bluuebunny/crossref_metadata_2025 huggingface dataset:
Conservation voltage reduction based comprehensive power management scheme for an isolated solar photovoltaic battery based microgrid
Authors: Haresh Sabhadia , Das Biswarup , Pant Vinay
Published: February 2019

Use of Battery in standalone system can offer number of benefits in terms of energy management, reduction of dependency on fossil source and voltage regulation. In this study, a power management technique considering conservation voltage reduction (CVR) along with droop control method is proposed for a standalone system supplied from Photovoltaic (PV) source and battery. The proposed power management scheme ensures that under all operating conditions, the battery is neither overcharged nor completely discharged. It further ensures that under no condition, the power limit of battery charging as well as battery discharging controller is exceeded. The proposed method also aims to minimize the size of overall Photovoltaic battery (PVB) system to reduce the total investment and operation cost considering energy saved achieved by CVR, while satisfying system operational constraints. The proposed method also reduces the number of charging/discharging operations of battery to enhance its life. The validity of the proposed power management scheme has been extensively tested on a European distribution system through PSCAD/EMTDC simulation studies as well as on real time digital simulator (RTDS). The simulation results indicate that the combination of CVR and Droop control can achieve appreciable energy savings.
In-depth study of the hypercompact H II region G24.78+0.08 A1
Authors: Cesaroni R. , Beltrán M. T. , Moscadelli L. , Sánchez-Monge Á. , Neri R.
Published: February 2019

Context. The earliest phases of the evolution of a massive star are closely related to the developement of an H II region. Hypercompact H II regions are the most interesting in this respect because they are very young, and hence best suited to study the beginning of the expansion of the ionised gas inside the parental core.

Aims. We have analysed the geometrical and physical structure of the hypercompact H II region G24.78+0.08 A1, making use of new continuum and hydrogen recombination line data (H41α, H63α, H66α, H68α) and data from the literature (H30α, H35α).

Methods. We fit the continuum spectrum with a homogenous, isothermal shell of ionised gas at 104 K and derive the size of the H II region and the Lyman continuum luminosity of the ionising star. We also fit the recombination line spectra emitted from the same shell with a model taking into account expansion at constant speed.

Results. The best fits to the continuum and line spectra allow the derivation of the Lyman continuum luminosity of the ionising star, H II region size, geometrical thickness of the shell, and expansion velocity. Comparison between the 5 cm and 7 mm brightness temperature distributions demonstrates that a thin layer of ionised gas of a few 1000 K at the surface of the H II region is necessary to reproduce the morphology of the continuum emission at both wavelengths.

Conclusions. We confirm that the G24 A1 hypercompact H II region consists of a thin shell ionised by an O9.5 star. The shell is expanding at a speed comparable to the sound speed in the ionised gas. The radius of the H II region exceeds the critical value needed to trap the ionised gas by the gravitational field of the star, consistent with the observed expansion.
Observing the gas component of circumplanetary disks around wide-orbit planet-mass companions in the (sub)mm regime
Authors: Rab Ch. , Kamp I. , Ginski C. , Oberg N. , Muro-Arena G. A. , Dominik C. , Waters L. B. F. M. , Thi W.-F. , Woitke P.
Published: February 2019

Context. Several detections of wide-orbit planet-mass/substellar companions around young solar-like stars were reported in the last decade. The origin of those possible planets is still unclear, but accretion tracers and VLT/SPHERE observations indicate that they are surrounded by circumplanetary material or even a circumplanetary disk (CPD).

Aims. We want to investigate if the gas component of disks around wide-orbit companions is detectable with current (ALMA) and future (ngVLA; sub)mm telescopes and what constraints such gas observations can provide on the nature of the circumplanetary material and the mass of the companion.

Methods. We applied the radiation thermochemical disk code PRODIMO to model the dust and gas component of passive CPDs and produced realistic synthetic observables. We considered different companion properties (mass, luminosity), disk parameters (mass, size, and dust properties) and radiative environments (background fields) and compared the resulting synthetic observables to telescope sensitivities and existing dust observations.

Results. The main criterion for a successful detection is the size of the CPD. At a distance of about 150 pc, a CPD with an outer radius of about 10 au is detectable with ALMA in about six hours in optically thick CO lines. Other aspects, such as the luminosity, disk inclination, and background radiation fields of the companion, are also relevant and should be considered to optimize the observing strategy for detection experiments.

