Heavy Transport Research Articles

Уточнение модели концентрационной конвекции в пористой среде с учетом иммобилизации примеси и слабой закупорки

The influence of weak clogging on the process of a heavy impurity transport through a horizontal layer of a porous medium is studied. A constant concentration drop is set at the boundaries of the layer, the flow along the layer is maintained by a constant pressure drop. The present problem is a concentration analog of the well-known Horton-Rogers-Lapwood (HRL) problem. The equations describing the transport of the impurity taking into account the deposition (immobilization) of the impurity particles on the porous skeleton are obtained. The deposition process is described in the framework of the well-known linear sorption model (linear MIM model). Clogging is assumed to be weak in the sense that the influence of deposited particles on porosity is considered to be negli-gible and is taken into account only with respect to the reduction of the permeability of the medi-um. It is found that the basic solution to this system admits the regime of stationary filtration along the layer. In this case, the impurity distribution is linear, which coincides with the known HRL so-lution. The stability of the basic state is analyzed numerically. Neutral curves as well as minimum values of critical parameters (Rayleigh-Darcy number, wave number, and frequency) depending on the system parameters are obtained and analyzed. It is shown that the arising instability, as in the HRL problem, is oscillatory by nature. Taking into account the clogging (along with taking into ac-count the deposition) leads to an increase in the stability of the stationary filtration flow and attenu-ation of the oscillations. The study determines the limits of applicability of the linear MIM model, widespread in the literature, that does not taking into account the clogging.

Evaluation of indoor air dose rate based on Cs‐137 depth distribution in surrounding artificially paved surfaces surveyed 10 years after the Fukushima Daiichi nuclear power plant accident

AbstractUnderstanding residual radioactive contamination state and the resulting radiation environment is vital before reconstructing the lives of residents in areas affected by nuclear power plant accidents. In this study, we surveyed the depth profiles of Cs‐137 in three artificially paved ground surfaces: impermeable asphalt, permeable asphalt, and concrete, in areas affected by the Fukushima Daiichi Nuclear Power Plant accident after a period of 10 years and analyzed the gamma‐ray air dose rate distribution in a two‐story wooden house model surrounded by different ground surfaces using the Particle and Heavy Ion Transport code System of the Japan Atomic Energy Agency. The air dose rate distribution tendencies within the building for different surrounding ground surfaces were clarified by analyzing the transport of gamma rays emitted from the Cs‐137 in the ground. Moreover, the shielding effect of an ordinal concrete fence on the indoor air dose rate was analyzed. The analysis showed that the indoor air dose rate was higher in an environment with artificial pavement than in that with a soil surface, and even a simple measure, such as installing an ordinal concrete fence, could significantly reduce indoor radiation dose rates.

Emissions of Hydrogen Isotopes from the Nuclear Muon Capture Reaction in natSi

The energy spectra of protons, deuterons and tritons produced by the nuclear muon capture reaction in natSi were measured at the M1 beam line of Muon Science Innovative Channel (MuSIC) in Research Center for Nuclear Physics (RCNP) using a counter telescope consisting of a Si detector and a CsI(Tl) scintillation detector. The measured energy spectra were consistent with the previous ones. The experimental energy spectra were compared with theoretical model calculations using the Particle and Heavy Ion Transport code System (PHITS). In PHITS, both the dynamical and statistical processes in the nuclear muon capture reaction are described by the Quantum Molecular Dynamics (QMD) or the modified QMD and the Generalized Evaporation Model (GEM), respectively. The PHITS simulation reproduced generally well the measured proton spectrum at emission energies below 20 MeV, while underestimation was seen at emission energies above 20 MeV. The PHITS simulation underestimates remarkably the measured energy spectra of light complex particles (deuterons, tritons, and alpha particles) in the high energy region.

