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U završnom radu opisana je osnova fotonaponskog sustava. Prikazano je koji se sustavi primjenjuju, kao i njihovi pojedini dijelovi koji su potrebni da bi sustav bio funkcionalan. Detaljno su prikazane karakteristike i sheme sustava. Posebno su opisani izmjenjivači i regulatori. U radu je opisan fotonaponski sustav za obiteljsku kuću koji pokriva vlastitu potrošnju., The final paper describes the basis of the photovoltaic system. It shows which systems are used, and their individual parts that are necessary for the system to be functional. The characteristics and schemes of the system are presented in detail. Exchangers and regulators are specially described. The paper describes a photovoltaic system for a family home that covers its own consumption.

Initiating with the conceptualization of who are Virtual Asset Service Providers (hence forward: exchangers), especially the ones who work with virtual exchangeable assets, this paper aims to study the high risk their activities suppose on increasing money laundering and what are Spain’s legal framework on money laundering and if they can be enforced on exchangers, based not only on the national legislation but also on the European Union’s existing directives on the subject. Moreover, it will be analysed the role of compliance as a practical procedure tool to prevent money laundering in exchangers activities and how the current legislation in Spain already promotes that, as the current criminal law extinguishes responsibility of legal persons who demonstrate an effective compliance program if they fulfil all requisites. Hence, this paper will be able to make a comprehensive study on exchangers, who they are and what are their activities as regulated in Spain’s legal framework. Therefore, is going to answer the investigation’s main question regarding the role of compliance to deter money laundering in this focus group. Resumen A partir de la conceptualización de los Proveedores de Servicios de Activos Virtuales (en adelante: exchangers), especialmente de aquellos que trabajan con activos virtuales intercambiables, este trabajo pretende estudiar el alto riesgo que sus actividades suponen en el incremento del blanqueo de capitales, cuál es el marco legal español sobre el blanqueo de capitales y si éste se puede aplicar a los exchangers. Para ello, la investigación se ha basado no sólo en la legislación nacional sino también en las directivas de la Unión Europea existentes en la materia. Además, se analizará el papel del compliance (o cumplimiento normativo) como herramienta de procedimiento práctico para prevenir el blanqueo de capitales en las actividades de los exchangers destacando los mecanismos mediante los cuales la legislación actual en España ya lo promueve, puesto que el derecho penal vigente extingue la responsabilidad de las personas jurídicas que demuestren un programa de compliance efectivo si cumplen todos los requisitos impuestos por ley. De este modo, este trabajo pretende realizar un estudio exhaustivo sobre los exchangers, determinando quiénes son y cuáles son sus actividades reguladas en el marco legal español. En resumen, intentará responder a la pregunta principal de la investigación sobre el papel del compliance para prevenir el blanqueo de capitales en este sector.

Initiating with the conceptualization of who are Virtual Asset Service Providers (hence forward: exchangers) , especially the ones who work with virtual exchangeable assets, this paper aims to study the high risk their activities suppose on increasing money laundering and what are Spain ’s legal framework on money laundering and if they can be enforced on exchangers, based not only on the national legislation but also on the European Union’s existing directives on the subject. Moreover, it will be analysed the role of compliance as a practical procedure tool to prevent money laundering in exchangers activities and how the current legislation in Spain already promotes that, as the current criminal law extinguishes responsibility of legal persons who demonstrate an effective compliance program if they fulfil all requisites. Hence, this paper will be able to make a comprehensive study on exchangers, who they are and what are their activities as regulated in Spain’s legal framework. Therefore, is going to answer the investigation’s main question regarding the role of compliance to deter money laundering in this focus group., A partir de la conceptualización de los Proveedores de Servicios de Activos Virtuales (en adelante: exchangers), especialmente de aquellos que trabajan con activos virtuales intercambiables, este trabajo pretende estudiar el alto riesgo que sus actividades suponen en el incremento del blanqueo de capitales, cuál es el marco legal español sobre el blanqueo de capitales y si éste se puede aplicar a los exchangers. Para ello, la investigación se ha basado no sólo en la legislación nacional sino también en las directivas de la Unión Europea existentes en la materia. Además, se analizará el papel del compliance (o cumplimiento normativo) como herramienta de procedimiento práctico para prevenir el blanqueo de capitales en las actividades de los exchangers destacando los mecanismos mediante los cuales la legislación actual en España ya lo promueve, puesto que el derecho penal vigente extingue la responsabilidad de las personas jurídicas que demuestren un programa de compliance efectivo si cumplen todos los requisitos impuestos por ley. De este modo, este trabajo pretende realizar un estudio exhaustivo sobre los exchangers, determinando quiénes son y cuáles son sus actividades reguladas en el marco legal español. En resumen, intentará responder a la pregunta principal de la investigación sobre el papel del compliance para prevenir el blanqueo de capitales en este sector.

