A Demo-Oriented early NEutron Source (DONES) facility for material irradiation with nuclear is currently being designed. DONES aims to produce neutrons with fusion-relevant spectrum and fluence by means of D−Li stripping reactions occurring between a deuteron beam impacting a stable liquid lithium flowing film implementing the target. Given the hazard constituted by the liquid lithium inventory and the potential risk of reactions with water, air, and concrete eventually resulting in fire events, the Target Test Cell (TTC) is filled with helium and the reinforced concrete walls forming the bio-shield are covered with steel liners. A loss of Li in TTC, due to a large break in the Quench Tank, is postulated, and consequences are deterministically studied. With the TTC liner being water-cooled, the impact of the liner temperature rise following a leakage event is evaluated. Two separate MELCOR code models have been defined for the liquid lithium loop and water-cooled loop and are numerical... [more]

Energy demand forecasting is practiced in several time frames; different explanatory variables are used in each case to serve different decision support mandates. For example, in the short, daily, term building level, forecasting may serve as a performance baseline. On the other end, we have long-term, policy-oriented forecasting exercises. TIMES (an acronym for The Integrated Markal Efom System) allows us to model supply and anticipated technology shifts over a long-term horizon, often extending as far away in time as 2100. Between these two time frames, we also have a mid-term forecasting time frame, that of a few years ahead. Investigations here are aimed at policy support, although in a more mid-term horizon, we address issues such as investment planning and pricing. In this paper, we develop and evaluate statistical and neural network approaches for this mid-term forecasting of final energy and electricity for the residential sector in six EU countries (Germany, the Netherlands, S... [more]

The effectiveness of matrix acidizing using CO2 foamed acid is dependent on the duration of foam stability. This paper presents a supercritical CO2 foamed acid with a surfactant mixture to improve the foam stability in carbonate matrix acidizing. The experimental apparatus was developed to conduct foam-stability and wormhole-propagation tests under high-pressure and high-temperature (HPHT) conditions. The foam decay times of five types of surfactants were measured under atmospheric conditions. Trimax (blend of cocamidopropyl betaine, disodium cocoamphodiacetate, and amine oxide) and Aromox C/12W (coco bis-(2-hydroxyethyl) amine oxide) had a high foam decay time. The surfactant mixture was prepared using these two surfactants. The foam stability tests of the surfactant mixture were performed according to the HCl concentration, surfactant mixing ratio, and injection rate of HCl under HPHT conditions. As a result, the foam stability could be improved by adding an HCl concentration of 20%... [more]

This study presents a novel approach for discovering actionable knowledge and exploring data-based models from data recorded by household smart meters. The proposed framework is supported by a machine learning architecture based on the application of data mining methods and spatial analysis to extract temporal and spatial restricted clusters of characteristic monthly electricity load profiles. In addition, it uses these clusters to perform short-term load forecasting (1 week) using recurrent neural networks. The approach analyses a database with measurements of 1000 smart meters gathered during 4 years in Guayaquil, Ecuador. Results of the proposed methodology led us to obtain a precise and efficient stratification of typical consumption patterns and to extract neighbour information to improve the performance of residential energy consumption forecasting.

Self-contained hydraulic cylinders have gained popularity in the recent years but have not been implemented for high power articulated hydraulic manipulators. This paper presents a novel concept for an electro-hydrostatic actuator applicable to large hydraulic manipulators. The actuator is designed and analyzed to comply with requirements such as load holding, overload handling, and differential flow compensation. The system is analyzed during four quadrant operation to investigate energy efficiency and regenerative capabilities. Numerical simulation is carried out using path control and 2DOF anti-swing of a hydraulic crane as a load case to illustrate a real world scenario. A comparison with traditional valve-controlled actuators is conducted, showing significantly improved efficiency and with similar dynamic response, as well as the possibility for regenerating energy.