Reducing CO2 emissions in transportation systems: technologies for electric vehicles powering

This paper illustrates innovative transport systems for the power supply of electric vehicles as a replacement for the plug-in system. Different technologies for energy transfer are being developed worldwide: three of them are more mature, but other may come. Nowadays, the mainly three systems under development are the following: overhead cable power supply system, ground contact power supply system and the contactless wireless charging methodology using the Dynamic Wireless Power Transfer system.In particular, the last-mentioned methodology will be described in detail, the materials research experience involved the 'Laboratory of Applied Research for Innovation and Technology Transfer' at the University of Parma.Among the main differences are that recharging technology by aerial contact and the scientific application of ground contact for vehicle recharging has been developed and applied particularly to heavy vehicles such as trucks and buses. On the other hand, the wireless recharging system is tested and applied not only for heavy transport vehicles but also for small transport vehicles such as cars.

Mobile crane selection in project logistics operations using Best and Worst Method (BWM) and fuzzy Measurement of Alternatives and Ranking according to COmpromise Solution (MARCOS)

Statistics on occupational accidents published by international organizations show that mobile cranes are the riskiest heavy equipment among all crane types. The most significant reason for these crane accidents is the decision-makers' wrong selection of mobile cranes. Making misevaluations and selecting improper mobile cranes can cause many problems besides mobile crane accidents. In addition, selecting a mobile crane is a highly complicated decision-making problem, as there are many conflicting criteria and uncertainties. Besides, no commonly accepted criteria set is used to solve this decision-making problem in the literature. The current paper proposes the fuzzy BWM (Best and Worst Method) and fuzzy MARCOS (Measurement of Alternatives and Ranking according to COmpromise Solution) combination as a robust and practical decision-making tool that can overcome many complicated ambiguities. The suggested model has been applied to solve a mobile crane selection problem encountered by a large-scale project logistics and heavy transport company in Turkey. The acquired outcomes demonstrated that technical criteria are more influential than economic and quality criteria. The criterion “Maximum hoist height” in the technical criteria group is the most influential factor in selecting the best mobile crane option. In addition, the A1 Brand-L. 4.2 is the most appropriate alternative to meet the company's requirements. Finally, a comprehensive sensitivity analysis performed to test the validity and applicability of the model approves the robustness of the model.

Identification of Induced Radionuclides Produced from Dental Metals in Proton Beam Therapy for Head and Neck Cancer

To identify the induced radionuclides produced from dental metals in proton beam therapy and investigate the accuracy of the Monte Carlo (MC) simulation by comparing the measured radioactivity. Two dental metals of pure titanium and gold-silver-palladium alloy, commonly used in Japan, were used in this study. The dental metal placed at the center of Spread-out Bragg Peak was irradiated by 150-MeV passive scattering proton beam. The gamma rays emitted from the activated dental metals were measured using a high purity germanium (HPGe) detector. The induced radionuclides were identified from the measured gamma-ray energies. Furthermore, the Particle and Heavy Ion Transport code System v.3.24 and DCHAIN were used for the MC simulation. The measured radionuclides and their radioactivity were compared with the simulation results. In the MC simulation for the activated titanium, vanadium-47, with a half-life of 32.6 minutes had the strongest radioactivity among the induced radionuclides. The energy peaks of gamma rays emitted from titanium-51, scandium-43, scandium-44, and annihilation gamma rays were observed for the activated titanium in the HPGe detector. In the MC simulation for the activated gold-silver-palladium alloy, silver-108, with a half-life of 2.4 minutes had the strongest radioactivity. The energy peaks of gamma rays emitted from silver-104, silver-104 m, silver-108, and annihilation gamma rays were observed for the activated gold-silver-palladium alloy in the HPGe detector. Furthermore, the induced radionuclides and their radioactivity in the MC simulation were consistent with the measurement results for both dental metals, except for a few radionuclides. We identify the induced radionuclides produced from 2 dental metals and compared their radioactivity between the measurements and the MC simulation. Although the identification of the induced radionuclides using the MC simulation remains uncertain, the MC simulation can be clinically effective for pre-estimating the induced radionuclides in proton beam therapy.