Conclusions. For most of the known wide-orbit planet-mass companions, their maximum theoretical disk size of one-third of the Hill radius would be sufficient to allow detection of CO lines. It is therefore feasible to detect their gas disks and constrain the mass of the companion through the kinematic signature. Even in the case of non-detections such observations provide stringent constraints on disk size and gas mass, and this information is crucial for formation theories.
Sustainable solutions for thermal energy saving in hospital operating theatres
Authors: Sánchez-Barroso Moreno Gonzalo , García-Sanz Calcedo Justo , González Alfonso G. , Salgado David R.
Published: February 2019

Heating, ventilating and air conditioning systems in hospital operating theatres consume high amounts of energy, operate for long periods of time and provide high performance. For this reason, it is necessary to study their energy consumption and determine sustainable solutions that optimize their operation and improve their performance. In this paper, annual thermal energy consumption of a conventional operating theatre is evaluated. Potential energy savings is evaluated by maintaining an adequate indoor environmental quality for these rooms. In addition, how to minimize energy consumption depending on the air renewal flow rate used and installing a sensible heat recovery system was studied. Results show that energy demand of an operating room is reduced by 24.1% by recirculating 25% of air flow extracted from the room. Energy cost decreases 44.31% by increasing the recirculated air flow rate to 50% of the air flow extracted from the room.
Evaluation of the energy efficiency of an industrial consumer in trigeneration mode
Authors: Ionescu Constantin , Tuţică Diana , Pătraşcu Roxana , Dincă Cristian , Slavu Nela
Published: February 2019

The optimization of the energy supply solution of an industrial facility is a main objective of any management program within a company, having as desideratum: quality, safety and flexibility in energy supply. The electricity and heat supply (heat and cold) using a trigeneration plant is a modern technological solution, with high energy efficiency performance and low impact on the environment. Also, this technology is economically efficient, assuring the reduction of the global energy consumption of the industrial society, and implicitly the increasing of the profit. The input data considered in this paper are the values and the characteristics of the demands of the three energy forms belonging to the analysed industrial consumer. The structure of the thermal energy both as heat (technological steam, heating, domestic hot water) and cold (air conditioning) is considered. The consumption of the electricity covers the need of both the technological process and of the buildings (power supply and lighting). In a first stage, the most suitable technological solution for the specific conditions and characteristics of the needs is chosen. The multicriteria analysis of the proposed technological solution is performed during the next stage.
Influence of air velocity on indoor environment quality in unidirectional flow operating theatres: A study based on Computational Fluid Dynamics
Authors: Sánchez-Barroso Moreno Gonzalo , García Sanz-Calcedo Justo , Marcos Romero Alfonso C.
Published: February 2019

It is necessary to characterise air-conditioning airflow in omanuscriprder to optimize hospital Indoor Environment Quality in high-performance operating theatres, and also reduce the risk of nosocomial infection due to pathogen contamination. The aim of this article is to study the prevalence of optimal healthy conditions from controlled air flow quality in hospital facilities, and to minimize energy consumption. To this purpose, the indoor air movement was modelled by Computational Fluid Dynamics technology. The optimal results showed that it is necessary to drive ultra-clean air ranging between 0.25 m/s and 0.40 m/s, values which are adequate to perform efficient sweeping and cleaning of the air near the patient, maintaining unidirectional air flow permanently as the air passes through the surgical field. These speeds must be taken into account as calculation parameters in new hospital facility projects, and as control parameters for the existing operating theatres.
Numerical study of the air distribution in the Crew Quarters on board of the International Space Station
Authors: Berville Charles , Georgescu Matei-Răzvan , Năstase Ilinca
Published: February 2019

The current concept of Crew Quarters on board of the International Space Station has several issues according to the crew member’s feedback. Major issues concern noise levels, the accumulation of CO2 and the quality of the air distribution. Our study targets the airflow distribution, to diagnose this issue, we realise a series of numerical simulations (CFD) based on a real scale replica of the Crew Quarters. Simulations were set with a zero-gravity mode and with the theoretical air parameters inside the SSI. The geometry includes a thermal manikin having the neutral posture of a body in the absence of gravity. Numerical simulations were run for the three different air flow rates provided by the current ventilation system. Results have shown that the air distribution inside the Crew Quarter is insufficient for low airflow rates but becomes acceptable for the higher airflow rate, however the higher airflow rate can potentially produce draught discomfort.
Mesh independency study for an elementary perforated panel part of an air solar collector
Authors: Bejan Andrei-Stelian , Bode Florin , Catalina Tiberiu , Teodosiu Cătalin
Published: February 2019

In order to achieve the numerical model of a transpired solar collector (TSC) with integrated phase changing materials (PCM) it is mandatory to study the impact of the orifice geometry on the entire system. The numerical simulation of the entire solar collector absorber metal plate (1000x2000mm and 5000 orifices) is not feasible thus resulting a huge number of cells for the numerical grid for which we will need very high computational resources and a very large amount of time to be solved. By taking these aspects into account we decided to simulate only four equivalent orifices and then to transpose the results to the actual case for further studies. The present paper aims to analyse the mesh independency study for an elementary perforated panel with four equivalent lobed orifices which is part of a real case TSC. This analysis represents one of the most important stages within the construction of the TSC numerical model and doesn't need an experimental validation. The study was conducted in Ansys Fluent CFD software and the results were processed directly by using Tecplot software. Six different meshes were analysed (from 0.2 to 7.3 million cells), boundary conditions were imposed, and k-ε RNG turbulence model was used according to the literature. After comparing velocity and temperature fields in longitudinal and transverse planes we concluded that from 5.3 million cells the solution is independent of the meshing quality.
Numerical efficiency evaluation of a vertical axis turbine equipped with 4 digits and 5 digits NACA airfoils
Authors: Costea Florina , Malael Ion
Published: February 2019

