/1523908x.2015.1112259Geels, F. W. (2002). Technological transitions as evolutionary reconfiguration processes: a multi-level perspective and a case-study. Research Policy, 31(8-9), 1257-1274. doi:10.1016/s0048-7333(02)00062-8Farla, J., Markard, J., Raven, R., & Coenen, L. (2012). Sustainability transitions in the making: A closer look at actors, strategies and resources. Technological Forecasting and Social Change, 79(6), 991-998. doi:10.1016/j.techfore.2012.02.001Jenkins, K., Sovacool, B. K., & McCauley, D. (2018). Humanizing sociotechnical transitions through energy justice: An ethical framework for global transformative change. Energy Policy, 117, 66-74. doi:10.1016/j.enpol.2018.02.036Stephens, J. C. (2019). Energy Democracy: Redistributing Power to the People Through Renewable Transformation. Environment: Science and Policy for Sustainable Development, 61(2), 4-13. doi:10.1080/00139157.2019.1564212Heffron, R. J., & McCauley, D. (2018). What is the ‘Just Transition’? Geoforum, 88, 74-77. doi:10.1016/j.geoforum.2017.11.016Adlong, W. (2012). 100% Renewables as a Focus for Environmental Education. Australian Journal of Environmental Education, 28(2), 125-155. doi:10.1017/aee.2013.5Freire, P. (1976). Literacy and the possible dream. Prospects, 6(1), 68-71. doi:10.1007/bf02220134Colás-Bravo, P., Magnoler, P., & Conde-Jiménez, J. (2018). Identification of Levels of Sustainable Consciousness of Teachers in Training through an E-Portfolio. Sustainability, 10(10), 3700. doi:10.3390/su10103700González Morales, A. L. (2019). Affective Sustainability. The Creation and Transmission of Affect through an Educative Process: An Instrument for the Construction of more Sustainable Citizens. Sustainability, 11(15), 4125. doi:10.3390/su11154125Cañabate, D., Serra, T., Bubnys, R., & Colomer, J. (2019). Pre-Service Teachers’ Reflections on Cooperative Learning: Instructional Approaches and Identity Construction. Sustainability, 11(21), 5970. doi:10.3390/su11215970Straková, Z., & Cimermanová, I. (2018). Critical Thinking Development—A Necessary Step in Higher Education Transformation towards Sustainability. Sustainability, 10(10), 3366. doi:10.3390/su10103366Díaz-Iso, A., Eizaguirre, A., & García-Olalla, A. (2019). Extracurricular Activities in Higher Education and the Promotion of Reflective Learning for Sustainability. Sustainability, 11(17), 4521. doi:10.3390/su11174521Urquidi-Martín, A., Tamarit-Aznar, C., & Sánchez-García, J. (2019). Determinants of the Effectiveness of Using Renewable Resource Management-Based Simulations in the Development of Critical Thinking: An Application of the Experiential Learning Theory. Sustainability, 11(19), 5469. doi:10.3390/su11195469Vogler, J. S., Thompson, P., Davis, D. W., Mayfield, B. E., Finley, P. M., & Yasseri, D. (2017). The hard work of soft skills: augmenting the project-based learning experience with interdisciplinary teamwork. Instructional Science, 46(3), 457-488. doi:10.1007/s11251-017-9438-9HMELO-SILVER, C. E., DUNCAN, R. G., & CHINN, C. A. (2007). Scaffolding and Achievement in Problem-Based and Inquiry Learning: A Response to Kirschner, Sweller, and Clark (2006). Educational Psychologist, 42(2), 99-107. doi:10.1080/00461520701263368JENSEN, B. B. (2004). Environmental and health education viewed from an action‐oriented perspective: a case from Denmark. Journal of Curriculum Studies, 36(4), 405-425. doi:10.1080/0022027032000167235Saiz Sánchez, C., & Fernández Rivas, S. (2012). Pensamiento crítico y aprendizaje basado en problemas cotidianos. REDU. Revista de Docencia Universitaria, 10(3), 325. doi:10.4995/redu.2012.6026Ortega-Sánchez, D., & Jiménez-Eguizábal, A. (2019). Project-Based Learning through Information and Communications Technology and the Curricular Inclusion of Social Problems Relevant to the Initial Training of Infant School Teachers. Sustainability, 