A two-dimensional analytical model for heavy metal contaminants transport in permeable reactive barrier.

Permeable reactive barrier (PRB) remediation technology has been widely used in the remediation of groundwater contamination. In numerical simulations, neglecting the non-uniform distribution of heavy metal contamination along the depth may lead to deviations between simulation results and reality. The distribution of heavy metals in the soil layer around a non-ferrous mining area in Hezhou, Guangxi, southern China was investigated, and it was found that the standard Gaussian function could well describe the non-uniform distribution of heavy metals in the soil layer. A two-dimensional analytical model solved by the finite element method was used to simulate the migration process of heavy metal contamination in the aquifer and PRB. The results show that the uniform distribution of contaminants along the depth ignores the dilution effect, which may underestimate the service life of the PRB and lead to an overly conservative design of the PRB. The breakthrough time of the PRB decreases with the increase of the maximum initial concentration (Cin,max) and the high concentration range (σ), and increases almost linearly with the barrier thickness (Lw). An optimal design method for PRB location and thickness is proposed, which can provide a reference for the engineering application of PRB.

Influence and Mechanism Study of Ultrasonic Electric Power Input on Heavy Oil Viscosity

The reserves of heavy oil are enormous. However, its high viscosity and other characteristics make heavy oil extraction and transportation extremely difficult. Power ultrasonic (US) reforming technology on heavy oil has the advantages of environmental protection and fast results, so it is important to understand the mechanism of ultrasonic reforming. We examine the influence law of the electric power input of the US transducer on the viscosity of heavy oil. Fourier Transform Infrared Spectrometer (FTIR) and Gas Chromatography (GC) are applied to explain the changes in different functional groups, heavy components, and carbon chains before and after US irradiation. The cavitation noise method is also used to study the influences of variance in the intensity of cavitation on the viscosity of heavy oil. The results indicate that the viscosity of heavy oil first decreases, and next increases with an increase in electric power. The functional groups and chromatographic distillation also change in different forms, and with an increase in electric power, the cavitation effect is gradually enhanced. These findings suggest that it is not that the stronger the cavitation, the greater the influence on the viscosity of heavy oil.

Obiekty dystrybucji paliw – HRS

The European Commission's strategy to achieve climate neutrality by 2050 aims at reducing the consumption of fossil fuels and improve air quality, especially in cities. One way to achieve this goal is to decarbonize the economy, including the transport sector, which is crucial for companies in terms of global supply chains. Many experts believe that the zero emission and low emission hydrogen used in electric vehicles with hydrogen fuel cells is the key to meeting this challenge in passenger and heavy duty transport including land, sea and air transport. However, for hydrogen to become a commonly used fuel in transport, it is necessary to develop the essential infrastructure and adequate legal regulations. The paper presents the genesis of the creation of hydrogen fuel distribution facilities, and indicates the key aspects of the implementation of hydrogen fuels in the world, in Europe and in Poland. The paper also discusses the data available on the number of facilities distributing this type of fuel owned by gas and oil corporations that want to achieve climate neutrality and, at the same time, have to provide transport fuels for recipients. It was found that the energy transformation and the type of energy carriers and motor fuels used to power motor vehicles will be related to the change and evolution of fuel distribution facilities.

Effect of ammonium based ionic liquids on the rheological behavior of the heavy crude oil for high pressure and high temperature conditions