In the current age of global energy crisis, a run for the use of renewable energy resources as the wind energy has gained a significant attention. The main objective of this study is the comparison between two wind turbine configurations. These two turbines have the same geometric parameters but one with a 4 digits NACA0018 blades and the other with 5 digits NACA63-415 blades. In this scientific paper, a numerical evaluation of the airfoil shape influence on the VAWT efficiency is done. For this study the CFD methods with Ansys Fluent software, are used. All the simulations are for unsteady flow at 1e06 Reynolds number value with SST turbulence model. At the design point the wind velocity is 12 m/s and for the wind turbine geometric features, the diameter is 3.25m and the height 4.87m. The power coefficient variation through tip speed ratio will be represented for each wind turbine configurations. To estimate the recirculation zone effects on the efficiency, the vorticity magnitude contours are presented for different positions of the blades. The results will indicate the feasibility of optimization of future wind turbine more complex airfoils.
Spreadsheet solution for the computation of the mean wind speed and turbulence intensity profiles according to the Romanian standard
Authors: Chiulan Elena-Alexandra , Georgescu Andrei-Mugur , Coşoiu Costin-Ioan , Anton Anton
Published: February 2019

The presented paper focuses on the computation of the mean wind speed and turbulence intensity profiles for all the cities from Romania. The calculation of both, the mean wind speed profile and the turbulence intensity profile, had as mathematical support the equations presented in the Romanian design standard for wind action CR 1-1-4/2012. The main objective of this paper was to provide a tool for the computation of the two wind action features. This method was based on creating a spreadsheet in Excel with which, in just a few seconds, a user could correctly obtain the two wind characteristics. This Excel dashboard can be used as a teaching material for students as well as input data for structural design engineers in the process of modelling and observing the behaviour of a building excited by wind action on a particular city in Romania.
The stability of the radiative regime in Bucharest during 2017-2018
Authors: Budea Sanda , Bădescu Viorel , Ciocănea Adrian , Croitoru Cristiana Verona , Năstase Ilinca
Published: February 2019

The paper presents an analysis of the solar irradiation and the stability of the solar radiative regime, available for Bucharest and the southern area of Romania. The study is based on meteorological data measured at 3.6 seconds, on several consecutive days of each season, in the years 2017 and 2018. Data acquisition was performed at Technical University of Civil Engineering Bucharest. The daily mean values for sunshine number and sunshine stability number are computed and analysed. The analyses carried out in this research are useful for applications of solar energy and conversion to thermal energy in hot air solar collectors to estimate the temperature variation at the collector air outlet as well as for photovoltaic panels to estimate the resulting electrical energy.
Evaluation of the PV energy production determined by measurements, simulation and analytical calculations
Authors: Petreuş Dorin , Bălan Mugur , Pop Octavian , Etz Radu , Patărău Toma
Published: February 2019

The study provides a comparative analysis of the energy production of a 3 kW peak PV array connected in an islanded microgrid, in correlation with solar radiation and ambient temperature measurements. The experimental system is located in Cluj-Napoca Romania and was monitored during the year 2017, based on a graphical user interface. It was also evaluated the capability to predict the PV energy production by using the PV*SOL simulation software and an analytical model, developed at the Technical University of Cluj-Napoca. As input data in the analytical model was used the measured solar radiation and ambient temperature while in the simulations was used alternatively measured data and average meteorological data available in the software database. Besides energy production it was compared the solar radiation on the tilted plane of the PV panels, the PV panel's temperature and the system efficiency. For the predictions accuracy evaluation it was used the weighted mean absolute error based on total energy production, which was found to be lower than 1%, in good agreement with the values reported in literature. The outcomes of this study are valuable for expanding the PV installations in this area and for predictive energy management developments.
Integrated inverse design of ventilation for an aircraft cabin
Authors: Wei Yun , Liu Wei , Xue Yu , Zhai Zhiqiang John , Chen Qingyan Yan , Zhang Tengfei Tim
Published: February 2019