Shallow ground-source heat pumps (GSHPs) are a promising technology for contributing to the decarbonisation of the energy sector. In heating-dominated climates, the combined use of GSHPs for both heating and cooling increases their technical potential, defined as the maximum energy that can be exchanged with the ground, as the re-injection of excess heat from space cooling leads to a seasonal regeneration of the ground. This paper proposes a new approach to quantify the technical potential of GSHPs, accounting for effects of seasonal regeneration, and to estimate the useful energy to supply building energy demands at regional scale. The useful energy is obtained for direct heat exchange and for district heating and cooling (DHC) under several scenarios for climate change and market penetration levels of cooling systems. The case study in western Switzerland suggests that seasonal regeneration allows for annual maximum heat extraction densities above 300 kWh/m$^2$ at heat injection densities above 330 kWh/m$^2$. Results also show that GSHPs may cover up to 55% of heating demand while covering 57% of service-sector cooling demand for individual GSHPs in 2050, which increases to around 85% with DHC. The regional-scale results may serve to inform decision making on strategic areas for installing GSHPs., Walch and Li contributed equally. Revision submitted to Energy

The search for technological solutions aimed at minimizing the size of a device, known as intensification, is a classic objective of process engineering. In this thesis, the intensification possibilities offered by helical tubes are studied, both for heat and mass exchangers. The use of helical tubes instead of straight tubes is indeed of interest both in terms of increasing the exchange surface per unit volume between the two fluids circulating in the exchanger and by the possibility of increasing the transfers by generating Dean vortices in the tubes. A set of CFD (Computational Fluid Dynamics) type simulations was carried out and compared with experimental results. In the end, on the basis of a systematic approach using correlations, a volume reduction of a factor of 8 was obtained, both for heat exchangers and for membrane contactors.; La recherche de solutions technologiques visant à minimiser la taille d’un dispositif, qualifiée d’intensification, est un objectif classique du génie des procédés. Dans ce mémoire, les possibilités d’intensification offertes par des tubes hélicoïdaux sont étudiées, à la fois pour des échangeurs de chaleur et de matière. L’utilisation de tubes hélicoïdaux en lieu et place de tubes droits présente en effet un intérêt à la fois en termes d’augmentation de la surface d’échange par unité de volume entre les deux fluides circulant dans l’échangeur et par la possibilité d’augmentation des transferts par génération de vortex de Dean dans les tubes. Un ensemble de simulations de mécanique des fluides numérique a été réalisé et confronté à des résultats expérimentaux. Au final, sur la base d’une démarche systématique faisant appel à des corrélations, une réduction volumique d’un facteur 8 est obtenue, tant pour les échangeurs de chaleur que pour les contacteurs à membranes.

To rapidly produce oil, downhole heating technology requires an electric heater, which is limited by the diameter of the heat injection well, with long-term working stability and high-efficiency heat transfer. Simulations indicated that heater with continuous helical baffles is more suitable for downhole heating technology than heater with segmental baffles in terms of long-term working stability. Then, experiments were conducted on four continuous helical schemes with pitches of 50, 110, 160, and 210 mm. The test results showed that, in the test scope, the heater with the helical pitch of 110 mm (H110) had the best comprehensive performance, which was 2.95–3.75 times better than that of the heater with the helical pitch of 210 mm (H210). Under the same working conditions, heaters with smaller helical pitch values produce less irreversibility in the heat transfer process. In addition, the heaters with helical pitch values of 110, 160, and 210 mm were more effective at a lower Reynolds number, whereas the heater with the helical pitch of 50 mm could be used under a wide effective range of Reynolds numbers. The conclusions are benefit to setting the heating parameters of electric heater during the process of oil shale in-situ pyrolysis.