The Remedial Action Scheme (RAS) is designed to take corrective actions after detecting predetermined conditions to maintain system transient stability in large interconnected power grids. However, since RAS is usually designed based on a few selected typical operating conditions, it is not optimal in operating conditions that are not considered in the offline design, especially under frequently and dramatically varying operating conditions due to the increasing integration of intermittent renewables. The deep learning-based RAS is proposed to enhance the adaptivity of RAS to varying operating conditions. During the training, a customized loss function is developed to penalize the negative loss and suggest corrective actions with a security margin to avoid triggering under-frequency and over-frequency relays. Simulation results of the reduced United States Western Interconnection system model demonstrate that the proposed deep learning−based RAS can provide optimal corrective actions f... [more]

Finding a numerical method to model solute transport in porous media with high heterogeneity is crucial, especially when chemical reactions are involved. The phase space formulation termed the multi-advective water mixing approach (MAWMA) was proposed to address this issue. The water parcel method (WP) may be obtained by discretizing MAWMA in space, time, and velocity. WP needs two transition matrices of velocity to reproduce advection (Markovian in space) and mixing (Markovian in time), separately. The matrices express the transition probability of water instead of individual solute concentration. This entails a change in concept, since the entire transport phenomenon is defined by the water phase. Concentration is reduced to a chemical attribute. The water transition matrix is obtained and is demonstrated to be constant in time. Moreover, the WP method is compared with the classic random walk method (RW) in a high heterogeneous domain. Results show that the WP adequately reproduces a... [more]

The article presents a new approach to the analysis of the stability of automatic systems with discrete links. In almost all modern automatic control systems (ACS), there are links that break signals in time. These are power controlled switches—transistors or thyristors operating in a pulsed mode and digital links in regulators. Time discretization significantly affects the stability of processes in the automatic control system. The theoretical analysis of such systems is rather complicated and requires a significant change in engineering approaches to analysis. With the improvement of digital controllers and a significant increase in their performance, this problem has practically been forgotten. However, its mathematical “content” has not changed since the 1980s when discreteness began to play a major role in hindering the transition to digital automatic control systems. In this paper, we propose a new approach that consists of interpreting the sampling operation by a link with the p... [more]

In Mexico, as in the rest of the world, the industry sector is frequently highly dependent on fossil fuels; in addition, energy transformation processes are not very efficient and scarcely oriented towards climate change mitigation. Given these facts, solid biofuels (SBFs) from agricultural and forestry residues from rural areas may represent an alternative that contributes to the decarbonization of the industrial sector, especially in Small- and Medium-Sized Enterprises (SMEs). From an economic and climate change mitigation perspective, this study evaluates harnessing SBFs in SMEs related to lime, bricks, dairy products, craft beer, and artisanal mezcal (a well-known Mexican distilled alcoholic beverage), products mainly manufactured in rural areas of Mexico. For each of these SMEs, we constructed two energy consumption scenarios that span from 2018 to 2050. On the one hand, a baseline scenario (BS) that reflects the behaviour of historical energy consumption in Mexico and, on the oth... [more]

Mounting offshore renewable energy installations often involves extra risk regarding the safety of navigation, especially for areas with high traffic intensity. The decision-makers planning such projects need to anticipate and plan appropriate solutions in order to manage navigation risks. This process is referred to as “environmental impact assessment”. In what way can these threats be reduced using the available Automatic Identification System (AIS) tool? This paper presents a study of the concept for the methodology of an a posteriori vessel traffic description in the form of quantitative and qualitative characteristics created based on a large set of historical AIS data (big data). The research was oriented primarily towards the practical application and verification of the methodology used when assessing the impact of the planned Offshore Wind Farm (OWF) Baltic II on the safety of ships in Polish Marine Areas, and on the effectiveness of navigation, taking into account the existin... [more]

