Daniele Marano - Academia.edu (original) (raw)
Papers by Daniele Marano
Aerospace
The tiltrotor wing structure is one of the most critical and heavily investigated structures in d... more The tiltrotor wing structure is one of the most critical and heavily investigated structures in design due to the fundamental need to consider the interactions between the wing, pylon, and rotor systems to achieve aircraft aeroelastic stability. Indeed, in high-speed forward flight, wing flexural and torsional stiffness have fundamental roles in pitch-whirl stability. Another specific concern of tiltrotors is dynamic mode placement; it is necessary to properly place wing bending modes away from prop-rotor forcing frequencies. The main aeroelastic stability and dynamics requirements and the wing design process flow for the next generation civil tiltrotor are presented in this work. In this context, the use of composite materials plays a fundamental role in the attempt to satisfy the requirements, with the perpetual aim of minimizing the structural weight. An overview of the idealized and adopted models for strength, aeroelasticity, and whirl flutter analysis is provided. The primary ...
The T-WING project is a Clean Sky 2 research project aimed at designing, manufacturing, qualifyin... more The T-WING project is a Clean Sky 2 research project aimed at designing, manufacturing, qualifying and flight testing the new wing of the Next-Generation Civil Tiltrotor Technology Demonstrator (NGCTR-TD. Requirements, design strategy, methodology and main steps followed to achieve the composite wing design are presented. The main driving requirements have been expressed in terms of structural, dynamic, aeroelastic and functional requirements and wing preliminary loads. Based on the above-mentioned requirements, the first design loop is performed by targeting an optimal wing structure able to withstand preliminary design loads, and simultaneously with stiffness and inertia distributions leading to a configuration free from flutter within the flight envelope. The outcome from the first design loop is then used to build a global FEM, to be used for a multi-objective optimization performed in ALTAIR OptiStruct environment.
Aerospace, 2021
The main objective of this paper is to describe a methodology to be applied in the preliminary de... more The main objective of this paper is to describe a methodology to be applied in the preliminary design of a tiltrotor wing based on previously developed conceptual design methods. The reference vehicle is the Next-Generation Civil Tiltrotor Technology Demonstrator (NGCTR-TD) developed by Leonardo Helicopters within the Clean Sky research program framework. In a previous work by the authors, based on the specific requirements (i.e., dynamics, strength, buckling, functional), the first iteration of design was aimed at finding a wing structure with a minimized structural weight but at the same time strong and stiff enough to comply with sizing loads and aeroelastic stability in the flight envelope. Now, the outcome from the first design loop is used to build a global Finite Element Model (FEM), to be used for a multi-objective optimization performed by using a commercial software environment. In other words, the design strategy, aimed at finding a first optimal solution in terms of the ...
Aerotecnica Missili & Spazio, 2021
Pressure load measurements in operative conditions represent a fundamental parameter for improvin... more Pressure load measurements in operative conditions represent a fundamental parameter for improving the knowledge of the in-flight forcing generation and transmission. Furthermore, it is a fundamental step for assessing the validity and confidence of numerical methods able to predict such pressure loads, usually generated by propulsion and turbulent boundary layer. The experimental in-flight measurements and analysis and the correlation with the numerical methods are activities required as a starting point for studying the transmission mechanism through the fuselage which is responsible for the vibration and noise level which can be measured inside and for identifying potential solutions for their mitigation. The in-flight measurements have been carried out on a Leonardo Helicopter tiltrotor with the main goals to perform the validation of an experimental setup in a fully new environment and the assessment of a data analysis procedure according to the objectives of the Clean Sky 2 Fa...