Cabin ventilation is crucial for maintaining thermal comfort and air quality for passengers and crew. The genetic algorithm, proper orthogonal decomposition (POD), and adjoint method have been proposed to inversely design the cabin ventilation. However, each method has its cons and pros. This paper proposed to integrate the above three methods in cascades. The genetic algorithm was applied first in the first stage to roughly circumscribe the ranges of design parameters. Then POD was applied in the next stage to further narrow the ranges and estimate the optimal parametric sets for each design criterion. The estimated optimal design from POD was supplied to the adjoint method for fine tuning. The air-supply parameters of a five-row aircraft cabin were inversely designed to achieve the minimum absolute value of the predicted mean vote (PMV) and the minimum averaged mean age of air. The results showed that the integrated method was able to improve the design stage by stage. The integrated method has superior advantages to assure the optimal design while minimizing the computing expense.
Speed factors computed for pumping schedules in Water Distribution Networks: DDA versus PDA formulations
Authors: Mădulărea Remus Alexandru , Ciuc Petre-Ovidiu , Georgescu Andrei-Mugur , Georgescu Sanda-Carmen
Published: February 2019

This paper focuses on a methodology allowing to derive the pumping schedule in Water Distribution Networks (WDN), upon a time dependent water demand. The selected test case is a previously studied WDN. Two pumping algorithms give different pumping rules. By solving the nonlinear system of equations, consisting of energy balance equations, mass balance equations and pumping rules, one gets the pumps speed factors. Solutions attached to the Pressure Driven Analysis (PDA) correspond to energy and cost savings, with respect to the solutions given by the Demand Driven Analysis (DDA). The methodology described in this paper is simple and rapid, but the iterative numerical method used to solve the system of equations is highly dependent on the starting guess.
EPANET modeling of an urban groundwater field
Authors: Iancu Iulian , Dimache Alexandru-Nicolae , Georgescu Sanda-Carmen , Georgescu Andrei-Mugur
Published: February 2019

The paper presents an EPANET model of a groundwater well field. The method used in the simulations to model the variation of the hydrodynamic levels in wells as a function of the pumped flow rate is discussed, and a comparison to previous simulations that used fixed hydrodynamic levels in the wells is performed. The case study points to a groundwater well field in Romania. The results show that the new method although requiring a more complex EPANET model, provides a solution that is closer to the actual variation of water levels in wells.
Retention basin with Golesti SHPP downstream dam for mitigating hydropeaking and producing green electricity
Authors: Popa Bogdan , Popa Florica , Tică Eliza Isabela , Neagoe Angela , Diminescu Mihaela Amalia
Published: February 2019

Hydropeaking is due to the intermittent operation of peak hydropower plants and leads to various and complex problems downstream. A solution to solve part of them is to provide the development scheme with a retention basin downstream the hydropower plant (HPP). The water used intermittently during the day / week to produce electricity at peak load, which leads to sudden variation of flows into the riverbed will be regulated in this reservoir. Irrespective of the program that the HPP has during the day, the retention basin gathers the water and evacuates it downstream as much as possible constantly during the day or, at least, attenuates the sudden variation, increase or decrease, of levels downstream. Thus, the maximum flows evacuated by the HPP can be dramatically reduced as well as the flow fluctuations and the river levels accordingly. If the flow downstream the retention basin is almost constant during the day and it is released through a small hydropower plant, the positive effect of this reservoir on hydropeaking is combined with the production of green electricity. The subject of this paper is to roughly analyse the possibility to build a retention basin downstream Golesti HPP by means of weir and contour dams, if the case may be, and to release the water constantly or with smooth fluctuations, via one or two turbines, a small hydropower plant, producing green electricity without further harming the riverbed and the ecosystem downstream the weir.
Modelling of CO2 storage in geological formations with DuMux, a free-open-source numerical framework. A possible tool to assess geological storage of carbon dioxide in Romania
Authors: Tatomir Alexandru , Dimache Alexandru-Nicolae , Iulian Iancu , Sauter Martin
Published: February 2019

Geological storage of carbon dioxide represents a viable solution to reduce the greenhouse gases in the atmosphere. Romania has initiatives to build a large-scale integrated CO2 capture and storage demonstration project and find suitable on-shore and off-shore CO2 storage locations. Numerical simulators are essential tools helping the design process. These simulators are required to be capable to represent the complex thermo-hydro-mechanical-chemical and biological phenomena accompanying the geological CO2 storage such as, multi-phase flow, compositional effects due to dissolution of CO2 into the brine, non-isothermal effects due to cold CO2 injection, geomechanical effects, mineralization at the reservoir-scale. These processes can be simulated accurately and efficiently with DuMux (www.dumux.org), a free- and open-source simulator. This article presents and reviews briefly these mathematical and numerical models.
Preventing the natural hazards and protection against floods in a deltaic area
Authors: Popescu Cătalin , Stanca Constantin Alin , Isofache Petruta , Abdulamit Altan
Published: February 2019