Heavy crude oil (HCO) production, processing, and transportation forms several practical challenges to the oil and gas industry, due to its higher viscosity. Understanding the shear rheology of this HCO is highly important to tackle production and flow assurance. The environmental and economic viability of the conventional methods (thermal or dilution with organic solvents), force the industry to find an alternative. The present study was constructed to investigate the effect of eco-friendly ionic liquids (ILs) on the HCO's rheology, at high temperature and high pressure. Eight different alkyl ammonium ILs were screened for HCO's shear rheology at the temperatures of 25–100 °C and for pressures 0.1–10 MPa. The addition of ILs reduced the HCO's viscosity substantially from 25 to 33% from their original HCO viscosity. Also, it aids to reduce the yield stress to about 15–20% at all the studied experimental conditions. Furthermore, the viscoelastic property of the HCO was studied for both strain-sweep and frequency-sweep and noticed the ILs helps to increase HCO's loss modulus (G″) by reducing storage modulus (G′), it leads to the reduction of the crossover point around 25–32% than the standard HCO. Mean the ILs addition with HCO converts its solid-like nature into liquid-like material. Besides, the effect ILs chain length was also studied and found the ILs which has lengthier chain length shows better efficiency on the flow-ability. Finally, the microscopic investigation of the HCO sample was analyzed with and without ILs and witnessed that these ILs help to fragment the flocculated HCO into smaller fractions. These findings indicate that the ILs could be considered as the better alternative for efficient oil production, processing, and transportation. • Aliphatic ionic liquids reduce the viscosity of heavy oil significantly. • Ionic liquid with [HSO 4 ] - or [H 2 PO 4 ] - anion shows better efficiency. • Ionic liquids addition with heavy oil converts its solid-like nature into liquid-like material. • Ionic liquids helps fragment the flocculated heavy oil into a smaller fraction. • Greater the chain length of ionic liquid, higher is the tendency on improving flow-ability.

Existence of finite and anisotropic heavy ion parallel compressibility pinch in the gyrokinetic turbulence

Turbulence-driven heavy ion transport in hot magnetized plasma is investigated by means of the gyrokinetic theory and simulations. A finite heavy ion parallel compressibility pinch (${\mathrm{\ensuremath{\Gamma}}}_{s,\ensuremath{\parallel}}$) is found in the gyrokinetic framework, in contrast to the conventional understanding that ${\mathrm{\ensuremath{\Gamma}}}_{s,\ensuremath{\parallel}}$ is negligible. A perturbation theory clarifies the turbulence frequency dependence of ${\mathrm{\ensuremath{\Gamma}}}_{s,\ensuremath{\parallel}}$, resolving the discrepancy with experimental observations. It is also predicted by a nonlocal approach of the parallel advection term that ${\mathrm{\ensuremath{\Gamma}}}_{s,\ensuremath{\parallel}}$ is strongly anisotropic on a magnetic surface. The parameter dependence shows that decreasing the heavy ion mass ${m}_{s}$ strongly enhances ${\mathrm{\ensuremath{\Gamma}}}_{s,\ensuremath{\parallel}}$ through kinetic effects, leading to a deviation from the $1/{m}_{s}$ scaling. Moreover, the pinch direction can be reversed in nonlinear trapped electron mode turbulence through the inverse cascade.

Simulation and analysis of the secondary-particle-induced background of the follow-up x-ray telescope onboard Einstein Probe

The Einstein Probe (EP) is a small scientific satellite committed to time-domain astronomy and high-energy astrophysics. One of the main payloads in the EP is the Follow-up X-ray Telescope (FXT). To get a quantity of in-orbit data as a reference, data from the Insight-Hard X-ray Modulation Telescope (Insight-HXMT) were adopted. The Insight-HXMT is dedicated to perform hard x-ray all-sky surveys, which has a parallel in-orbit environment with the EP. In this paper, we simulated the in-orbit background of an FXT by the Particle and Heavy-Ion Transport code System, which is the first general-purpose heavy ion transport Monte Carlo code, which has a simulated range from 0.01 meV to 1 TeV. The influence from protons in the EP orbital environment and the secondary rays caused by the shielding materials around the detector have been mainly considered. The Super Monte Carlo Simulation Program for nuclear and radiation Processes has been used to define the materials of the shielding structure. An isotropic source of protons and a complete shielding structure have been constructed in this simulation. First, the spectrum of background between 0.5 and 15 keV has been calculated. Second, we simulated the types of reactions and the fluxes of secondary particles, and all of them were calculated with the same model in the first step. Finally, we considered the effectiveness of the outermost shielding with different materials. Among the calculated spectra of background, we found two conspicuous energy responses with high counts, separately located in 7.345 keV (5 eV) and 8.045 keV (5 eV). Compared with the in-orbit data from the low energy x-ray telescope in the Insight-HXMT, the simulated results are credible. Considering the combination of the simulated types of reactions and fluxes of secondary particles, we could mostly judge that the secondary photons brought the photoelectric effects, which caused the two conspicuous responses in the spectrum of background. In addition, copper was the most suitable material for the outermost shielding in this simulation.

