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Manuel Fritsche; Philipp Epple; Boris Kubrak; Stefan Gast; Antonio Delgado; Valentyn Barannik. Numerical Performance Predictions of Artificial Intelligence-Driven Centrifugal Compressor Designs. 2021, 1 .
AMA StyleManuel Fritsche, Philipp Epple, Boris Kubrak, Stefan Gast, Antonio Delgado, Valentyn Barannik. Numerical Performance Predictions of Artificial Intelligence-Driven Centrifugal Compressor Designs. . 2021; ():1.
Chicago/Turabian StyleManuel Fritsche; Philipp Epple; Boris Kubrak; Stefan Gast; Antonio Delgado; Valentyn Barannik. 2021. "Numerical Performance Predictions of Artificial Intelligence-Driven Centrifugal Compressor Designs." , no. : 1.
Manuel Fritsche; Philipp Epple; Antonio Delgado. Analytical and Numerical Investigation of the Fluid Structure Interaction of an Elastic Beam in a Water Channel. 2021, 1 .
AMA StyleManuel Fritsche, Philipp Epple, Antonio Delgado. Analytical and Numerical Investigation of the Fluid Structure Interaction of an Elastic Beam in a Water Channel. . 2021; ():1.
Chicago/Turabian StyleManuel Fritsche; Philipp Epple; Antonio Delgado. 2021. "Analytical and Numerical Investigation of the Fluid Structure Interaction of an Elastic Beam in a Water Channel." , no. : 1.
In this work, the effects of a functionalization method involving different conditions and milling processes on the dispersion and thermal and electrical conductivity of multiwalled carbon nanotubes were studied. The surfaces of MWCNTs were modified using a mixture of sulfuric and nitric acid as an acid treatment and potassium persulfate and sodium hydroxide as an alkaline treatment to achieve more hydrophilic MWCNTs. The morphological and structural investigations were carried out using transmission electron microscopy and Fourier transform infrared spectroscopy. Furthermore, the dispersion characteristics and thermal and electrical conductivity of the as-prepared water-based nanofluids were measured. As a result, the dispersion characteristics revealed that the best dispersion and stability results were obtained for alkaline-treated MWCNTs using potassium persulfate and sodium hydroxide. The thermophysical study using a thermal conductivity analyzer exhibited that the thermal conductivity of the pristine MWCNT nanofluid (0.1 wt%) was enhanced from 603.5 to 610.4 mW/m·K and the electrical conductivity of the raw MWCNT nanofluid was increased from 16.2 to 125.8 μS/cm at 25 °C after alkaline treatment and milling processes, which were performed using planetary ball milling. Regarding the overall results, the milling process and mild alkaline oxidation process are more environmentally friendly, effective, and convenient for the functionalization of CNTs, without requiring any organic solvents or strong acids.
Baasandulam Tserengombo; Hyomin Jeong; Erdenechimeg Dolgor; Antonio Delgado; Sedong Kim. Effects of Functionalization in Different Conditions and Ball Milling on the Dispersion and Thermal and Electrical Conductivity of MWCNTs in Aqueous Solution. Nanomaterials 2021, 11, 1323 .
AMA StyleBaasandulam Tserengombo, Hyomin Jeong, Erdenechimeg Dolgor, Antonio Delgado, Sedong Kim. Effects of Functionalization in Different Conditions and Ball Milling on the Dispersion and Thermal and Electrical Conductivity of MWCNTs in Aqueous Solution. Nanomaterials. 2021; 11 (5):1323.
Chicago/Turabian StyleBaasandulam Tserengombo; Hyomin Jeong; Erdenechimeg Dolgor; Antonio Delgado; Sedong Kim. 2021. "Effects of Functionalization in Different Conditions and Ball Milling on the Dispersion and Thermal and Electrical Conductivity of MWCNTs in Aqueous Solution." Nanomaterials 11, no. 5: 1323.