Applied Acoustics, 2020
Polymeric sound absorbers can be produced through electrospinning, a process which allows to fabr... more Polymeric sound absorbers can be produced through electrospinning, a process which allows to fabricate high specific surface materials with a fiber diameter from few nanometers to several micrometers. In this study, a numerical simulation model of the acoustic behavior of poly vinyl pyrrolidone/silica composites were developed. First, the characteristics of the poly vinyl pyrrolidone/silica composites were examined, and the manufacturing of the material were described. Subsequently, the results of the measurements of the sound absorption coefficient were analyzed. Finally, the results of the numerical modeling of the acoustic coefficient were reported. The neural network-based model showed high Pearson correlation coefficient values (0.942), indicating many correct predictions. Taking into account the bell shaped acoustic response of the studied blankets as a function of frequency, the possibility to foresee the needed mass with the neural network-based model will be of great value for the applications where high acoustic absorption is required in specific limited frequency ranges.
International Journal of Aeronautical and Space Sciences, 2020
The T-WING project is a Clean Sky 2 research project aimed at designing, manufacturing, qualifyin... more The T-WING project is a Clean Sky 2 research project aimed at designing, manufacturing, qualifying and flight-testing the new wing of the Next-Generation Civil Tiltrotor Technology Demonstrator (NGCTR-TD), as part of the Fast Rotorcraft Innovative Aircraft Demonstrator Platforms (FRC IADP) activities. Requirements, design strategy, methodology and main steps followed to achieve the composite wing preliminary design are presented. The main driving requirements have been expressed in terms of dynamic requirements (e.g., limitations on natural frequencies), aeroelastic requirements, i.e., compliance with European Aviation Safety Agency (EASA) CS-25 and CS-29 Airworthiness Requirements), structural requirements (e.g., target wing structural mass), functional requirements (e.g., fuel tanks, accessibility, assembly and integration, etc.) and wing preliminary loads. Based on the above-mentioned requirements, the first design loop is performed by targeting an optimal wing structure able to withstand preliminary design loads, and simultaneously with stiffness and inertia distributions leading to a configuration free from flutter within the flight envelope. The outcome from the first design loop is then used to refine the model and compute more reliable flight loads and repeat aeroelastic analysis, returning further requirements to be fulfilled in terms of wing stiffness and inertia distributions. The process is iterated till the fulfillment of all the project requirements.
Aerospace
The tiltrotor wing structure is one of the most critical and heavily investigated structures in d... more The tiltrotor wing structure is one of the most critical and heavily investigated structures in design due to the fundamental need to consider the interactions between the wing, pylon, and rotor systems to achieve aircraft aeroelastic stability. Indeed, in high-speed forward flight, wing flexural and torsional stiffness have fundamental roles in pitch-whirl stability. Another specific concern of tiltrotors is dynamic mode placement; it is necessary to properly place wing bending modes away from prop-rotor forcing frequencies. The main aeroelastic stability and dynamics requirements and the wing design process flow for the next generation civil tiltrotor are presented in this work. In this context, the use of composite materials plays a fundamental role in the attempt to satisfy the requirements, with the perpetual aim of minimizing the structural weight. An overview of the idealized and adopted models for strength, aeroelasticity, and whirl flutter analysis is provided. The primary ...
The T-WING project is a Clean Sky 2 research project aimed at designing, manufacturing, qualifyin... more The T-WING project is a Clean Sky 2 research project aimed at designing, manufacturing, qualifying and flight testing the new wing of the Next-Generation Civil Tiltrotor Technology Demonstrator (NGCTR-TD. Requirements, design strategy, methodology and main steps followed to achieve the composite wing design are presented. The main driving requirements have been expressed in terms of structural, dynamic, aeroelastic and functional requirements and wing preliminary loads. Based on the above-mentioned requirements, the first design loop is performed by targeting an optimal wing structure able to withstand preliminary design loads, and simultaneously with stiffness and inertia distributions leading to a configuration free from flutter within the flight envelope. The outcome from the first design loop is then used to build a global FEM, to be used for a multi-objective optimization performed in ALTAIR OptiStruct environment.