Operation of a circular economy, energy, environmental system at a wastewater treatment plant

Decarbonising economies and improving environment can be enhanced through circular economy, energy, and environmental systems integrating electricity, water, and gas utilities. Hydrogen production can facilitate intermittent renewable electricity through reduced curtailment of electricity in periods of over production. Positioning an electrolyser at a wastewater treatment plant with existing sludge digesters offers significant advantages over stand-alone facilities. This paper proposes co-locating electrolysis and biological methanation technologies at a wastewater treatment plant. Electrolysis can produce oxygen for use in pure or enhanced oxygen aeration, offering a 40% reduction in emissions and power demand at the treatment facility. The hydrogen may be used in a novel biological methanation system, upgrading carbon dioxide (CO 2 ) in biogas from sludge digestion, yielding a 54% increase in biomethane production. A 10MW electrolyser operating at 80% capacity would be capable of supplying the oxygen demand for a 426,400 population equivalent wastewater treatment plant, producing 8,500 tDS/a of sludge. Digesting the sludge could generate 1,409,000 m 3 CH 4 /a and 776,000 m 3 CO 2 /a. Upgrading the CO 2 to methane would consume 22.2% of the electrolyser generated hydrogen and capture 1.534 ktCO 2 e/a. Hydrogen and methane are viable advanced transport fuels that can be utilised in decarbonising heavy transport. In the proposed circular economy, energy, and environment system, sufficient fuel would be generated annually for 94 compressed biomethane gas (CBG) heavy goods vehicles (HGV) and 296 compressed hydrogen gas fuel cell (CHG) HGVs. Replacement of the equivalent number of diesel HGVs would offset approximately 16.1 ktCO 2 e/a. • Curtailed electricity from a 144 MW offshore wind farm can supply a 10MW electrolyser • A 10 MW electrolyser can supply O 2 to a 426,400 person wastewater treatment facility • Only 22% of the H 2 is required for methanation of biogas from sludge digestion • Pure O 2 aeration can result in a 40% reduction in emissions at the treatment facility • Excess H 2 and biomethane could together fuel 390 heavy goods vehicles

Assessment of Intermediate Public Transport as A Feeder System to Metro: A Case of Thane City

Abstract: Metro System is been built to provide the service to its people and scale up the facility provided, this would also require the response of people and shift from their mode of transportation. With heavy transportation and day-to-day increase in the traffic on road there is a need to use the Public Transportation. The Detailed Project Report (DPR) for Thane Metro was made in the year 2017, but there is no feeder plan yet, this gives an opportunity to study this respective field. This dissertation aims at getting to know the responses of the commuters of the metro and also of the operators in the catchment area thus providing an efficient last mile connectivity with the Intermediate Public Transport modes available thereof, the catchment area has been selected in accordance with the Metro Policy, 2019. Road Inventory survey of the area gives a detail information about the physical condition present and help to decide the feeder route. In conclusion, this dissertation will provide a convenient way so as to improve the ridership of metro

Research Priorities and Trends on Bioenergy: Insights from Bibliometric Analysis.

