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This paper presents a study regarding the noise reduction of the turbojet engine, in particular the jet noise of a micro turbojet engine. The results of the measurement campaign are presented followed by a performances analysis which is based on the measured data by the test bench. Within the tests, beside the baseline nozzle other two nozzles with chevrons were tested and evaluated. First type of nozzle is foreseen with eight triangular chevrons, the length of the chevrons being L = 10 percentages from the equivalent diameter and an immersion angle of I = 0 deg. For the second nozzle the length and the immersion angle were maintained, only the chevrons number were increased at 16. The micro turbojet engine has been tested at four different regimes of speed. The engine performances were monitored by measuring the fuel flow, the temperature in front of the turbine, the intake air flow, the compression ratio, the propulsion force and the temperature before the compressor. In addition, during the testing, the vibrations were measured on axial and radial direction which indicate a normal functioning of the engine during the chevron nozzles testing. Regarding the noise, it was concluded that at low regimes the noise doesn’t presents any reduction when using the chevron nozzles, while at high regimes an overall noise reduction of 2–3 dB(A) was achieved. Regarding the engine performances, a decrease in the temperature in front of the turbine, compression ratio and the intake air and fuel flow was achieved and also a drop of few percent of the propulsion force.
Grigore Cican; Marius Deaconu; Daniel-Eugeniu Crunteanu. Impact of Using Chevrons Nozzle on the Acoustics and Performances of a Micro Turbojet Engine. Applied Sciences 2021, 11, 5158 .
AMA StyleGrigore Cican, Marius Deaconu, Daniel-Eugeniu Crunteanu. Impact of Using Chevrons Nozzle on the Acoustics and Performances of a Micro Turbojet Engine. Applied Sciences. 2021; 11 (11):5158.
Chicago/Turabian StyleGrigore Cican; Marius Deaconu; Daniel-Eugeniu Crunteanu. 2021. "Impact of Using Chevrons Nozzle on the Acoustics and Performances of a Micro Turbojet Engine." Applied Sciences 11, no. 11: 5158.
The paper is presenting the experimental analysis of the use of biodiesel from waste sunflower oil and a blend of sunflower oil with palm oil as fuel for aviation turbo-engines. A comparative analysis for fuel mixtures made of Jet A + 5% Aeroshell 500 Oil (Ke) with 10%, 30%, and 50% for each bio-fuel type has been performed and Ke has been used as reference. Firstly, the following physical and chemical properties were determined: density, viscosity, flash point, freezing point, calorific power. Then, elemental analysis and Fourier transform infrared spectroscopy (FTIR) analysis were conducted for Ke, biodiesel obtained from recycled sunflower oil (SF), biodiesel obtained from blending recycled sunflower oil, and recycled palm oil (SFP), and for each fuel blend. Secondly, experimental tests of the blends have been conducted on the Jet Cat P80® micro-turbo engine (Gunt Hamburg, Barsbüttel, Germany). The tests have been conducted at different engine working regimes as follows: idle, cruise, intermediate, and maximum. For each regime, a one-minute testing period was chosen, and the engine parameters have been monitored. The turbo engine instrumentation recorded the temperature after the compressor and before the turbine, the fuel consumption and air flow, pressure inside the combustion chamber, and generated thrust. The burning efficiency and the specific consumption have been calculated for all four above-mentioned regimes and for all fuel blends. Two accelerometers have been installed on the engine’s support to register radial and axial vibrations allowing the assessment of engine stability.
Grigore Cican; Marius Deaconu; Radu Mirea; Laurentiu Ceatra; Mihaiella Cretu. An Experimental Investigation to Use the Biodiesel Resulting from Recycled Sunflower Oil, and Sunflower Oil with Palm Oil as Fuels for Aviation Turbo-Engines. International Journal of Environmental Research and Public Health 2021, 18, 5189 .
AMA StyleGrigore Cican, Marius Deaconu, Radu Mirea, Laurentiu Ceatra, Mihaiella Cretu. An Experimental Investigation to Use the Biodiesel Resulting from Recycled Sunflower Oil, and Sunflower Oil with Palm Oil as Fuels for Aviation Turbo-Engines. International Journal of Environmental Research and Public Health. 2021; 18 (10):5189.
Chicago/Turabian StyleGrigore Cican; Marius Deaconu; Radu Mirea; Laurentiu Ceatra; Mihaiella Cretu. 2021. "An Experimental Investigation to Use the Biodiesel Resulting from Recycled Sunflower Oil, and Sunflower Oil with Palm Oil as Fuels for Aviation Turbo-Engines." International Journal of Environmental Research and Public Health 18, no. 10: 5189.