International audience; In this work, a nonintrusive device to monitor fouling of a plate heat exchanger is presented. This device is composed of a flat electrical resistance covering a thermocouple located on the external face of a tubular holding section. The tubular holding section is placed immediately after the investigated plate heat exchanger, constituting the heating zone for which fouling monitoring is required. The principle of detection consisted in following the evolution of the measured temperature with time when a fixed thermal heat flux imposed by the resistance is dissipated through the temperature sensor. The measured temperature is supposed to vary with time since the inner temperature on the inner surface of the holding tubular zone is linked to the fouling growth. It is shown that the device response is highly correlated to the fouling occurring in the plate heat exchanger and could be a promising way for monitoring fouling rate (cheap and easy to implement avoiding cleanability drawbacks).

The search for technological solutions aimed at minimizing the size of a device, known as intensification, is a classic objective of process engineering. In this thesis, the intensification possibilities offered by helical tubes are studied, both for heat and mass exchangers. The use of helical tubes instead of straight tubes is indeed of interest both in terms of increasing the exchange surface per unit volume between the two fluids circulating in the exchanger and by the possibility of increasing the transfers by generating Dean vortices in the tubes. A set of CFD (Computational Fluid Dynamics) type simulations was carried out and compared with experimental results. In the end, on the basis of a systematic approach using correlations, a volume reduction of a factor of 8 was obtained, both for heat exchangers and for membrane contactors., La recherche de solutions technologiques visant à minimiser la taille d’un dispositif, qualifiée d’intensification, est un objectif classique du génie des procédés. Dans ce mémoire, les possibilités d’intensification offertes par des tubes hélicoïdaux sont étudiées, à la fois pour des échangeurs de chaleur et de matière. L’utilisation de tubes hélicoïdaux en lieu et place de tubes droits présente en effet un intérêt à la fois en termes d’augmentation de la surface d’échange par unité de volume entre les deux fluides circulant dans l’échangeur et par la possibilité d’augmentation des transferts par génération de vortex de Dean dans les tubes. Un ensemble de simulations de mécanique des fluides numérique a été réalisé et confronté à des résultats expérimentaux. Au final, sur la base d’une démarche systématique faisant appel à des corrélations, une réduction volumique d’un facteur 8 est obtenue, tant pour les échangeurs de chaleur que pour les contacteurs à membranes.

Organic Rankine cycle (ORC) engines often operate under variable heat-source conditions, so maximising performance at both nominal and off-design operation is crucial for the wider adoption of this technology. In this work, an off-design optimisation tool is developed and used to predict the impact of varying heat-source conditions on ORC operation. Unlike previous efforts where the performance of ORC engine components is assumed fixed, here we consider explicitly the time-varying operational characteristics of these components. A bottoming ORC system is first optimised for maximum power output when recovering heat from the exhaust gases of an internal-combustion engine (ICE) running at full load. A double-pipe heat exchanger (HEX) model is used for sizing the ORC evaporator and condenser, and a piston-expander model for sizing the expander. The ICE is then run at part-load, thus varying the temperature and mass flow rate of the exhaust gases. The tool predicts the new off-design heat transfer coefficients in the heat exchangers, and the new optimum expander operating points. Results reveal that the ORC engine power output is underestimated by up to 17% when the off-design operational characteristics of these components are not considered. In particular, the piston-expander isentropic efficiency increases at off-design operation by 10–16%, due to the reduced pressure ratio and flow rate in the system, while the evaporator effectiveness improves by up to 15%, due to the higher temperature difference across the HEX and a higher proportion of heat transfer taking place in the two-phase evaporating zone. As the ICE operates further away from its nominal point, the off-design ORC engine power output reduces by a lesser extent than that of the ICE. At an ICE part-load operation of 60% (by electrical power), the optimised ORC engine with fluids such as R1233zd operates at 77% of its nominal capacity. ORC off-design performance maps are generated, for characterising and predicting system performance, which can be used, along with the optimisation tool, by ORC system designers, manufacturers and plant operators to identify optimum performance under real operating conditions.