11(22), 6370. doi:10.3390/su11226370Occhipinti. (2019). A Problem-Based Learning Approach Enhancing Students’ Awareness of Natural Risks and Hazards in Italian Schools. Geosciences, 9(7), 283. doi:10.3390/geosciences9070283Butler, H. A. (2012). Halpern Critical Thinking Assessment Predicts Real-World Outcomes of Critical Thinking. Applied Cognitive Psychology, 26(5), 721-729. doi:10.1002/acp.2851Ennis, R. H. (2016). Critical Thinking Across the Curriculum: A Vision. Topoi, 37(1), 165-184. doi:10.1007/s11245-016-9401-4Shephard, K., & Egan, T. (2018). Higher Education for Professional and Civic Values: A Critical Review and Analysis. Sustainability, 10(12), 4442. doi:10.3390/su10124442Facione, P. A. (2000). The Disposition Toward Critical Thinking: Its Character, Measurement, and Relationship to Critical Thinking Skill. Informal Logic, 20(1). doi:10.22329/il.v20i1.2254Steed, E. A., & Shapland, D. (2019). Adapting Social Emotional Multi-Tiered Systems of Supports for Kindergarten Classrooms. Early Childhood Education Journal, 48(2), 135-146. doi:10.1007/s10643-019-00996-8Sanders, K. E., Molgaard, M., & Shigemasa, M. (2019). The relationship between culturally relevant materials, emotional climate, ethnic composition and peer play in preschools for children of color. Journal for Multicultural Education, 13(4), 338-351. doi:10.1108/jme-02-2019-0014McCusker, S. (2019). Everybody’s monkey is important: LEGO® Serious Play® as a methodology for enabling equality of voice within diverse groups. International Journal of Research & Method in Education, 43(2), 146-162. doi:10.1080/1743727x.2019.1621831Cuéllar-Padilla, M., & Ganuza-Fernandez, E. (2018). We Don’t Want to Be Officially Certified! Reasons and Implications of the Participatory Guarantee Systems. Sustainability, 10(4), 1142. doi:10.3390/su10041142Clarke, P., & Oswald, K. (2010). Introduction: Why Reflect Collectively on Capacities for Change?1. IDS Bulletin, 41(3), 1-12. doi:10.1111/j.1759-5436.2010.00132.xWalker, M., McLean, M., Dison, A., & Peppin-Vaughan, R. (2009). South African universities and human development: Towards a theorisation and operationalisation of professional capabilities for poverty reduction. International Journal of Educational Development, 29(6), 565-572. doi:10.1016/j.ijedudev.2009.03.002Woodhill, J. (2010). Capacities for Institutional Innovation: A Complexity Perspective. IDS Bulletin, 41(3), 47-59. doi:10.1111/j.1759-5436.2010.00136.xAragón, A. O. (2010). A Case for Surfacing Theories of Change for Purposeful Organisational Capacity Development. IDS Bulletin, 41(3), 36-46. doi:10.1111/j.1759-5436.2010.00135.xAdelman, C. (1993). Kurt Lewin and the Origins of Action Research. Educational Action Research, 1(1), 7-24. doi:10.1080/0965079930010102Lewin, K. (1944). A Research Approach to Leadership Problems. Journal of Educational Sociology, 17(7), 392. doi:10.2307/2262546Fals-Borda, O. (1987). The Application of Participatory Action-Research in Latin America. International Sociology, 2(4), 329-347. doi:10.1177/026858098700200401Anselma, M., Chinapaw, M., & Altenburg, T. (2020). «Not Only Adults Can Make Good Decisions, We as Children Can Do That as Well» Evaluating the Process of the Youth-Led Participatory Action Research ‘Kids in Action’. International Journal of Environmental Research and Public Health, 17(2), 625. doi:10.3390/ijerph17020625Määttä, K., Hyvärinen, S., Äärelä, T., & Uusiautti, S. (2020). Five Basic Cornerstones of Sustainability Education in the Arctic. Sustainability, 12(4), 1431. doi:10.3390/su12041431Puccio, G. J., Burnett, C., Acar, S., Yudess, J. A., Holinger, M., & Cabra, J. F. (2018). Creative Problem Solving in Small Groups: The Effects of Creativity Training on Idea Generation, Solution Creativity, and Leadership Effectiveness. The Journal of Creative Behavior, 54(2), 453-471. doi:10.1002/jocb.38