A sustainability assessment regarding the manufacturing process and the use of a new proton exchange membrane fuel cell (PEMFC), specially designed for portable hydrogen applications, is presented. The initial fuel cell prototype has been configured by taking into account exclusively technical issues. However, a life cycle analysis considering environmental and socioeconomic impacts is crucial to improve the model to develop a more sustainable product. From the environmental perspective, the durability of the system and its efficiency are key elements required to decrease the potential overall impacts. High electricity consumption for manufacturing requires a commitment to the use of renewable energies, due to the high current value of the projected impact of climate change (42.5 tonnes of CO2 eq). From the socioeconomic point of view, the dependence of imported components required for the synthesis of some materials displaces the effects of value added and employment in Spain, potenti... [more]

In this paper, a distributed energy storage design within an electric vehicle for smarter mobility applications is introduced. Idea of body integrated super-capacitor technology, design concept and its implementation is proposed in the paper. Individual super-capacitor cells are connected in series or parallel to form a string connection of super-capacitors with the associated management unit to form a panel. These super-capacitor panels are shaped to fit the alternative concept of vehicle design, and it solves the design issues and prepares for configurable electric vehicles. Body integration of super-capacitors enhances the acceleration, and regenerative braking performances of the electric vehicle increases the operating life of the Li-ion battery and improves space utilization by giving more area for the main energy source, the Li-ion battery. Integrating super-capacitor into the car body involves special packaging technology to minimize space and promotes distributed energy storag... [more]

The non-pneumatic tire (NPT) is a type of wheel whichdevelopment is related to the beginning of automotive development. The non-pneumatic tire (NPT) is a type of tire that does not contain compressed gases or fluid to provide directional control and traction. Nowadays, this type of wheel is more and more often used in special purpose vehicles, e.g., in military vehicles and working machines. The main feature of the non-pneumatic tire is a flexible support structure (including the part of the wheel between the tread and the rim). This paper presents the results of research aimed at determining the influence of the geometry of the NPT’s (intended for All-Terrain Vehicle−ATV/Utility Task Vehicle−UTV) load-bearing structure on its quasi-static directional characteristics. The experimental tests included the determination of the radial stiffness of research objects on a non-deformable flat surface and on a single obstacle, as well as the determination of the degree of deformation for the el... [more]

The effect of NH3 in H2 and in air was investigated at various concentrations ranging from 1.0 ppm to 100 ppm in air and ranging from 0.25 ppm to 10 ppm in fuel. The effect of NH3 on cathode caused an instantaneous decrease in cell voltage which dropped from 0.734 V to 0.712 V in 30 h and drop rates was 0.73 mV/h for 1 ppm; however, the cell voltage dropped to 0.415 V in 1 h for 100 ppm of NH3. The voltage could not be recovered after the polarization test (V-I test) but could be recovered to 84.4% after operation with neat air for 1.5 h and 98.4% after cycle voltammogram (CV). It was found that the voltage drop was obvious, and the drop rate increased with the NH3 concentration in H2. The voltage drop rates at 500 mA/cm2 were 0.54 mV/h for 0.5 ppm of NH3, 0.8 mV/h for 1 ppm, and 2 mV/h for 10 ppm. The voltage could be recovered from 70.6% to 77.3% after discharged with high purity H2 for 24 h, to 92.8% after being purged with clean air for 10 h and to 98.4% after CV scan. The toleranc... [more]

In marine applications, a cyclic varying pitch (CVP) propeller is a propeller in which the propeller blade can be cyclic-pitched. This cyclic pitching of the propeller blades is used to adapt to the local flow conditions in the non-uniform wake field that the propeller operates in, behind the ship hull. This has the potential to improve the performance of the propulsion system relative to a propeller which has fixed pitch for each revolution. The potential performance improvements include increasing the propulsion efficiency and reducing the cavitation, pressure pulses, vibrations and noise problems. However, the CVP propeller is not on the market today, and several challenges have to be addressed before the CVP propeller may be realized. One of these challenges is how to design the individual cyclic pitch mechanism for the propeller. However, before the cyclic pitch mechanism can be designed, it is necessary to know the requirements for it, such as the required pitching power and torq... [more]