The I.C. Engines are losing large amount of heat into environment directly. This waste heat can be reused for other purpose like TEG, Air conditioning etc. A heat exchanger is a device that is used to transfer thermal energy between two or more fluids, between a solid surface and a fluid, or between solid particulates and a fluid, at different temperatures and in thermal contact. In case of TEG there is need to have temperature uniformity on surface of heat exchanger is important. So, it is important design achieve thermal uniformity for converting the heat into other form of energy effectively. Mr. Jadhav Vishal | Mr. D. S. Patil "Experimental Analysis of Automotive Exhaust Heat Exchanger for Thermal Uniformity" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-2 | Issue-3 , April 2018, URL: https://www.ijtsrd.com/papers/ijtsrd11702.pdf

[EN] The selection of suitable correlations for calculating heat transfer coefficients and pressure drop plays a fundamental role in the use of semi-empirical models for the simulation of the performance of a heat exchanger. Therefore, a discussion about the best way for validating a condenser model and choosing the best set of correlations for both the heat transfer coefficients and pressure drop is presented. The studies were performed for both the air and refrigerant side in a round tube and plate fin condenser. A test campaign was specially designed to cover a wide range of key parameters, such as air velocity, condensation temperature, refrigerant mass flow rate, and condenser subcooling. The options for defining the boundary conditions in the model and the accuracy metrics are discussed in detail, allowing the identification of the most suitable correlations. By using this set of correlations, the prediction error is within an error band of +/- 0.4 degrees C for the condensation temperature and +/- 0.6% in terms of capacity., The work of Alessandro Pisano on this project was partially supported by the Ministry for Economy and Finance of Spain, under the Formacion de Personal Investigador (FPI) program. Financial support from the Ministry for Economy and Finance of Spain (project number DPI2011-26771-C02-01) is also gratefully acknowledged.

This study presents a fundamental investigation of the convection heat transfer phenomenon driven by airflows in underground tunnels, with reference to the development of the so-called thermal and velocity boundary layers. The purpose of the work is to expand on the knowledge of non-isothermal problems of internal flow common to applications involving pipes, pipelines and conventional tunnels, as well as to innovative applications involving so-called energy tunnels that can provide structural support and energy supply to built environments. The study is based on three-dimensional thermo-hydraulic Computational Fluid Dynamics simulations accounting for the actual fluid flow that occurs in the aforementioned environments, and addresses the investigated phenomena by considering tunnels with different (i) shapes of the cross-section, (ii) inlet airflow velocities and (iii) surface wall(s) roughness. The results of this investigation highlight a crucial influence of the previous variables on the convection heat transfer phenomenon, which is inherently related to the development of the thermal and velocity boundary layers. The work also presents novel relationships between the convection heat transfer coefficient and the average airflow velocity that may be used in the analysis and design of the addressed non-isothermal problems of internal flow.

We investigate the kinetics of first-order magnetic phase transitions by measuring and modeling the heat-flux avalanches corresponding to the irreversible motion of the phase-boundary interface separating the coexisting low- and high-temperature stable magnetic phases. By means of out-of-equilibrium thermodynamics, we encompass the damping mechanisms of the boundary motion in a phenomenological parameter ?s. By analyzing the time behavior of the heat-flux signals measured on La(Fe-Mn-Si)13-H magnetocaloric compounds through Peltier calorimetry temperature scans performed at low rates, we relate the linear rise of the individual avalanches to the intrinsic-damping parameter ?s.

