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Highlights • Creativity is a key competence in engineering degrees. • Team working and individual skills are key for developing innovative projects. • Logical framework of a project identify different roles needed in each step. • Investor's Exercise foster creativity, team working, attitude towards work and communication skills. Abstract In the process of designing and solving problems related to engineering, the ability to find innovative solutions is becoming more and more relevant. Following this principle, engineers should acquire transversal competences through courses such as Project Evaluation and Risk Management , in which they learn to solve current problems through innovation. The project evaluation supposes an approach to the real world, since an idea is evaluated in the different phases of the logical cycle of a project, culminating with its techno-economic analysis and investment. Following the analogy, engineers develop and evaluate their ideas and present them to a group of professors and professionals posing as investors. The results present a holistic approach to the evaluation of ideas and the capacity of a team to develop engineering projects. The study performs an assessment methodology for an open-innovation concept, and the investor's exercise may contribute to practical strategies to foster creative engineers. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents a new mathematical model developed to reproduce the performance of a generic sludge digester working either under aerobic or anaerobic operational conditions. The digester has been modelled as two completely mixed tanks associated with gaseous and liquid volumes. The conversion model has been developed based on a plant wide modelling methodology (PWM) and comprises biochemical transformations, physicochemical reactions and thermodynamic considerations. The model predicts the reactor temperature and the temporary evolution of an extensive vector of model components which are completely defined in terms of elemental mass fractions (C, H, O, N and P) and charge density. Thus, the comprehensive definition of the model components guarantees the continuity of elemental mass and charge in all the model transformations and between any two systems defined by the model. The aim of the generic digester model is to overcome the problems that arise when trying to connect aerobic and anaerobic digestion processes working in series or to connect water and sludge lines in a WWTP. The modelling methodology used has allowed the systematic construction of the biochemical model which acts as an initial illustrative example of an application that has been experimentally verified. The variation of the temperature is also predicted based on a thermal dynamic model. Real data from four different facilities and a straightforward calibration have been used to successfully verify the model predictions in the cases of mesophilic and thermophilic anaerobic digestion as well as autothermal thermophilic aerobic digestion (ATAD). The large amount of data from the full scale ATAD and the anaerobic digestion pilot plants, all of them working under different conditions, has allowed the validation of the model for that case study. [Copyright &y& Elsevier]

This paper presents a new plant-wide modelling methodology for describing the dynamic behaviour of water and sludge lines in WWTPs. The methodology is based on selecting the set of process transformations needed for each specific WWTP to model all unit-process elements in the entire plant. This “transformation-based” approach, in comparison with the conventional “process-based” approach, does not require the development of specific transformers to interface the resulting unit-process models, facilitates the mass and charge continuity throughout the whole plant and is flexible enough to construct models tailored for each plant under study. As an illustrative example, a plant-wide model for a WWTP that includes carbon removal and anaerobic digestion has been constructed, and the main advantages of the proposed methodology for integrated modelling have been demonstrated. As a final consequence, this paper proposes a rewriting of the existing unit-process models according to the new standard transformation-based approach for integrated modelling purposes. [Copyright &y& Elsevier]

This paper presents a new mathematical model for Autothermal Thermophilic Aerobic Digesters. The reactor has been modelled as two completely mixed volumes to separately predict the behaviour of the liquid and gaseous phases as well as the interrelation between them. The model includes biochemical transformations based on the standard Activated Sludge Models of IWA, as well as physico-chemical transformations associated with the chemical equilibria and the mass transfer between the liquid and the gaseous phases similar to those proposed in the ADM1 of IWA. An energy balance has also been included in the model in order to predict the temperature of the system. This thermal balance takes into account all those biochemical and physico-chemical transformations that entail the most relevant heat interchanges. Reactor performance has been explored by simulation in two different scenarios: in the first where it acts as the initial stage in a Dual system, and in the second where it acts as a single-stage treatment. Each scenario enabled the identification of the relevance of the different parameters. [Copyright &y& Elsevier]

The injection of green hydrogen into the natural gas grid is a way to decarbonize the gas sector and build an economic transport route for the large-scale delivery of hydrogen. The suitability of the natural gas infrastructure for this purpose depends on the impact that hydrogen may have on the correct operation of its components and understanding the new flow conditions in the system is essential for this aim. Computational studies can anticipate the expected environment in the pipe system, assessing the readiness of the system. However, the experience on this topic is not extensive enough and deeper understanding is necessary. Here we show a CFD study to simulate the transport of H 2 /NG blends in a gas setup with the main characteristics of injection sites and gas pipelines representatives of the transmission gas network. This setup considers a blending station, the pumping and injection procedure, and different pipelines geometries to predict the behavior of various mixtures of H 2 /NG. It can be seen how (1) a good mixing is achieved in the blending station after a pipe length equivalent to 20–30 diameters is reached; (2) pumping gas by a piston type compressor shows pulsations in the flow regardless the composition of the blend that can be damped implementing mitigation measurements; and (3) asymmetries in the flow are found when the direction of the fluid changes after section reduction, but 20 diameters downstream of the reduction the flow is fully developed. [Display omitted] • Modelling the injection of hydrogen in the natural gas transmission grid. • CFD studies to anticipate the behavior of the new fluid. • Mixing quality and possible segregation in blending stations considered. • Flow pattern when DN 80 pipes expands to a DN 150 or a DN 250 pipes. • Simulation of pumping of H 2 and CH 4 by a piston type compressor. [ABSTRACT FROM AUTHOR]

Abstract: Pulmonary artery dissection is a rare clinical entity, which has been related to pulmonary arterial hypertension. It is frequently presented as cardiogenic shock or sudden death, so diagnosis is often made at autopsy. The management with best results is surgery. We report a case of pulmonary artery dissection associated with previous aortic valve replacement with a favourable outcome, using conservative medical therapy. [Copyright &y& Elsevier]