The project of preventing the natural hazards and protection against floods of city Babadag has been designed to protect river banks of Tabana brook and its tributaries inside the area of city Babadag, against floods and silting phenomenon. The project contributes to the protection of infrastructure and social economic objectives, being in danger to deteriorate or even to be destroyed if this project will not be implemented. Aside protection of infrastructure and economic objectives, this study has another extremely important purpose for the community protection and improvement of the environmental quality and living standards from the area.
Experimental setup to study two phase flows for environmental applications
Authors: Murgan Irina , Bunea Florentina , Nedelcu Adrian , Ciocan Gabriel Dan
Published: February 2019

The air water mix is a major concern for the environmental application. This paper proposes an experimental method to accede simultaneously at the water flow velocity field and at the void fraction. Instantaneous and mean fields, as well as the evolution with the flow parameters variation are obtained in cavitation or aerated flows. This method allows a good accuracy for the flow velocity fields (2%) and void (vapours or air) contours (4%).
Membrane Bioreactors Used for Treatment of Food Industry Effluents
Authors: Joudah AL-Saadi Anmar , Racoviteanu Gabriel
Published: February 2019

Effluents from the food industry determine pollution problems due to high COD and BOD concentrations. Compared to other industrial divisions, food industry requires large amounts of water. In this study, MBR was based on submerged hollow fibers membranes functioning by low vacuum. Two phases of bioreactor treatment were carried out with different HRTs (2-8) and (2-24) hours. Sixteen water samples collected from the influent and the effluent of the bioreactor during the two phases. NaOCl compound was added during the backwashing process for all tests, and the same compound was added with mixed liquid for the second test at period 24 hour of aeration. The samples were tested for twelve water quality tests: temperature, Dissolved Oxygen, pH, Turbidity, Total Suspended Solids, Mixed Liquor Suspended Solids, Chemical Oxygen Demand, Biochemical Oxygen Demand, Nitrate Nitrogen, Ammonium Nitrogen, Total Phosphate, and Ortho Phosphate. The results indicated that the bioreactor system can be used efficiently to treat industrial wastewater from the food industry. The efficiency of the technology was evaluated with sodium hypochlorite addition to removing the adherent bacteria on the surface area of hollow fibers. The results showed that the bioreactor under the conditions of the second phase was excellent in removing Turbidity, TSS, COD, and BOD5 with a removal efficiency 99.96%, 89.52%, 93.56%, and 99.36% respectively, when added 82 ml of NaOCl in the bioreactor tank, and was a good removing of TP, and Ortho-P with removal efficiency 60.76% and 48.95% respectively. Otherwise, a negative effect of NaOCl on both of NO3-N and NH4-N was obtained in term of removal where the minimum removal efficiency was observed when adding 82 ml of NaOCl under the conditions of the second phase.
Implementation of a geothermal heat pump system in a solar passive house
Authors: Ilisei Gheorghe , Catalina Tiberiu , Alexandru Marian , Gavriliuc Robert
Published: February 2019

Underground energy sources are becoming increasingly popular and now geothermal heat pumps are frequently used to heat/cool different types of buildings, including for solar passive houses. This article aims at giving a contribution in the development of the thermal modelling of borehole heat storage systems, investigating the possibility of a GSHP (ground source heat pump) implementation with vertical boreholes in a solar passive house. A case study analysing a residential solar passive house is presented as a suitable modelling tool for the estimation of the thermal behaviour of GSHP systems by combining the outcome from different modelling programs. The software DesignBuilder, Earth Energy Designer and a sizing method for borehole’s length are used for producing the numerical results. The results highlight that the length of the borehole, a major index in estimating the system’s cost, is directly influenced by fundamental variables like thermal conductivity of grout or soil. Additionally, correlations between these parameters and the coefficient of performance of GSHP were made. Furthermore, the length of borehole is very important as it is responsible for almost half of the total installation cost and triggered a difference in electricity consumption of the GSHP up to 14%.
Current trends in the management of groundwater specific geospatial information
Authors: Ilie Codrina Maria , Gogu Radu Constantin
Published: February 2019

The purpose of this paper is to present the state-of-art of groundwater geospatial information management, highlighting the relevant data model characteristics and technical implementation of the European Directive 2007/2/EC, also known as the INSPIRE Directive. The maturity of the groundwater geodata management systems is of crucial importance for any kind of activity, be it a research project or an operational service of monitoring, protection or exploitation activities. An ineffective and inadequate geodata management system can significantly increase costs or even overthrow the entire activity ([1-3]). Furthermore, following the technological advancement and the extended scientific and operational interdisciplinary connectivity at national and international scale, the interoperability characteristics are becoming increasingly important in the development of groundwater geospatial information management. From paper recordings to digital spreadsheets, from relational database to standardized data models, the manner in which the groundwater data was gathered, stored, processed and visualized has changed significantly over time. Aside from the clear technical progress, the design that captures the natural connections and dependencies between each groundwater feature and phenomena have also evolved. The second part of our paper address the variations that occurred when outlining the different groundwater geospatial information management models, differences that depict the complexity of hydrogeological data.
Analysis of a low-voltage operating microgrid located in a residential area
Authors: El-Leathey Lucia-Andreea , Chihaia Rareş-Andrei , Murgescu Ion , Cîrciumaru Gabriela , Nedelcu Adrian
Published: February 2019