This paper presents the development, construction and testing of a new type of solar–thermal propulsion system which can be used for low earth orbit (LEO) satellites. Currently, the vast majority of LEO satellites are fitted with a cold gas propulsion system. Although such a propulsion system is preferred, the service duration of an LEO satellite is limited by the amount of cold gas they carry onboard. In the case of the new type of solar–thermal propulsion system proposed in this paper, the cold gas is first transferred from the main tank in a cylindrical service tank/buffer tank which is placed in the focal line of a concave mirror. After the gas is heated by the solar light focused on the service tank by the concave mirror, it expands by opening the appropriate solenoid valve for the satellite’s attitude control. In this way the service duration of LEO satellite on orbit can increase by 2.5 times compared with a classic cold gas propulsion system. This is due to the propellant’s internal energy increase by the focused solar light. This paper also presents the results achieved by carrying out tests for the hot gas propulsion system in a controlled environment.
Constantin Sandu; Valentin Silivestru; Grigore Cican; Horațiu Șerbescu; Traian Tipa; Andrei Totu; Andrei Radu. On a New Type of Combined Solar–Thermal/Cold Gas Propulsion System Used for LEO Satellite’s Attitude Control. Applied Sciences 2020, 10, 7197 .
AMA StyleConstantin Sandu, Valentin Silivestru, Grigore Cican, Horațiu Șerbescu, Traian Tipa, Andrei Totu, Andrei Radu. On a New Type of Combined Solar–Thermal/Cold Gas Propulsion System Used for LEO Satellite’s Attitude Control. Applied Sciences. 2020; 10 (20):7197.
Chicago/Turabian StyleConstantin Sandu; Valentin Silivestru; Grigore Cican; Horațiu Șerbescu; Traian Tipa; Andrei Totu; Andrei Radu. 2020. "On a New Type of Combined Solar–Thermal/Cold Gas Propulsion System Used for LEO Satellite’s Attitude Control." Applied Sciences 10, no. 20: 7197.
This paper presents an analysis of the possibility of using recycled pork fat-based biodiesel as fuel for aviation turbo-engines. The analysis consists of the assessment of four blends of Jet A kerosene with 10%, 30%, 50%, and 100% biodiesel and pure Jet A that was used as reference in the study. The first part of the paper presents the physical-chemical properties of the blends: density, viscosity, flash point, freezing point, and calorific power. Through Fourier transform infrared spectroscopy (FTIR) analysis, a benchmark was performed on the mixtures of Jet A with 10%, 20%, 30%, 50%, and 100% biodiesel compared with Jet A. The second part of the paper presents the test results of these blends used for fuelling a Jet Cat P80 turbo engine at the Turbo Engines Laboratory of the Aerospace Engineering Faculty of Polyethnic University of Bucharest. These functional tests were performed using different operating regimes as follows: idle, cruise, intermediate, and maximum. For each regime, a testing period of around 1 min was selected and the engine parameters were monitored during the test execution. The burning efficiency was calculated for the maximum regime for all mixtures. To evaluate the functioning stability of the turbo engine using biodiesel, two accelerometers were mounted on the engine support that recorded the radial and axial vibrations. Moreover, to assess the burning stability and to identify other acoustic spectral components when biodiesel is used, two microphones were placed near the jet region. A comparative analysis between blends was made by taking the Jet A fuel as reference.
Grigore Cican; Marius Deaconu; Radu Mirea; Laurentiu Ceatra; Mihaiella Cretu; Tănase Dobre. Investigating the Use of Recycled Pork Fat-Based Biodiesel in Aviation Turbo Engines. Processes 2020, 8, 1196 .
AMA StyleGrigore Cican, Marius Deaconu, Radu Mirea, Laurentiu Ceatra, Mihaiella Cretu, Tănase Dobre. Investigating the Use of Recycled Pork Fat-Based Biodiesel in Aviation Turbo Engines. Processes. 2020; 8 (9):1196.
Chicago/Turabian StyleGrigore Cican; Marius Deaconu; Radu Mirea; Laurentiu Ceatra; Mihaiella Cretu; Tănase Dobre. 2020. "Investigating the Use of Recycled Pork Fat-Based Biodiesel in Aviation Turbo Engines." Processes 8, no. 9: 1196.
The growth of the urban population and its activity in major cities has led to various public health challenges, including environmental pollution, which are reflected in a decrease in the well-being of societies. This paper presents a predictive tool used to mitigate the noise impact study of commercial centre noise on the surrounding houses, the study being conducted prior to its construction. Before the construction of the supermarket, the sound pressure levels from the façade of the surrounding building are measured to have a background noise level of the analysed area. The noise impact study is made using prediction software in which the houses and the shopping centre buildings are numerically modelled. The main noise sources of the commercial centre, defined in numerical predictions, are represented by the air conditioners, heat pumps situated on the roof and the noise generated by the activities from the supply ramp. The noise impact evaluation is performed at different heights and by determining the number of affected inhabitants. To reduce the number of exposed inhabitants to noise, four technical solutions are presented. The proposed noise solutions are based on technical and economic analyses and also on the urban landscape. The study presents the noise prediction for which the propagation calculus was made according to ISO 9613-2. The noise limits were evaluated according to the Romanian national legislation. The final part of this study presents the noise measurements performed after the construction of this shopping centre and the validation of the implemented noise reduction solution.