In order to improve the accuracy of the multiple load forecasting of a regional integrated energy system, a short-term multiple load forecasting model based on the quantum weighted GRU and multi-task learning framework is proposed in this paper. Firstly, correlation analysis is carried out using a maximum information coefficient to select the input of the model. Then, a multi-task learning architecture is constructed based on the quantum weighted GRU neural network, and the coupling information among multiple loads is learned through the sharing layer in order to improve the prediction accuracy of multiple loads. Finally, the PSO algorithm is used to optimize the parameters of the quantum weighted GRU. The simulation data of a regional integrated energy system in northern China are used to predict the power and cooling loads on summer weekdays and rest days, and the results show that, compared with the LSTM, GRU and single task learning QWGRU models, the proposed model is more effectiv... [more]

In this study the NOx reduction capability of reburning three biomasses (i.e., wood pellet, torrefied biomass, and empty fruit bunch) via 12 cases (i.e., four reburning ratios for every biomass) is investigated in a 1 MWth-scale pilot-scale furnace. These reburning cases are compared with 12 cofiring cases presented in the Part 1 paper on a consistent basis. It is found that, for every cost to purchase and prepare biomass, reburning technology provides significantly better NOx abatement performance than cofiring (up to 3.4 times). NOx reduction effectiveness as high as 4.9 could be achieved by reburning, which means the percent of NOx abatement could be 4.9 times higher than the percent of reburning ratio. It is found that the highest NOx reduction per thermal unit of biomass happens at the lowest reburning ratio, and increasing the reburning ratio leads to a reduction in NOx abatement effectiveness in an exponential decay manner. Unlike cofiring technology, reburning was found to have... [more]

Since existing residential buildings are a significant global contributor to energy consumption and greenhouse gas (GHG) emissions, any serious effort to reduce the actual energy and carbon emissions of the building sector should explicitly address the carbon mitigation challenges and opportunities in the building stock. This research investigates environmentally and economically sustainable retrofit methods to reduce the carbon footprint of existing residential buildings in the City of Greater Dandenong as a case study in Metropolitan Melbourne, Australia. By categorizing energy use into various building age brackets and dwelling types that align with changes in energy regulations, we identified various retrofit prototypes to achieve a targeted 6.5-star and 8-star energy efficiency rating (out of a maximum 10-star rating system). The corresponding operational energy savings through different retrofit options are examined while also considering the quantity of materials required for ea... [more]

In high-speed magnetic railways, it is necessary to create the forces that lift the train. This effect is achieved by using active (EMS) or passive (EDS) magnetic systems. In a passive system, suspension systems with permanent magnets arranged in a Halbach array can be used. In this paper, an original Halbach array with various alternately arranged horizontally and vertically magnetized magnets is proposed. Correctly selected geometry allows us to obtain higher values of levitation forces and lower braking forces in relation to a system with identical horizontally and vertically magnetized elements. The effect of such a shape of the magnetic arrangement is the reduction of instantaneous power consumption while traveling due to the occurrence of lower braking forces. In order to perform a comparative analysis of the various geometries of the Halbach array, a simulation model was developed in the ANSYS Maxwell program. The performed calculations made it possible to determine the optimal... [more]

According to the engineering phenomenon of the galloping of ice-coated transmission lines at certain wind speeds, this paper proposes a novel type of energy harvester based on the galloping of a flexible structure. It uses the tension generated by the galloping structure to cause periodic strain on the piezoelectric cantilever beam, which is highly efficient for converting wind energy into electricity. On this basis, a physical model of fluid−structure interaction is established, and the Reynolds-averaged Navier−Stokes equation and SST K -ω turbulent model based on ANSYS Fluent are used to carry out a two-dimensional steady computational fluid dynamics (CFD) numerical simulation. First, the CFD technology under different grid densities and time steps is verified. CFD numerical simulation technology is used to simulate the physical model of the energy harvester, and the effect of wind speed on the lateral displacement and aerodynamic force of the flexible structure is analyzed. In addit... [more]