This study investigates the impacts of dierent airfoil shapes on the 3D augmentation and power production of horizontal axis wind turbines (HAWTs). The aerodynamic eect from changing the leading and trailing edge of the airfoil is the emphasis of the research. Varied power produced from modifying sensitivity on 3D augmentations, caused by revamping airfoil shapes, are shown. The 3D correction law, considering the chord to radius ratio and the blades’ pitch angle in the rotation, is applied to the airfoil lift coecients. The blade element method (BEM) embedded in the software Qblade with modified lift coecients simulates the power productions of three wind turbines from these airfoils. The comparisons of the boundary layer characteristics, sectional forces, and inflow angle of the blade sections are calculated. The k-omega SST turbulence model in OpenFoam visualizes the stall and separation of the blades’ 2D section. The airfoils with a rounded leading edge show a reduced stall and separated flow region. The power production is 2.3 times higher for the airfoil constructed with a more rounded leading edge S809r and two times higher for the airfoil S809gx of the symmetric structure.
Youjin Kim; Galih Bangga; Antonio Delgado. Investigations of HAWT Airfoil Shape Characteristics and 3D Rotational Augmentation Sensitivity Toward the Aerodynamic Performance Improvement. Sustainability 2020, 12, 7597 .
AMA StyleYoujin Kim, Galih Bangga, Antonio Delgado. Investigations of HAWT Airfoil Shape Characteristics and 3D Rotational Augmentation Sensitivity Toward the Aerodynamic Performance Improvement. Sustainability. 2020; 12 (18):7597.
Chicago/Turabian StyleYoujin Kim; Galih Bangga; Antonio Delgado. 2020. "Investigations of HAWT Airfoil Shape Characteristics and 3D Rotational Augmentation Sensitivity Toward the Aerodynamic Performance Improvement." Sustainability 12, no. 18: 7597.
Over the years, solar collecting systems have gained interest in renewable energy. This study investigated improving the efficiency of the working fluid in thermal solar systems by using nanofluids with three concentrations of alumina, 0.1, 0.3, and 0.5 wt%. The UV-vis absorbance, electronic conductivity, and thermal transfer properties of the nanofluids were analyzed, and the thermal changes with exposure to solar radiation in an experimental collector system were measured by pyranometer. The electronic conductivity, thermal conductivity, and UV-vis absorbance increased with the alumina concentration. Moreover, the temperatures of the nanofluids increased more under solar irradiation than that of distilled water. This implies that the alumina nanofluids absorb solar energy more efficiently than water. The findings of this study suggest that the use of both alumina nanofluids and nanoparticles will improve the efficiency of thermal solar power systems.
Youngho Lee; Hyomin Jeong; Ji-Tae Park; Antonio Delgado; Sedong Kim. Experimental Investigation on Evaluation of Thermal Performance of Solar Heating System Using Al2O3 Nanofluid. Applied Sciences 2020, 10, 5521 .
AMA StyleYoungho Lee, Hyomin Jeong, Ji-Tae Park, Antonio Delgado, Sedong Kim. Experimental Investigation on Evaluation of Thermal Performance of Solar Heating System Using Al2O3 Nanofluid. Applied Sciences. 2020; 10 (16):5521.
Chicago/Turabian StyleYoungho Lee; Hyomin Jeong; Ji-Tae Park; Antonio Delgado; Sedong Kim. 2020. "Experimental Investigation on Evaluation of Thermal Performance of Solar Heating System Using Al2O3 Nanofluid." Applied Sciences 10, no. 16: 5521.
Wettability, roughness and surface treatment methods are essential for the majority of practical applications, where liquid–solid surface interactions take place. The present study experimentally investigated the influence of different mechanical surface treatment methods on the static wettability of uncoated and amphiphobic-coated aluminium alloy (AlMg3) samples, specially focusing on the interaction between surface finishing and coating. Five different surfaces were prepared: as-received substrate, polished, sandpapered, fleece-abraded and sandblasted. After characterisation, the samples were spray-coated using an amphiphobic coating. The characterisation of the uncoated and coated samples involved measurements of the roughness parameters and the apparent contact angles of demineralized water and rapeseed oil. The coating was initially characterised regarding its adhesion to the sample and elevated temperature stability. The applied surface treatments resulted in the scattered sample roughness in the range of Sa = 0.3–15.8 µm, water contact angles of θ a p , w = 78°–106° and extremely low oil contact angles. Coating the samples more than doubled the surface roughness to Sa = 13.3–29 µm, whereas the initial surface treatment properties (structure, anisotropy, etc.) were entirely repressed by the coating properties. Coating led the water contact angles to increase to θ a p , w _ c o a t e d = 162°–173° and even more pronounced oil contact angles to increase to θ a p , o _ c o a t e d = 139°–150°, classifying the surfaces as superhydrophobic and oleophobic.