Marius Deaconu; Grigore Cican; Laurentiu Cristea. Noise Impact Mitigation of Shopping Centres Located near Densely Populated Areas for a Better Quality of Life. Applied Sciences 2020, 10, 6484 .
AMA StyleMarius Deaconu, Grigore Cican, Laurentiu Cristea. Noise Impact Mitigation of Shopping Centres Located near Densely Populated Areas for a Better Quality of Life. Applied Sciences. 2020; 10 (18):6484.
Chicago/Turabian StyleMarius Deaconu; Grigore Cican; Laurentiu Cristea. 2020. "Noise Impact Mitigation of Shopping Centres Located near Densely Populated Areas for a Better Quality of Life." Applied Sciences 10, no. 18: 6484.
This paper analyzes the performances and the emissions of the JETCAT P80 microengine, when jet A jet A + 10% biodiesel (BD), jet A + 20% biodiesel, and jet A + 30% biodiesel are utilized as fuel, and to each of these combinations is added 5% of Aeroshell Oil 500. The performances will be assessed based on the engine speed, for the generated thrust force, the temperature in front of the turbine, and on the fuel flow. The paper will investigate the performances and the emissions generated by the four fuel blends burning when the engine is idle, at the cruise and at the max regime. This will be realized by maintaining each of these regimes for approximately a minute and a half. During the tests, the vibrations were monitored both radially and axially for the observation of the engine function regimes. From the measurements, the concentrations of SO2, NOx, and CH4 will be analyzed, highlighting the emissions of SO2. There were performed measurements to determine the fuel blend's density in order to transform the values of the fuel flow from liter per hour into kilogram per second. Having these data registered from the engine, a jet engine cycle analysis at max regime will be performed based on the combustion efficiency, the thermal efficiency of the engine, and the specific fuel consumption.
Grigore Cican; Valentin Plesu; Marius Deaconu; Adina Cristina Toma; Mihaiella Cretu. Performances and Emissions Evaluation of a Microturbojet Engine Running on Biodiesel Blends. Journal of Energy Resources Technology 2019, 141, 1 .
AMA StyleGrigore Cican, Valentin Plesu, Marius Deaconu, Adina Cristina Toma, Mihaiella Cretu. Performances and Emissions Evaluation of a Microturbojet Engine Running on Biodiesel Blends. Journal of Energy Resources Technology. 2019; 141 (7):1.
Chicago/Turabian StyleGrigore Cican; Valentin Plesu; Marius Deaconu; Adina Cristina Toma; Mihaiella Cretu. 2019. "Performances and Emissions Evaluation of a Microturbojet Engine Running on Biodiesel Blends." Journal of Energy Resources Technology 141, no. 7: 1.
The microengine was tested to obtain the main functioning parameters and coefficients and to obtain input data for the numerical simulations. A series of tests were performed with the engine at different regimes in the anechoic room without the acoustic reflexions and other sound sources that can influence the results. The test was performed in order to obtain the acoustic propagation in the close and far field of the engine equipped with the baseline nozzle. Transient computational fluid dynamics simulation were made using LES turbulence model for the baseline nozzle of the turbojet. Based on the flow fields resulted from the CFX simulations the acoustic field was computed. The comparative analysis between the experimental measurements and the numerical results highlighted a good agreement for the acoustic directivity and for the sound pressure in close field obtained from both methods. The comparative analysis was made taking into account the FFT (Fast Fourier Transform) spectral component. The obtained results will be used as input data for numerical simulations that uses noise reduction method based on the mechanical chevron solutions.
Grigore Cican; Marius Deaconu; Florin Frunzulica. JetCat P80 noise experimental and numerical evaluation. INTERNATIONAL CONFERENCE OF NUMERICAL ANALYSIS AND APPLIED MATHEMATICS (ICNAAM 2017) 2018, 1978, 370003 .
AMA StyleGrigore Cican, Marius Deaconu, Florin Frunzulica. JetCat P80 noise experimental and numerical evaluation. INTERNATIONAL CONFERENCE OF NUMERICAL ANALYSIS AND APPLIED MATHEMATICS (ICNAAM 2017). 2018; 1978 (1):370003.
Chicago/Turabian StyleGrigore Cican; Marius Deaconu; Florin Frunzulica. 2018. "JetCat P80 noise experimental and numerical evaluation." INTERNATIONAL CONFERENCE OF NUMERICAL ANALYSIS AND APPLIED MATHEMATICS (ICNAAM 2017) 1978, no. 1: 370003.
