ES - Relatórios técnicos
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Browsing ES - Relatórios técnicos by Author "Azevedo, Pedro"
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- Development of advanced characterisation tools for the prediction of reburn performance in PF combustors: 3rd annual reportPublication . Carapau, Nuno; Bent, Raquel; Azevedo, Pedro; Gulyurtlu, Ibrahim; Boavida, Dulce
- NewSOL Project : Fluent: Case 0Publication . Azevedo, PedroABSTRACT: This document presents all the described steps in order to set up what is called Case 0. In the following work the inlet mass flow and temperature, the heat losses through walls, the materials themselves and their properties, including, porosity and the turbulence and radiative heat transfer models can also be changed. Everything can change, but the mesh. The only exception to this is to refine the mesh a little bit in particular areas in order to increase detail and mitigate some flow problems and improving the results.
- NewSOL Project : Thermal propertiesPublication . Azevedo, PedroABSTRACT: In order to implement the simulation of as thermal process in a computational fluid dynamics application, it is needed to know the thermal properties of the involved chemical species., namely the density, the specific heat, the dynamic viscosity and the thermal conductivity. The experimental determination of the thermal properties for the molten salts and for the S. Domingos Mines ore were performed by, respectively, Yara and UEvora. In Section 2, the determined thermal properties for both materials are presented; In Section 3, the thermal properties for the molten salts are assessed and adapted to the CFD application package; In Section 4, the same work is performed for the ore slurry; and in Section 5 some conclusions are disclosed.
- NewSOL Project: Available CFD models assessmentPublication . Lima, Maria Margarida de Lemos Canedo Giestas; Azevedo, PedroABSTRACT: The partial differential equations that govern fluid flow and heat transfer are not usually amenable to analytical solutions, except for very simple cases. Therefore, in order to analyze fluid flows, flow domains are split into smaller subdomains (made up of geometric primitives like hexahedron and tetrahedron in 3D and quadrilaterals and triangles in 2D). The governing equations are then discretized and solved inside each of these subdomains. In the present situation, a finite volume method will be used to solve the approximate representation of the equations’ system. Care must be taken to ensure proper continuity of solution across the common interfaces between two subdomains, so that the approximate solutions inside various portions can be put together to give a complete picture of fluid flow in the entire domain. The subdomains are often called elements or cells and the collection of all elements or cells is called a mesh or grid. The origin of the term mesh (or grid) goes back to early days of CFD when most analyses were 2D in nature. For 2D analyses, a domain split into elements resembles a wire mesh, hence the name.
- NewSOL Project: Implementation and validation tests for Fluent : Case 0Publication . Seram, Victor; Lima, Maria Margarida de Lemos Canedo Giestas; Azevedo, PedroABSTRACT: The present report was made according to the implementation of “Fluent: Case 0”1 of the NewSol Project (Grant nº 720985). The Ansys computational package software was used for the conducted simulations. A 2D geometry symmetrical at the middle axis was constructed. Several meshes were both made and simulated for the minimum computational cost. For simplicity of the problem and at this early stage of development of the model, the ullage space was taken to be filled with HTF (Heat Transfer Fluid). Although HTF fills the ullage space in the tank, this is not in good agreement with the condition described in Case 0 which considers air as the medium. All the simulations were performed with steady state conditions. However, in the future transient state would be used.
- NewSOL Project: Thermal calculations for TES tank predesign : EMSP case-studyPublication . Azevedo, PedroABSTRACT: LNEG is one of the partners involved in Task 2.2 “Predesign of tank and module system architectures”. The present document reports work developed by LNEG for partial fulfillment of deliverable D2.1 “Preliminary selection of materials compositions and TES system predesign”. Preliminary data were already published in Azevedo (2017) and on D2.1 “Preliminary selection of materials compositions and TES system predesign”. The present document presents the efficiency approach and the methodology for heat losses and temperature inside the walls calculations. Additionally, the EMSP is hereby described as a case-study and its dimensions, materials, and the aforementioned heat losses and temperature inside the walls, were estimated.
- NewSOL Project: Thermocline degradationPublication . Azevedo, PedroABSTRACT: According to Task 6.3 of DOA, LNEG was supposed “to define an appropriate monitoring scheme and set of tests to collect the experimental data from the thermocline tank (TCT), necessary to the evaluation of the thermodynamic performance of the prototype and improvement and validation of the computational models”. However, due to known delays on the construction phase of the thermocline tank, the experimental period and its related data is not available, at the moment. Nevertheless, although the validation of the computational models was not possible, some additional adaptions to the models and analysis were developed that can impact namely the assessment of the cycling effect over effective thermal capacity, including for an upscaled solution. This report approaches the problem of the thermocline tank (TCT) degradation that can develop after consecutive cycles. Besides the control strategy, calculations were performed towards the assessment of the prototype TCT performance considering the control scheme disclosed in D7.91 and in some literature2. An alternate operation strategy is proposed, and its performance assessed and, finally, an upscaled TCT, also disclosed in D7.9, is also assessed considering the alternate operation strategy.
- Solar Tower Testing Facility (STTF-100)Publication . Azevedo, Pedro; Cardoso, João P.ABSTRACT: The Concentrated Solar Power (CSP) research field denotes a high degree of multidisciplinarity, gathering several competences with regard to both exact sciences and engineering, such as optics, mechanics, thermodynamics, materials, chemistry, computation, control, instrumentation and so on.
- STTF 100 : Memória descritiva : energia e comunicaçõesPublication . Azevedo, PedroABSTRACT: A Solar Tower Testing Facility – 100 (STTF-100) é uma infra-estrutura experimental que consiste num concentrador solar do tipo sistema de receptor central, também designado por torre solar, e que ocupa uma área total de aproximadamente 725 m2. Esta instalação encontra-se localizada no campus do LNEG em Lisboa.