Pectin based quaternary amino anion exchanger (Pc-QAE) was prepared using simple crosslinking polymerization method. This anion exchanger was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). Pc-QAE was applied for the removal of phosphate anion from the aqueous solution. The adsorption process which was pH dependent showed maximum adsorption of phosphate anions at pH 7. Pc-QAE showed good monolayer adsorption capacity for phosphate anions which demonstrated its good capability towards Langmuir isotherm model. Moreover, the adsorption was evaluated thermodynamically and the negative value of Gibbs free energy (−1.791 KJ/mol) revealed the spontaneity of adsorption process. The value of ΔH° and ΔS° were found to be 15.28 and 49.48 KJ/mol, respectively representing the endothermic nature and enhancement in degree of freedom due to the adsorption process., final draft, peerReviewed

Ovaj je završni zadatak vezan za projekt CARBEN. "Carbon footprint reduction and energy efficiency via development an advanced tehniques for Total Site integration" je projekt koji se provodi na Fakultetu strojarstva i brodogradnje u Zagrebu od 2014. godine teži postignućima koje će biti objašnjene u daljnjem tekstu. Cilj je bio povećati regeneraciju topline na tri odvojena mjesta korištenjem Total site metode i izračunati potencijal uštede energije i ekonomske pokazatelje štednje novca. Zadatak zadaje industrijski proces A, industrijski proces B i stambeno područje C. Svaki od njih ima više struja hlađenja i grijanja, kao i kondenzacije i isparavanja. Prvo, pomoću Pinch metode, izračun nas je doveo do minimalne topline grijanja i hlađenja uzimajući u obzir minimalnu temperaturnu razliku od 10° C. Također, izračunata je mreža izmjenjivača topline, kao i grafički prikaz mreže. Nakon toga primijenjena je Total site metoda na minimalnu potrebnu dovedenu i odvedenu toplinu, kao i izračun mreže izmjenjivača na Total siteu. Također je definiran medij preko kojeg se prenosi toplina unutar total sitea preko minimalnih površina potrebnih za provođenje topline. Koristeći dobivene i izračunate podatke izvedena je ekonomska analiza. Cilj je vidjeti razliku potrošnje između izračunate regeneracije topline u odnosu na procese bez ikakve regeneracije. Korišteni su podaci poput cijene izmjenjivača, diskontne stope, cijene površine izmjenjivača za izmjenu topline i koeficijent nelinearnosti između površine izmjenjivača i cijene po metru kvadratnom izmjenjivačke površine. Rezultati su pokazali regeneraciju od 4433 kW, s time da odvođenje topline izvana nije uopće potrebno, pošto su se vruće struje dovele na definiranu temperaturu isključivo regeneracijom, a vanjsko dovođenje topline potrebno je samo 1778,85 kW. Rezultirajuća ušteda unutar 5 godine ja 2.921.058,15 eura današnje vrijednosti novca u odnosu na procese bez regeneracije topline. Troškovi ugradnje izmjenjivača i trošak samih izmjenjivača iznosi 378.564 eura. Također je velika prednost postrojenja s regeneracijom topline niža emisija ugljičnog dioksida, što je od velike važnosti za današnji svijet. Težnja za manjim emisijama u svjetskoj politici je velika zbog sve većih utjecaja zagađivača na okoliš, te brojnih posljedica koje proizlaze iz toga. This BSc thesis assignment is tied to the project CARBEN. The 'Carbon footprint reduction and energy efficiency via development an advanced tehniques for Total Site integration' is a project which has been carried out on Faculty of mechanical engineering and naval architecture in Zagreb since 2014. The thesis has acomplished great benefits which will be explained in further text. The goal was to maximise the regeneration of heat on three seperate sites using Total site method and to calculate its potential of energy savings and economic indicators of saving money. The assignment has and industrial process A, industrial process B and residential and commercial area also known as process C. Each one of them has number of cooling and heating streams, as well as condensation and evaporation streams. Firstly, using basic Pinch method, the calculations led us to minimum hot and cold utility for minimum temperature difference of 10°C. Also, the calculations for heat exchanger network (HEN) were made, and all of the graphical apstract as well. Afterwards, the total site method was applied for these minimum hot and cold utilities, and the calculation of HEN inside the total site. Also, the intermediate utility was defined using minimum heat transfer area of the heat exchangers. Using all these calculations and obtained results, the economic analysis was made. The goal was to see what is the difference of costs for processes with regeneration an without it. The provided data such as installation of heat exchangers, money discount rate, cost of one squared meter of heat transfer surface and nonlinearity coefficient of price of the heat transfer surface was used. The results were astonishing, the regeneration acomplished is 4433kW for cold and hot utility, and only 1778,85kW of additional hot utility was needed and no cold utility at all because all hot streams were cooled down via regeneration. The result was 2.921.058,15 euros of present value money of savings in 5 years compared with processes without regeneration. The expenses for installation and revamp were included and they were around 378.564 euros. Also, the benefits beside capital profits are lower carbon emissions, which are of great importance in todays world.