This paper presents the results of experimental tests of the impulse response of selected, essential components of a drone. A standardized lightning pulse that is often used during immunity tests of electronic devices in the aviation industry was applied. A single-stroke voltage impulse generator, MIG0618SS, was capable of producing the desired pulses. The input voltage was injected into selected electronic circuits of the drone system and pulses were observed in different parts of the machine. This allowed us to build a model based on the transmittance of the circuits most exposed to lightning overvoltages. The conducted tests were supported by impedance measurements carried out with an LCR-8110G meter. The obtained results made possible the development of a preliminary drone simulation model, allowing us to determine the size of the disturbances arising in individual circuits during nearby lightning. A discussion of the influence of close lightning discharges on expected induced over... [more]

The development of wind energy and the increasing number of installed wind turbines make it necessary to assess them in terms of the nuisance of the emitted infrasound noise generated by such devices. The article presents the results of measurements and analyses of infrasound emitted during the operation of wind turbines installed in various locations in Poland. Comparative analysis of noise levels in the infrasound and audible range has shown that acoustic energy is mainly in the low and infrasound frequency range, and the measured levels depend significantly on the weighting curves used. On the basis of the results, it was confirmed that the sound pressure level of infrasound signals emitted by the operation of high-power wind turbines, regardless of wind velocity, weather conditions, design solutions of turbines, operating time, rated capacity, does not exceed the criteria specified in the applicable legislation dealing with the assessment of infrasound noise on the working environm... [more]

Despite their simplicity, photovoltaic (PV) modules are often arranged in structures that can be affected by severe and complex wind loads: in this context, the wind flow and the dynamic excitation induced by vortex shedding can introduce unexpected aeroelastic responses. This work introduces a novel wind tunnel application of experimental techniques to address this issue by the use of flow visualisation and video postprocessing, through the optical flow algorithm. Numerical simulations based on unsteady Reynolds-averaged Navier−Stokes (RANS) models are performed and compared against the experimental wind tunnel tests on a PV panel that was also instrumented with pressure taps. A setup with a 65∘ tilt angle was examined because, based on preliminary analyses, it was considered interesting for the free flow−wake transition associated with the dynamic response of the PV panel. The comparison of the experimental and numerical average wind fields supported that the proposed optical flow me... [more]

Laboratory measurements and analyses conducted in a wide range of changes of water temperature and mass flow rate for different types of radiators allowed to provides limitations and assessment of the current radiators heat transfer model according to EN 442. The inaccuracy to determinate the radiator heat output according to EN 442, in case of low water mass flow rates may achieve up to 22.3% A revised New Extended Heat Transfer Model in Radiators NEHTMiRmd is general and suitable for different types of radiators both new radiators and radiators existing after a certain period of operation is presented. The NEHTMiRmd with very high accuracy describes the heat transfer processes not only in the nominal conditions—in which the radiators are designed, but what is particularly important also in operating conditions when the radiators water mass flow differ significantly from the nominal value and at the same time the supply temperature changes in the whole range radiators operating during... [more]

The previously developed approaches for fuel droplet heating and evaporation processes, mainly using the Discrete Multi Component Model (DMCM), are investigated for the aerodynamic combustion simulation. The models have been recently improved and generalised for a broad range of bio-fossil fuel blends so that the application areas are broadened with an increased accuracy. The main distinctive features of these models are that they consider the impacts of species’ thermal conductivities and diffusivities within the droplets in order to account for the temperature gradient, transient diffusion of species and recirculation. A formulation of fuel surrogates is made using the recently introduced model, referred to as “Complex Fuel Surrogate Model (CFSM)”, and analysing their heating, evaporation and combustion characteristics. The CFSM is aimed to reduce the full composition of fuel to a much smaller number of components based on their mass fractions, and to formulate fuel surrogates. Such... [more]