Nataliia Fedorova; Bettina Ottinger; Vojislav Jovicic; Ana Zbogar-Rasic; Antonio Delgado; Sannakaisa Virtanen. Static Wettability of Differently Mechanically Treated and Amphiphobic-Coated Aluminium Surfaces. Materials 2020, 13, 2240 .
AMA StyleNataliia Fedorova, Bettina Ottinger, Vojislav Jovicic, Ana Zbogar-Rasic, Antonio Delgado, Sannakaisa Virtanen. Static Wettability of Differently Mechanically Treated and Amphiphobic-Coated Aluminium Surfaces. Materials. 2020; 13 (10):2240.
Chicago/Turabian StyleNataliia Fedorova; Bettina Ottinger; Vojislav Jovicic; Ana Zbogar-Rasic; Antonio Delgado; Sannakaisa Virtanen. 2020. "Static Wettability of Differently Mechanically Treated and Amphiphobic-Coated Aluminium Surfaces." Materials 13, no. 10: 2240.
The present paper takes up the underlying nonlinear initial value problem from a preceding author’s work about the dynamics of a single bubble in a highly viscous liquid medium under different pressure impacts. The arising ordinary differential equation is mainly based on the constitutive relation of a second-order liquid that in particular includes two non-Newtonian material constants. In this article, the significance of these coefficients is mathematically analyzed in detail by proving the existence of stable solutions of the named initial value problem. This is achieved by special transformations of the differential equation at hand and the introduction of appropriate Lyapunov functions. It particularly turns out that a combined condition of the non-Newtonian coefficients and diverse restrictions to the external pressure impact are decisive for the validity of the existence results. Furthermore, the convergence speed of solutions is investigated by considering the linearized equation associated with the present initial value problem and by applying a special variant of Gronwall’s lemma. The main theoretical result, being the prementioned strong condition for the non-Newtonian coefficients, is finally compared to real data sets.
Alexandre Wolf; Cornelia Rauh; Antonio Delgado. Non-Newtonian coefficient condition for a stable long-time behavior of a single bubble: existence and characteristics of stable solutions. Archive of Applied Mechanics 2020, 90, 1317 -1331.
AMA StyleAlexandre Wolf, Cornelia Rauh, Antonio Delgado. Non-Newtonian coefficient condition for a stable long-time behavior of a single bubble: existence and characteristics of stable solutions. Archive of Applied Mechanics. 2020; 90 (6):1317-1331.
Chicago/Turabian StyleAlexandre Wolf; Cornelia Rauh; Antonio Delgado. 2020. "Non-Newtonian coefficient condition for a stable long-time behavior of a single bubble: existence and characteristics of stable solutions." Archive of Applied Mechanics 90, no. 6: 1317-1331.
Thermal energy of flue gases (FG) dissipating from industrial facilities into the environment, constitute around 20% of the total dissipated thermal energy. Being part of the FG, water vapour carries thermal energy out of the system in the form of the latent heat, which can be recovered by condensation, thus increasing the overall efficiency of an industrial process. The limiting factor in this case is the low dew point temperature (usually 40–60 °C) of the water vapour in the FG. The increase of the dew point temperature can be achieved by increasing the water content or pressure. Taking these measures as a basis, the presented work investigated the following concepts for increasing the dew point temperature: humidification of the flue gas using water, humidification using steam, compression of the FG and usage of the steam ejector. Modelling of these concepts was performed using the commercial software Aspen®. The humidification of the FG using water resulted in the negligible increase in the dew point (3 °C). Using steam humidification the temperatures of up to 92 °C were reached, while the use of steam ejector led to few degrees higher dew point temperatures. However, both concepts proved to be energy demanding, due to the energy requirements for the steam generation. The FG compression enabled the achievement of a 97 °C dew point temperature, being both energy-efficient and exhibiting the lowest energy cost.
Nataliia Fedorova; Pegah Aziziyanesfahani; Vojislav Jovicic; Ana Zbogar-Rasic; Muhammad Jehanzaib Khan; Antonio Delgado. Investigation of the Concepts to Increase the Dew Point Temperature for Thermal Energy Recovery from Flue Gas, Using Aspen®. Energies 2019, 12, 1585 .