The paper aims at providing the analysis of domestic energy generation and consumption within residential areas. The topic of this study is twofold: theoretical and experimental by addressing aspects related to the operation of a microgrid connected to the low-voltage distribution grid. In order to achieve the power quality analysis for various scenarios, an appropriate testing stand was developed by using the Chauvin Arnoux CA 8435 analyser. There is envisaged the modelling and design of a mixed microgrid characterized by two line sections established by three main energy consumption nodes. There have been integrated several connection points related to the distributed generation sources and to the photovoltaic power plants, respectively, and also several supply points for the household end-users. 13 operation scenarios have been developed and recorded by analysing the voltage variation within the microgrid. Furthermore, the paper envisages the stabilization impact of the microgrid voltage variation in the presence of distributed generation sources.
Efficient energy use and storage practices within residential facilities for compliance with the nZEB criteria
Authors: Murgescu Ion , El-Leathey Lucia-Andreea , Chihaia Rareş-Andrei , Cîrciumaru Gabriela
Published: February 2019

Solar energy, today, is the leader in renewable energy and the world's increasing new energy source. In 2016, for the first time, newly installed photovoltaic capacity has increased by more than 50%, exceeding the new coal-fired power stations capacity established worldwide. At the beginning of the year, the European Parliament agreed the target that 35% renewable sources by 2030. Studies show that by 2050 approximately 45% of all the households in the EU could produce their own renewable energy and more than a third of them could be part of a renewable energy cooperative, despite the worries of the distribution companies. Furthermore, the EPBD directive (EU) - Energy Performance of Buildings pushes towards new and more performing buildings - nearly zero energy buildings (nZEB) - where energy efficiency and energy flexibility are essential to achieve the required performance targets. Nearly zero-energy buildings (NZEBs) have very high energy performance and could be achieved through the integration of renewable and decentralized energy sources, continuous grid optimization and the inclusion of increasing numbers of consumers becoming producers, so called prosumers. So far, the photovoltaic system is the single technology that can combine data from utility networks with household consumption and therefore should be considered a starting point for streamlining the electricity consumption and production which will be imposed by strict regulations.
Monopile foundation under lateral cyclic action. Numerical modelling
Authors: Drăguşin Andrei Valentin , Batali Loretta
Published: February 2019

Foundation of an off-shore wind mill is submitted throughout its existence to a very high number of cycles coming from lateral actions such as waves or wind. These actions have a strong aleatory character which makes them very hard to predict, quantify and analyse. Therefore, in current design practice, these actions are being considered as pseudo-static force at their maximum values, with the cyclic phenomenon being neglected. This can lead to an inappropriate design of the foundation, which could have a negative impact on the future structure. This type of structure is generally built on a monopile foundation, a single, large diameter pile, which will be submitted to thousands lateral cycles. The pile diameter plays an important role, influencing the behaviour of the entire structure. Centrifuge experiments on small-scale models are very useful to study such complex problem as piles under lateral cyclic loads. Several researches have been carried out internationally and the results can be used for calibrating numerical models, which is obviously a more accessible method of design, compared to an experimental approach. This has been precisely the starting point of this paper. The purpose of the present paper is to analyse the influence of the pile diameter, by using a FEM a numerical model, previously calibrated based on centrifuge experiments carried out at IFSTTAR Nantes. For the numerical modelling the software CESAR-LCPC 3D has been used. Several pile diameters have been considered, as follows: 0.72 m, 1.08 m, 1.44 m, 1.80 m, 2.16 m and 2.52 m. The results are taking into account the lateral displacement and bending moment of the piles, for static and cyclic loading. The main objective was to determine the stabilisation rate of the most important two design elements (pile head displacement and maximum bending moment) after “n” cycles and to eventually conclude the diameter value beyond which no more influence of cycles is recorded. The numerical model considered 15 cycles and the results have been used extrapolated in order to determine the cycle “n” of stabilisation (for displacement and bending moment).
The implementation and role of geotechnical data in BIM process
Authors: Berdigylyjov Merdan , Popa Horaţiu
Published: February 2019

Building Information Modeling (BIM) is becoming increasingly important tool in civil engineering both in the infrastructure design and construction process. BIM uses an intelligent model that provides a faster, more economical and less environmental impact for building and managing construction and infrastructure projects. Intelligent information model enable rich visualization, simulation and collaboration, which together allow better decision making throughout the project team. Major infrastructure projects that have a significant geotechnical and structural aspects may implement BIM tools and processes but often seem to neglect the geotechnical aspect of the model. This omission can lead to costly mistakes especially when the project is infrastructure-based. This paper reviews the current BIM implementations on major infrastructure projects and overseas and reviews how the inclusion of the geotechnical data in the BIM model can improve the models usefulness and the decision making process. The paper also investigates the reasons why the geotechnical data is not included and how these barriers can be removed so that the geotechnical and structural teams a fully integrated. The paper ends with a set of recommendations that, if adopted, could allow the engineering design team to produce innovative geotechnical systems and improve the cost effectiveness of construction.
The study of dependency between land-use coverage and parcel boundaries
Authors: Benduch Piotr
Published: February 2019