Aerospace, 2021
The main objective of this paper is to describe a methodology to be applied in the preliminary de... more The main objective of this paper is to describe a methodology to be applied in the preliminary design of a tiltrotor wing based on previously developed conceptual design methods. The reference vehicle is the Next-Generation Civil Tiltrotor Technology Demonstrator (NGCTR-TD) developed by Leonardo Helicopters within the Clean Sky research program framework. In a previous work by the authors, based on the specific requirements (i.e., dynamics, strength, buckling, functional), the first iteration of design was aimed at finding a wing structure with a minimized structural weight but at the same time strong and stiff enough to comply with sizing loads and aeroelastic stability in the flight envelope. Now, the outcome from the first design loop is used to build a global Finite Element Model (FEM), to be used for a multi-objective optimization performed by using a commercial software environment. In other words, the design strategy, aimed at finding a first optimal solution in terms of the ...
Aerotecnica Missili & Spazio, 2021
Pressure load measurements in operative conditions represent a fundamental parameter for improvin... more Pressure load measurements in operative conditions represent a fundamental parameter for improving the knowledge of the in-flight forcing generation and transmission. Furthermore, it is a fundamental step for assessing the validity and confidence of numerical methods able to predict such pressure loads, usually generated by propulsion and turbulent boundary layer. The experimental in-flight measurements and analysis and the correlation with the numerical methods are activities required as a starting point for studying the transmission mechanism through the fuselage which is responsible for the vibration and noise level which can be measured inside and for identifying potential solutions for their mitigation. The in-flight measurements have been carried out on a Leonardo Helicopter tiltrotor with the main goals to perform the validation of an experimental setup in a fully new environment and the assessment of a data analysis procedure according to the objectives of the Clean Sky 2 Fa...
Applied Acoustics, 2020
Polymeric sound absorbers can be produced through electrospinning, a process which allows to fabr... more Polymeric sound absorbers can be produced through electrospinning, a process which allows to fabricate high specific surface materials with a fiber diameter from few nanometers to several micrometers. In this study, a numerical simulation model of the acoustic behavior of poly vinyl pyrrolidone/silica composites were developed. First, the characteristics of the poly vinyl pyrrolidone/silica composites were examined, and the manufacturing of the material were described. Subsequently, the results of the measurements of the sound absorption coefficient were analyzed. Finally, the results of the numerical modeling of the acoustic coefficient were reported. The neural network-based model showed high Pearson correlation coefficient values (0.942), indicating many correct predictions. Taking into account the bell shaped acoustic response of the studied blankets as a function of frequency, the possibility to foresee the needed mass with the neural network-based model will be of great value for the applications where high acoustic absorption is required in specific limited frequency ranges.
International Journal of Aeronautical and Space Sciences, 2020
The T-WING project is a Clean Sky 2 research project aimed at designing, manufacturing, qualifyin... more The T-WING project is a Clean Sky 2 research project aimed at designing, manufacturing, qualifying and flight-testing the new wing of the Next-Generation Civil Tiltrotor Technology Demonstrator (NGCTR-TD), as part of the Fast Rotorcraft Innovative Aircraft Demonstrator Platforms (FRC IADP) activities. Requirements, design strategy, methodology and main steps followed to achieve the composite wing preliminary design are presented. The main driving requirements have been expressed in terms of dynamic requirements (e.g., limitations on natural frequencies), aeroelastic requirements, i.e., compliance with European Aviation Safety Agency (EASA) CS-25 and CS-29 Airworthiness Requirements), structural requirements (e.g., target wing structural mass), functional requirements (e.g., fuel tanks, accessibility, assembly and integration, etc.) and wing preliminary loads. Based on the above-mentioned requirements, the first design loop is performed by targeting an optimal wing structure able to withstand preliminary design loads, and simultaneously with stiffness and inertia distributions leading to a configuration free from flutter within the flight envelope. The outcome from the first design loop is then used to refine the model and compute more reliable flight loads and repeat aeroelastic analysis, returning further requirements to be fulfilled in terms of wing stiffness and inertia distributions. The process is iterated till the fulfillment of all the project requirements.