AMA StyleNataliia Fedorova, Pegah Aziziyanesfahani, Vojislav Jovicic, Ana Zbogar-Rasic, Muhammad Jehanzaib Khan, Antonio Delgado. Investigation of the Concepts to Increase the Dew Point Temperature for Thermal Energy Recovery from Flue Gas, Using Aspen®. Energies. 2019; 12 (9):1585.
Chicago/Turabian StyleNataliia Fedorova; Pegah Aziziyanesfahani; Vojislav Jovicic; Ana Zbogar-Rasic; Muhammad Jehanzaib Khan; Antonio Delgado. 2019. "Investigation of the Concepts to Increase the Dew Point Temperature for Thermal Energy Recovery from Flue Gas, Using Aspen®." Energies 12, no. 9: 1585.
Perfluorinated compounds (PFCs) are manmade chemicals, containing the covalent C-F bond, which is among the strongest chemical bonds known to organic chemistry. Abundant use of these chemicals contaminates air, water, and soil around the world. Despite recent initiatives and legal regulations set to reduce their omnipresence, conventional water purification processes are either inefficient or very expensive, especially for low PFC contamination levels. This research is focused on the non-thermal atmospheric plasma (NTAP) decomposition of very low concentrations (<1 µg/L) of PFCs (especially perfluorooctanoic acid (PFOA) and perfluorooctanesulfonate (PFOS)), present in the wastewater produced during the process of PFCs removal from contaminated soil. The efficiency of the decomposition process was investigated for air, oxygen, and nitrogen plasma, with exposure times of 1–10 min and different plasma nozzle- and reactor sizes. Experiments demonstrated that the NTAP treatment is an efficient alternative method for degradation of more than 50% of the initial PFC concentration in the water samples, in less than 200 s. The final concentration of PFC showed strong dependency on the tested parameters. The treatment effect showed to be strongly non-linear with time, followed by the reduction of the pH-value of the treated sample, which might present a limiting factor for further PFC decomposition.
Vojislav Jovicic; Muhammad Jehanzaib Khan; Ana Zbogar-Rasic; Nataliia Fedorova; Alexander Poser; Peter Swoboda; Antonio Delgado. Degradation of Low Concentrated Perfluorinated Compounds (PFCs) from Water Samples Using Non-Thermal Atmospheric Plasma (NTAP). Energies 2018, 11, 1290 .
AMA StyleVojislav Jovicic, Muhammad Jehanzaib Khan, Ana Zbogar-Rasic, Nataliia Fedorova, Alexander Poser, Peter Swoboda, Antonio Delgado. Degradation of Low Concentrated Perfluorinated Compounds (PFCs) from Water Samples Using Non-Thermal Atmospheric Plasma (NTAP). Energies. 2018; 11 (5):1290.
Chicago/Turabian StyleVojislav Jovicic; Muhammad Jehanzaib Khan; Ana Zbogar-Rasic; Nataliia Fedorova; Alexander Poser; Peter Swoboda; Antonio Delgado. 2018. "Degradation of Low Concentrated Perfluorinated Compounds (PFCs) from Water Samples Using Non-Thermal Atmospheric Plasma (NTAP)." Energies 11, no. 5: 1290.
High power light emitting diodes (LEDs) being used for low and high beam in automotive lighting need active cooling of their heat sinks by radial or axial fans. But the moving elements of the fan cause abrasion, noise, and high energy consumption. Synthetic jets can replace conventional fans with their disadvantages and allow the directed cooling of LEDs. Therefore, in this paper, flow and heat transfer characteristics of impinging synthetic jets are investigated numerically and experimentally as an alternative to cooling LEDs with fans. It is shown that the impact plate brings forward the laminar-turbulent transition of the jets temporally and spatially. The impact plate itself should not be positioned in the region of the free jet's transition height. Increasing the frequency of the synthetic jet has a greater influence on the heat transfer compared to an increase in amplitude. The maximum cooling performance is achieved for all jet configurations with moderate distances between the orifice and the impact plate. In this case, the jet reaches its highest mass flow and impulse and its lowest temperature.
Robert Glowienko; Hans Derlien; Oezguer Ertunc; Antonio Delgado; Ozgur Ertunc. Numerical and Experimental Analysis of Impinging Synthetic Jets for Cooling a Point-Like Heat Source. Journal of Heat Transfer 2018, 140, 052201 .