WOS:000384779300072; International audience; This paper documents a numerical study of time-dependent melting dominated by natural convection in a cylinder filled with a phase change material. In accord with constructal design, the search is for effective heat-flow architectures. The volume-constrained improvement of the designs for heat flow begins with assuming the simplest structure, where a single line serves as heat source. Next, the heat source is endowed with freedom to change its shape as it grows. The objective of the numerical simulations is to discover the geometric features that lead to the fastest melting process. The results show that the heat transfer rate density increases as the complexity and number of degrees of freedom of the structure are increased. Furthermore, the angles between heat invasion lines have a minor effect on the global performance compared to other degrees of freedom: number of branching levels, stem length, and branch lengths. The effect of natural convection in the melt zone is documented. (C) 2016 Elsevier Ltd. All rights reserved.

Several vortex generator shapes are used to increase heat and mass transfer in open and internal flows. Here we report a three-dimensional numerical study investigating the effects of longitudinal and transverse vortices on the heat and mass transfer mechanisms generated by rows of trapezoidal vortex generators. The turbulent macrostructures of these streamwise vortices appear greatly to enhance radial convective transfer. Due to Kelvin-Helmholtz instability, the shear layer shed from the tab's edge becomes unstable and generates periodic transverse vortices that enhance fluid mixing and heat transfer. A global performance analysis of the high-efficiency vortex (HEV) heat exchanger designed to exploit these embedded vortices, shows that the HEV is very competitive with other multifunctional heat exchangers/reactors, especially due to its very low energy consumption. (C) 2010 Elsevier Ltd. All rights reserved.

Members of the CLC protein family of Cl(-) channels and transporters display the remarkable ability to function as either chloride channels or Cl(-)/H(+) antiporters. Due to the intracellular localization of ClC-6 and ClC-7, it has not yet been possible to study the biophysical properties of these members of the late endosomal/lysosomal CLC branch in heterologous expression. Whereas recent data suggest that ClC-7 functions as an antiporter, transport characteristics of ClC-6 have remained entirely unknown. Here, we report that fusing the green fluorescent protein (GFP) to the N terminus of ClC-6 increased its cell surface expression, allowing us to functionally characterize ClC-6. Compatible with ClC-6 mediating Cl(-)/H(+) exchange, Xenopus oocytes expressing GFP-tagged ClC-6 alkalinized upon depolarization. This alkalinization was dependent on the presence of extracellular anions and could occur against an electrochemical proton gradient. As observed in other CLC exchangers, ClC-6-mediated H(+) transport was abolished by mutations in either the "gating" or "proton" glutamate. Overexpression of GFP-tagged ClC-6 in CHO cells elicited small, outwardly rectifying currents with a Cl(-)I(-) conductance sequence. Mutating the gating glutamate of ClC-6 yielded an ohmic anion conductance that was increased by additionally mutating the "anion-coordinating" tyrosine. Additionally changing the chloride-coordinating serine 157 to proline increased the NO(3)(-) conductance of this mutant. Taken together, these data demonstrate for the first time that ClC-6 is a Cl(-)/H(+) antiporter.

WOS:000356176100036; International audience; Here, we report the numerical study of time dependent storage of energy by melting a phase change material. The heating is provided along invading lines, which change from single-line invasion to tree-shaped invasion. The numerical simulations show that the history of the amount of melted material is S-shaped. We also found that the fastest melting (i.e., the steepest S curve) is discovered by allowing the tree architecture to morph freely, toward greater access over time. The stem length and branching angle of invading trees can be selected such that the complete melting process is shorter. The melting process can also be made faster by increasing the complexity of the tree structure. (C) 2015 AIP Publishing LLC.