In this paper, the noise impact of a turbojet testing cell on the adjacent community is investigated. There are scenarios in which the noise from two different turbo engines is analysed. For the noise impact study, acoustic measurements were taken in the test cell to obtain the transmission loss of the three silencers of the test cell. To allow testing of high-power turbojets as Viper or R-11F-300 Tumansky, the test cell was restored and relocated to minimize the noise impact on the surrounding area. The study presents the affected buildings and the number of inhabitants exposed to noise that is assessed according to a German VBEB method based on noise level at façade of the buildings. The study presents the calculus methodologies of the acoustic propagation according ISO 9613-2 on the surrounding area and the noise limits according to the national legislation. To reduce the conflict areas, a technical solution for the intake silencer is proposed.
Marius Deaconu; Grigore Cican. Turbojet Test Cell and Noise Impact Assessment in the Vicinity of Romanian Research and Development Institute for Gas Turbines COMOTI. Acoustics Australia 2018, 1 -9.
AMA StyleMarius Deaconu, Grigore Cican. Turbojet Test Cell and Noise Impact Assessment in the Vicinity of Romanian Research and Development Institute for Gas Turbines COMOTI. Acoustics Australia. 2018; ():1-9.
Chicago/Turabian StyleMarius Deaconu; Grigore Cican. 2018. "Turbojet Test Cell and Noise Impact Assessment in the Vicinity of Romanian Research and Development Institute for Gas Turbines COMOTI." Acoustics Australia , no. : 1-9.
The micro gas turbine propulsion systems represent a good choice for the unmanned aerial vehicles (UAVs). The present work monitors the engine parameters, correlating them with other important engine instrumentation data. The aim of this research was to study the operation of the Jet CAT using various types of fuels under various operating conditions: normal acceleration and sudden acceleration. The measured parameters were monitored under different conditions: (A) Engine operation at two different ambient temperatures – outdoor at 0ºC and inside at 19ºC; and (B) Using 4 fuel types: kerosene, diesel fuel, kerosene with 5% gasoline and kerosene with 10% gasoline. The relevance of this work is given by the fact that a detailed analysis is performed for the idle regime. The paper will present the detailed test plan used and the most relevant charts with the obtained results for: start time, force, temperature before turbine, fuel flow, depending on micro turbo engine speed.
Grigore Cican; Adina Toma; Cristian Puşcaşu; Razvan Catana. Jet CAT P80 Thermal Analyses and Performance Assessment Using Different Fuels Types. Journal of Thermal Science 2018, 27, 389 -393.
AMA StyleGrigore Cican, Adina Toma, Cristian Puşcaşu, Razvan Catana. Jet CAT P80 Thermal Analyses and Performance Assessment Using Different Fuels Types. Journal of Thermal Science. 2018; 27 (4):389-393.
Chicago/Turabian StyleGrigore Cican; Adina Toma; Cristian Puşcaşu; Razvan Catana. 2018. "Jet CAT P80 Thermal Analyses and Performance Assessment Using Different Fuels Types." Journal of Thermal Science 27, no. 4: 389-393.
The purpose of this work is knowing the JetCAT P80 acoustic performances in order to know how to integrate him into the laboratory infrastructure and evaluate his noise impact on staff, students and on the entire campus, such that his exploitation can be performed without interfering with the other university courses. A series of noise measurements at different operating regimes were planned to evaluate and obtain the JetCAT P80 acoustic field. The paper will present inside and outside laboratory room noise measurements, correlated with JetCAT P80 speed in order to assess the staff and students noise exposure. Based on these measurements, the maximum running time will be calculated such as the exposure level to be kept under the legal noise limits. Taking into account the worst scenario (most loud operating regime), measurements results will be used to predict the noise contours in the campus area. The noise contours will be calculated using noise mapping commercial software and will help to schedule the faculty program. The obtained noise results are input for future experimental and numerical simulation work to reduce the jet noise by using different types of noise reduction gas dynamic method.
Grigore Cican; Marius Deaconu; Adina Toma; Adrian Gruzea. Micro Turbo Engine JetCAT P80 Acoustic Evaluation. Springer Proceedings in Physics 2017, 129 -135.
AMA StyleGrigore Cican, Marius Deaconu, Adina Toma, Adrian Gruzea. Micro Turbo Engine JetCAT P80 Acoustic Evaluation. Springer Proceedings in Physics. 2017; ():129-135.
Chicago/Turabian StyleGrigore Cican; Marius Deaconu; Adina Toma; Adrian Gruzea. 2017. "Micro Turbo Engine JetCAT P80 Acoustic Evaluation." Springer Proceedings in Physics , no. : 129-135.