AMA StyleRobert Glowienko, Hans Derlien, Oezguer Ertunc, Antonio Delgado, Ozgur Ertunc. Numerical and Experimental Analysis of Impinging Synthetic Jets for Cooling a Point-Like Heat Source. Journal of Heat Transfer. 2018; 140 (5):052201.
Chicago/Turabian StyleRobert Glowienko; Hans Derlien; Oezguer Ertunc; Antonio Delgado; Ozgur Ertunc. 2018. "Numerical and Experimental Analysis of Impinging Synthetic Jets for Cooling a Point-Like Heat Source." Journal of Heat Transfer 140, no. 5: 052201.
In this work, the physical behavior of a small, spherical bubble in a highly viscous, incompressible liquid phase is analyzed under specific pressure impacts. This represents an attractive topic in the food industry, since it is of interest to know under which conditions this two-phase dispersion exhibits a stable state. The specific material law of a second-order liquid, which includes Newtonian and non-Newtonian material constants, provides a nonlinear initial value problem for the radius of the bubble. This system is solved numerically by an efficient version of the classical Runge–Kutta method. By parameter variation, the impact of the dimensionless quantities associated with inertia, non-Newtonian material coefficients, pressure, surface tension and viscosity on the two-phase system is investigated. This particularly yields insights into the stability behavior of the bubble surface. The solution curves show various characteristics such as asymptotic oscillations or monotonically decreasing profiles. These results are transferred to a specific non-Newtonian and Newtonian substance. Finally, by studying stationary solutions, it becomes obvious that only the excitation pressure and the surface tension determine the new equilibrium state of the bubble, which in particular represents its long-time behavior. Furthermore, a sinusoidal driving pressure is used to investigate unstable solutions. The aim of the paper was to bring together these mathematical stability results to practice-oriented considerations.
Alexandre Wolf; Cornelia Rauh; Antonio Delgado. Dynamics and long-time behavior of a small bubble in viscous liquids with applications to food rheology. Archive of Applied Mechanics 2015, 86, 979 -1002.
AMA StyleAlexandre Wolf, Cornelia Rauh, Antonio Delgado. Dynamics and long-time behavior of a small bubble in viscous liquids with applications to food rheology. Archive of Applied Mechanics. 2015; 86 (6):979-1002.
Chicago/Turabian StyleAlexandre Wolf; Cornelia Rauh; Antonio Delgado. 2015. "Dynamics and long-time behavior of a small bubble in viscous liquids with applications to food rheology." Archive of Applied Mechanics 86, no. 6: 979-1002.
Over the last few decades the food and beverage industry has become increasingly aware of its energy and water usage. Customers are demanding an increasing level of sustainability. This is especially true within the brewery industry. The process of brewing itself is a demanding process, with respect to both energy and water requirements. To increase the knowledge about the holistic process chains, e.g. for decision making and for testing operational and procedural setups there is an evolving need for virtualisation. This paper focuses on modelling and simulation of parts within the process of brewing. The shown approach utilises reference nets as a flow-chart-like modelling environment. Models based on the Java programming language are implemented, dealing with stochastic and deterministic events. Results of eight different brew types are shown and a complete schedule with a total of 230 batches, portraying almost a year of production is being simulated.
Stefan Hubert; Thorben Helmers; Frauke Groß; Antonio Delgado. Data driven stochastic modelling and simulation of cooling demand within breweries. Journal of Food Engineering 2015, 176, 97 -109.
AMA StyleStefan Hubert, Thorben Helmers, Frauke Groß, Antonio Delgado. Data driven stochastic modelling and simulation of cooling demand within breweries. Journal of Food Engineering. 2015; 176 ():97-109.
Chicago/Turabian StyleStefan Hubert; Thorben Helmers; Frauke Groß; Antonio Delgado. 2015. "Data driven stochastic modelling and simulation of cooling demand within breweries." Journal of Food Engineering 176, no. : 97-109.
A. Delgado; M. D. Eisner. Schäume - Herstellung, Charakterisierung und Anwendung. Chemie Ingenieur Technik 2014, 86, 1595 -1595.
AMA StyleA. Delgado, M. D. Eisner. Schäume - Herstellung, Charakterisierung und Anwendung. Chemie Ingenieur Technik. 2014; 86 (9):1595-1595.
Chicago/Turabian StyleA. Delgado; M. D. Eisner. 2014. "Schäume - Herstellung, Charakterisierung und Anwendung." Chemie Ingenieur Technik 86, no. 9: 1595-1595.