Replacing fossil fuels with bioenergy is crucial to achieving sustainable development and carbon neutrality. To determine the priorities and developing trends of bioenergy technology, related publications from 2000 to 2020 were analyzed using bibliometric method. Results demonstrated that the number of publications on bioenergy increased rapidly since 2005, and the average growth rate from 2005 to 2011 reached a maximum of 20% per year. In terms of publication quantity, impact, and international collaboration, the USA had been leading the research of bioenergy technology, followed by China and European countries. Co-occurrence analysis using author keywords identified six clusters about this topic, which are "biodiesel and transesterification", "biogas and anaerobic digestion", "bioethanol and fermentation", "bio-oil and pyrolysis", "microalgae and lipid", and "biohydrogen and gasification or dark fermentation". Among the six clusters, three of them relate to liquid biofuel, attributing that the liquid products of biomass are exceptional alternatives to fossil fuels for heavy transportation and aviation. Lignocellulose and microalgae were identified as the most promising raw materials, and pretreating technologies and efficient catalysts have received special attention. The sharp increase of "pyrolysis" and "gasification" from 2011 to 2020 suggested that those technologies about thermochemical conversion have been well studied in recent years. Some new research trends, such as applying nanoparticles in transesterification, and hydrothermal liquefaction in producing bio-oil from microalgae, will get a breakthrough in the coming years.

Prediction Method of Heavy Load Wheel/Rail Wear Mechanical Properties Based on GA-BP Hybrid Algorithm

Due to its large axle load and high-density operation mode, heavy haul transportation has greatly improved the cargo transportation capacity, and is receiving unprecedented attention from all countries in the world. Since the development of heavy haul freight transport in China, wheel rail wear has been paid much attention, especially the use of heavy axle load locomotives on upgraded heavy haul lines, which makes reducing wheel rail wear and damage become a technical problem to be solved urgently. Considering that there are too many mechanical parameters involved in the prediction of heavy load wheel rail wear mechanical properties, the prediction accuracy is reduced. Therefore, this paper proposes a method based on GA-BP hybrid algorithm to predict the mechanical properties of heavy load wheel/rail wear. Hertz contact theory is used to simplify the wheel rail contact relationship, and the wheel rail contact model is established. According to the wheel/rail contact model, the expressions of heavy load wheel/rail in the case of vertical, horizontal, direction and gauge irregularity are analyzed, and based on this, a mechanical model of heavy load wheel/rail wear is established. In order to solve the problems of slow convergence speed and easy to fall into local optimum of BP neural network in the prediction of heavy load wheel/rail wear mechanical properties, the global convergence of genetic algorithm is used to optimize the BP network. According to the obtained mechanical parameters of heavy load wheel/rail wear, the mechanical parameters are input into the optimized model, and the relevant prediction results are output. So far, the research on the prediction method of heavy load wheel/rail wear mechanical properties based on GA-BP hybrid algorithm has been realized. The experiment is designed from three aspects of wear degree, hardness and tensile strength, and compared with the measured value, reference [4] method, reference [5] method and reference [6] method to verify the effectiveness of the proposed method. The experimental results show that the predicted results of wear degree, hardness and tensile strength by this method are closer to the measured results. It is proved that the proposed method has higher prediction accuracy and better practical application effect.

Centralized and decentralized electrolysis-based hydrogen supply systems for road transportation – A modeling study of current and future costs

This work compares the costs of three electrolysis-based hydrogen supply systems for heavy road transportation: a decentralized, off-grid system for hydrogen production from wind and solar power (Dec-Sa); a decentralized system connected to the electricity grid (Dec-Gc); and a centralized grid-connected electrolyzer with hydrogen transported to refueling stations (Cen-Gc). A cost-minimizing optimization model was developed in which the hydrogen production is designed to meet the demand at refueling stations at the lowest total cost for two timeframes: one with current electricity prices and one with estimated future prices. The results show that: For most of the studied geographical regions, Dec-Gc gives the lowest costs of hydrogen delivery (2.2–3.3€/kgH2), while Dec-Sa entails higher hydrogen production costs (2.5–6.7€/kgH2). In addition, the centralized system (Cen-Gc) involves lower costs for production and storage than the grid-connected decentralized system (Dec-Gc), although the additional costs for hydrogen transport increase the total cost (3.5–4.8€/kgH2).