Land-use constitutes a part of the earth’s surface which is used in a specific, unitary manner. In Poland, data concerning land-uses are registered in the Real Estate Cadastre. This data plays an important role, inter alia, in the context of land properties taxation as well as performing statistical analyses in the field of spatial structure and land development form on various levels of administrative division of a country. Data on land-uses also form basis for activities aimed to agricultural and forest land protection. In this article, the study concerning identification of dependency between parcel boundaries and land-use coverage has been conducted. Occurrence of such a dependency is determined by the characteristics of Polish legal regulations and the fact of carrying out the Real Estate Cadastre in the form of informational system. On this basis it could be concluded that parcel boundary is one of determinants influencing the coverage shape of specific land use form. Using GIS tools, the assessment of size of this impact has been performed at the level of individual land properties as well as the whole cadastral districts. The spatial structure of land-uses in selected cadastral districts in southern Poland has been also compared. The results of analysis were presented both in graphical and analytical form.
Interaction of arrangements of the local spatial management plan in the field of environmental protection with the investment and construction process
Authors: Preweda Edward
Published: February 2019

The local spatial management plan, adopted in Poland at the level of the municipality, is a source of universally binding law, determines the purpose of the area, the distribution of public purpose investments and defines the ways of development and the conditions for land development. The local plan is the basis for issuing the building permit decision on the areas for which its arrangements apply. It directly interferes with the rights vested in entities in real property and property rights. The provisions of the plan, as an act of universally binding law, bind everyone, including all administrative bodies and courts, as well as property owners. When adopting a local spatial management plan, the commune council should be guided by a number of values, including maintaining spatial order, architectural and landscape values, as well as environmental protection requirements. A local plan is an act of local law, therefore it must contain standards defining the specific purpose of each area covered by the regulation in an unambiguous manner, it cannot contain provisions that make land development conditional on subsequent opinions of public administration authorities or allow any entities to individually agree on deviations from the adopted plan. In practice, however, the ambiguity of provisions regarding environmental protection is noticed, in particular in the interpretation of the concept of biologically active land. The work presents how significantly this problem affects the construction investment.
Impact of environmental and climate conditions on the investment potential of real estate in the belt of the Gulf of Gdansk Coast
Authors: Jasińska Elżbieta
Published: February 2019

The subject of this publication is to determine what environmental and climatic factors can significantly affect the value of real estate. As a research object, there was chosen area surrounding the Gulf of Gdansk, which, like the entire coast, is attractive for investment and constitutes an interesting object as a space with a special focus on tourism, including short-term rental. Progressing climate change is particularly affecting this sector. It is safe to assume that unfavorable environmental conditions can significantly change the attractiveness of this area. Therefore, the research hypothesis about the correlation between climate aspects distinguishing the coastal belt and the distribution of real estate prices in the selected area has been verified. The area of the Gulf of Gdansk Coast and the technical and protective belt were analyzed. The weather situation on the coast is different from that prevailing in the rest of the country. There are strong and gusty winds, local floods, but at the same time a natural landscape, proximity to the sea and clean, iodized air. Other possible climatic factors have also been tracked, i.e. temperature, sea level and possible changes that may occur over the next years. The analyzes were based on the data of the KLIMAT project entitled "The impact of climate change on the environment, economy and society", and the Government Project KLIMADA and SPA analyzes. An in-depth analysis of the problem of combining planning documents for the maritime sector influencing the Study of Spatial Development of Polish Marine Areas with Local Spatial Management Plans, introduced Flood Risk Maps and Flood Risk Maps was also conducted.
Ecological risk assessment of chemical contaminants in stormwater sediments
Authors: Sałata Aleksandra , Bąk Łukasz , Górski Jarosław
Published: February 2019

Contaminants bound to suspended solids transported by stormwater pose quantity and quality problems to the water ecosystem. Therefore, it is necessary to carry out an ecological risk assessment. Currently, Polish legal regulations do not require that stormwater sediments should be tested for hazardous substances prior to their removal. Ecological evaluation was performed for polycyclic aromatic hydrocarbons (PAHs) and heavy metals in the sediments from three selected stormwater sedimentation tanks located in urban catchment areas of Kielce city. The purpose this study was to analyze sediments for chemical contaminants and to demonstrate the relationship between contaminant levels and physical attributes of the catchment, including land use, drainage area, age of catchment and impervious surface in the watershed. Levels of PAHs and heavy metals (Cd, Cr, Ni, Pb and Zn) in stormwater sediments were then compared with Polish regulations and ecological screening values to determine their potential risk to environment were established. The results of the current study suggest that stormwater sediments are moderately contaminated with PAHs and heavy metals according to domestic regulations. They are, however, highly contaminated according to ecological benchmarks, which are exceeded several times.
Unit TSP Abatement Costs of Building Modernization as a Tool of Air Quality Management: Krakow Case Study
Authors: Stypka Tomasz , Flaga-Maryańczyk Agnieszka
Published: February 2019