Turbulence Structures in the Flow through Emergent Vegetation

Source: ICHE Conference Archive - https://mdi-de.baw.de/icheArchiv

Influence of the secondary motions on pollutant mixing in a meandering open channel flow

[EN] This paper presents large eddy simulation of turbulent flow in a meandering open channel with smooth wall and rectangular cross-section. The Reynolds number based on the channel height is 40,000 and the aspect ratio of the cross-section is 4.48. The depthaveraged mean stream-wise velocity agree well to experimental measurements. In this specific case, two interacting cells are formed that swap from one bend to the other. Transport and mixing of a pollutant is analysed using three different positions of release, e.g. on the inner bank, on the outer bank and on the centre of the cross section. The obtained depth-average mean concentration profiles are reasonably consistent with available experimental data. The role of the secondary motions in the mixing processes is the main focus of the discussion. It is found that the mixing when the scalar is released on the centre of the cross-section is stronger and faster than the mixing of the scalar released on the sides. When the position of release is close to a bank side, the mixing is weaker and a clear concentration of scalar close to the corresponding side-wall can be observed in both cases.MGV acknowledges the financial support of the Spanish Ministry of Education through the program Jose Castillejo.Moncho Esteve, IJ.; Folke, F.; García-Villalba, M.; Palau-Salvador, G. (2017). Influence of the secondary motions on pollutant mixing in a meandering open channel flow. Environmental Fluid Mechanics. 17(4):695-714. https://doi.org/10.1007/s10652-017-9513-4S695714174Julien PY, Duan JG (2005) Numerical simulation of the inception of channel meandering. Earth Surf Process Landf J Br Geomorphol Res Group 30:1093–1110Boussinesq J (1868) Mémoire sur l’influence des frottements dans les mouvements reguliers des fluids. J Math Pures Appl 13:377–424Thomson J (1876) On the origin of windings of rivers in alluvial plains, with remarks on the flow of water round bends in pipes. 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In: Proceedings of 8th FMTM-CongressMockmore C (1943) Flow around bends in stable channels. Trans ASCE 3:334Blanckaert K, De Vriend HJ (2004) Secondary flow in sharp open-channel bends. J Fluid Mech 498:353–380. doi: 10.1017/S0022112003006979Balen WV, Uijttewaal WSJ, Blanckaert K (2009) Large-eddy simulation of a mildly curved open-channel flow. J Fluid Mech 630:413–442. doi: 10.1017/S0022112009007277van Balen W, Blanckaert K, Uijttewaal WSJ (2010) Analysis of the role of turbulence in curved open-channel flow at different water depths by means of experiments, LES and RANS. J Turbul 11:N12. doi: 10.1080/14685241003789404Christensen HB (1999) Secondary turbulent flow in an infinte bend. Iahr Symp. River Coast. Estuar. MorphodynamicsBlanckaert K, Graf WH (2004) Momentum transport in sharp open-channel bends. J Hydraul Eng 130:186–198. doi: 10.1061/(ASCE)0733-9429(2004)130:3(186)Stoesser T, Ruether N, Olsen NRB (2010) Calculation of primary and secondary flow and boundary shear stresses in a meandering channel. Adv Water Resour 33:158–170. doi: 10.1016/j.advwatres.2009.11.001Blanckaert K, Duarte A, Chen Q, Schleiss AJ (2012) Flow processes near smooth and rough (concave) outer banks in curved open channels. J Geophys Res Earth Surf 117:F04020. doi: 10.1029/2012JF002414Vaghefi M, Akbari M, Fiouz AR (2016) An experimental study of mean and turbulent flow in a 180 degree sharp open channel bend: secondary flow and bed shear stress. KSCE J Civ Eng 20:1582–1593. doi: 10.1007/s12205-015-1560-0Kang S, Lightbody A, Hill C, Sotiropoulos F (2011) High-resolution numerical simulation of turbulence in natural waterways. 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Greening the post crisis. Collectivity in private and public community gardens in València (Spain)

[EN] Unlike other Western European countries, community gardens have appeared very recently in Spain, and they have rapidly increased during the last decade. Community gardens have adopted different forms -rental, municipal and associative- with contrasted managerial practices. This paper analyzes collectivity of community gardens in Valencia (Spain), including private initiatives, through semi-structured interviews conducted in different gardens of the Valencia Metropolitan Area. Results show how the financial crisis has acted as a catalyst for urban greening latent demands, causing the expansion of community gardens. Despite the different structure, practices and rules of private and public gardens, all of them share aims and actions related to urban greening, food sovereignty, organic farming and community building, and show similar benefits to those observed in other countries. Moreover, the rental gardens allow farmers to expand their services and to engage directly with consumers.Palau-Salvador, G.; De Luis, A.; Juan Pérez, J.; Sanchis Ibor, C. (2019). Greening the post crisis. Collectivity in private and public community gardens in València (Spain). Cities. 92:292-302. https://doi.org/10.1016/j.cities.2019.04.005S2923029

Simple inlet devices and their influence on thermal stratification in a hot water storage tank

[EN] Thermal energy storage is a technology used mostly in buildings and industries in order to preserve thermal energy so that the stored energy can be used at a later time. Thermal stratification during the charge process in a cylindrical water tank was investigated using tools of Computational Fluid Dynamics (CFD). Simulations were validated by means of experimental measurements of time-dependent temperature profiles. The results showed that the model was able to adequately capture the experimental temperature evolution in the tank for all the validation cases. Once validated the model, simple modifications of the usual inlet devices and inflow rate by CFD techniques were accomplished with the intention of improving the tank performance. It was found that the modifications of the simulated inlet devices affected the stratification level. This could lead to improve designs and optimize system efficiency. The analyses confirmed numerically the results obtained experimentally, and it was evidenced that a sintered bronze conical diffuser can improve stratification compared to a conventional bronze elbow inlet. Therefore, CFD techniques proved to be quite a valuable complement of experimental studies. The use of low inflow, smooth out inlet velocity and operate inflow upwards near the top of the tank enhanced stratification. (C) 2017 Published by Elsevier B.V.This research was supported by the Plan Nacional de I+D+i del Ministerio de Ciencia e Innovacion (ENE2009-13376). The authors would like to thank L.H. Sanchis for his valuable and constructive suggestions during the planning and development of this research.Moncho Esteve, IJ.; Gasque Albalate, M.; González Altozano, P.; Palau-Salvador, G. (2017). Simple inlet devices and their influence on thermal stratification in a hot water storage tank. Energy and Buildings. 150:625-638. https://doi.org/10.1016/j.enbuild.2017.06.012S62563815