Solubility Variation and Prediction Model of CO2 in Water-Bearing Crude Oil.

The solubility of CO2 in water-bearing crude oil is of great significance for the calculation of crude oil reserves, the development of CO2-EOR (CO2-enhanced oil recovery), CO2-CCUS (carbon capture, utilization, and storage), and CO2 assisted steam huff-and-puff technology, and the optimization of the design of CO2 for heavy oil pipeline transportation. In order to determine the variation of the solubility of water-bearing crude oil by injecting CO2 into the formation, taking the Upper Wuerhe Formation reservoir in the 53 East Block as an example, the study of the dissolution characteristics of CO2 in water-bearing crude oil at different temperature and pressure conditions was carried out by using a high-temperature and high-pressure reaction kettle. At the same time, a new solubility prediction model of CO2 in water-bearing crude oil was proposed based on the existing solubility prediction models. The results show that, under the same water cut, the solubility of CO2 in water-bearing crude oil decreases with the increase of temperature and decreases with the decrease of pressure. At the same time, the solubility of CO2 in water-bearing crude oil is more sensitive to pressure. At the same temperature, the solubility of CO2 in water-bearing crude oil decreases with the increase of water cut, and the higher the pressure, the greater the effect of water cut on the solubility of CO2 in water-bearing crude oil. The newly established combined prediction model of CO2 solubility in water-bearing crude oil is convenient for calculation and has a wide range of applications. The average relative error is only 9.5%, which can meet the requirements of engineering calculation accuracy.

Study on the stability of oil-water annular flow under different amplitude

Compared with the traditional transportation of high-viscosity crude oil, water annular transportation has the advantages of low energy consumption and no change in crude oil composition. With the continuous development of marine heavy oil transportation, submarine oil pipelines are inevitably subjected to vibration and impact, affecting the annular flow in the pipeline. In this paper, the VOF model in Fluent software is used to simulate the stability of oil-water annular flow in a horizontal pipeline under different amplitudes and the interface characteristic parameters of annular flow. In addition, the influence of vibration on oil-water annular flow in the horizontal pipeline under different marine environments is studied. The results showed that the vibration parameters have an influence on the flow of oil-water annular flow in the horizontal pipeline. Under the condition of constant inlet velocity, the eccentricity degree of oil core is analyzed to reveal the law that the stability of annular flow decreases with the increase of amplitude. The relationship between the eccentricity of oil core and the vibrational parameters of pipes are explored in this paper. At the same time, the unit pressure drop under the condition of pipe vibration and its mechanism are studied. These results could provide references for parameters optimization of heavy oil-water annular flow transportation under vibration conditions.

Assessing the effectiveness of hydrogen pathways: A techno-economic optimisation within an integrated energy system

With the world still far off-track from averting relentless global warming, and most countries struggling in meeting their self-imposed goals, hydrogen can potentially play a crucial role in tackling the major challenge of decarbonising the global economy in the framework of a sustainable development. Capable to store, carry, and convert energy in a variety of ways, hydrogen can be a versatile tool to exploit fully the potential of renewable energy sources. Using a holistic approach within a techno-economic optimisation, this study aims at analysing quantitatively the effect of different possible energy pathways employing hydrogen, taking the Italian energy system as a case study, assuming a progressive growth in both renewable power generation capacity and electric mobility in private transport. Results confirm the beneficial impact of hydrogen and identify three hydrogen-based pathways in the optimised energy scenarios: production of synthetic natural gas to partially replace natural gas in the grid and both direct hydrogen consumption and production of synthetic liquid fuel in the heavy transport sector. Direct hydrogen injection in the gas grid plays a negligible role instead. At most, CO2 emissions can be reduced by 49% within the investigated scenarios, with an increase in annual costs of 8%.