The problem of air quality is an urgent, and widely discussed political issue nowadays. Reducing air emissions is an expensive element of air quality management which can be reached by set of different independent means. One of the areas where solutions for improving air quality in cities can be found is the largest energy-consuming building sector, and related heating needs. The aim of the paper is to estimate the unit Total Suspended Particulates (TSP) abatement costs of building envelope modernization and replacement of heating systems with cleaner ones for buildings in the city of Krakow (Poland). Three, typical for Krakow, types of buildings are analyzed: a single-family house, a pre-war tenement house, and a block of flats. In all the options the base scenario is a coal heated building. The analyzed building’s upgrade includes different combinations of changes of heat source and insulation improvements. For each of the scenarios, the costs as well as the expected effects of unit TSP emission reduction were estimated for the whole city. This approach can support the decision making, planning and financial balancing of the most beneficial activities or estimation of the expected environmental effects.
Preliminary assessment of the wind conditions as a potential for using wind micro-installation to improve air quality in Poland
Authors: Szulc Aleksandra , Tomaszewska Barbara
Published: February 2019

Poland has been struggling with the problem of exceedance of the permissible levels of air pollutions such as particulate matter (PM10, PM2.5) and benzo(a)pyrene (BaP) for several years. In the years 2007-2015 the concentrations of PM10 and BaP exceeded the European Union (EU) limit values. The vast majority of the country is characterised by wind energy zones described as very favorable and favorable. Facing the current legal regulations, wind micro-installations are becoming an opportunity to use the potential of wind energy in Poland. The micro-installations market in Poland is constantly growing. In 2017 there was recorded a nearly ten-fold increase in the number of micro-installations of renewable energy sources connected to the network in regard of 2015. The analysis based on available wind energy resources and available technologies of small wind turbines on the market showed that by installing a 10 kW turbine in the zone with the most favorable wind conditions (1000 kWh/m2/year) one can avoid 93kg of dust emissions to the air and 140 kg of CO and 6222 kg of CO2. The calculated reduction of dust emissions for 3 kW wind turbine in area of Rabka-Zdrój is about 0.8 kg, in the case of BaP 0.0003 kg, and for CO2 47.3 kg.
Analysis of phosphorus migration into soil profiles fertilized with struvite
Authors: Worwąg Małgorzata , Sobik-Szołtysek Jolanta
Published: February 2019

The focus of the present study was on phosphorus migration into soil profile fertilized with struvite with various doses (0.0 g – control, 0.1 g, 0.5 g and 1.0 g). Lysimeter examinations were carried out in 3 columns which modelled 3 levels of soil washing (10, 20 and 30 cm) for each soil mixture with specific struvite doses. Each experiment consisted in flushing water through a column filled with a mixture, with an amount modelling the average annual rainfall for the area of the city of Czestochowa, Poland, adopted at the level of 650 mm. The tests were conducted for 12 days, with simulation of monthly rainfall performed on each day. The phosphorus content was analyzed in the leachate. It was found based on the results that the amount of leached phosphorus was directly connected with the struvite dose in the mixture. The highest phosphorus concentrations were observed at the level of 20 cm of the height of soil profile for the dose of 0.1 g struvite. In the case of the higher struvite doses, i.e. 1.0 g, the highest concentration was found for the height of 30 cm. A decline in concentration of the leached phosphorus was observed after the sixth sampling of the eluate, which resulted from leaching the soil profile with simulated annual rainfall amount.
Simulation of an aircraft radial engine misfire detection
Authors: Grabowski Łukasz , Karpiński Paweł , Pietrykowski Konrad
Published: February 2019

The misfire phenomenon is particularly unfavourable in aircraft engines because it affects the stability and reliability of work. This paper presents the algorithm for detecting ignition failure in a radial aircraft engine. The Crankshaft Velocity Fluctuation method was applied, which consists in analysing changes in the crankshaft speed signal as a function of time. A zero-dimensional model of the aircraft engine was developed in order to perform the research. The validation of the model was performed using the results from the test bench. The model was subjected to simulation tests in fixed operating conditions. Based on the engine speed signal obtained as a result of the simulation, the normalized second derivative of the signal was determined based on the adopted algorithm. On the basis of this derivative, a criterion was defined to assess the occurrence of the misfire phenomenon. The results of the calculations can be compared in future with the results of the real engine tests.