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Risorsa bibliografica obbligatoria
Risorsa bibliografica facoltativa
Scheda Riassuntiva
Anno Accademico 2019/2020
Scuola Scuola di Ingegneria Industriale e dell'Informazione
Insegnamento 097488 - ROTORCRAFT DESIGN
Docente Lanz Massimiliano
Cfu 8.00 Tipo insegnamento Monodisciplinare

Corso di Studi Codice Piano di Studio preventivamente approvato Da (compreso) A (escluso) Insegnamento
Ing Ind - Inf (Mag.)(ord. 270) - BV (469) AERONAUTICAL ENGINEERING - INGEGNERIA AERONAUTICA*AZZZZ097488 - ROTORCRAFT DESIGN

Obiettivi dell'insegnamento

Main goal is to introduce major problems related to preliminary design of a vertical take off aircraft with particular attention to main rotor.


Risultati di apprendimento attesi

Students will be able to evaluate the effect of a change in the main design parameters of a rotor on performance, aeroelastic and aeromechanical stability, flight qualities, vibrations, etc , during the preliminary design pahse of a rotorcraft.


Argomenti trattati

Introduction - Historical background. Classification of vertical take-off vehicles. Helicopter. Hub types: articulated, hingeless and bearingless.

Rotor aerodynamics - Momentum theory in axial flow. Induced power. Blade element theory in axial flight. Figure of merit. Optimal rotor in hovering. Ground effect. Vertical drag. Rotor reference systems. Forces and power in forward flight.

Rigid blade dynamics - Equation of motion of a rigid flapping blade in vacuum. Contribution of aerodynamic forces. Lock number. Floquet theorem. Pitch-flap coupling. Lag and pitch equations of motion. Pitch-flap and flap-lag instabilities. Aeromechanical instabilities.

Performances - Helicopter equations in forward flight. Power required energetic and equilibrium methods. Autorotation. Height-velocity diagram.

Stability and control - Linear equations of motion. Helicopter response to speed, angle of attck and pitch velocity perturbations. Stick fixed longitudinal stability. Automatic stabilization: requirement on control power, sensitivity and damping.

Flexible blade - Equilibrium equations of a rotating blade. Numerical methods for computing rotating frequencies and modes. Dynamic response of a blade. Displacement ans acceleration modes.

Vibrations - Human sensitivity to vibrations. Transmissibility of forces and moments through rotor hub. Passive and active methods for vibration reduction.


Prerequisiti

Basic knowledge in aerodynamics (lifting line theory) and dynamics (frequency response of a single degree of freedom system) are required.


Modalità di valutazione

Assessment of the preparation is based both on the reports of the homework activities and on the oral exam, aimed to verify the knowledge of the arguments presented during lessons.

In particular: 

- ability of critical judgement of the results

- way of presentation of design results in a technical report 

- knowledgle of the assumptions and of the bounds of the numerical methods used

will be considered in final evaluation.


Bibliografia
Risorsa bibliografica obbligatoriaW.Johnson, Rotorcratft Aeromechanics, Editore: Cambridge University Press
Risorsa bibliografica facoltativaA.R.S. Bramwell, Helicopter Dynamics, Editore: Edward Arnold
Risorsa bibliografica facoltativaR.L.Bielawa, Rotary Wing Structural Dynamics and Aeroelasticity, Editore: AIAA Education Series
Risorsa bibliografica facoltativaS.Newmann, The foundations of Helicopter Flight, Editore: Edward Arnold
Risorsa bibliografica obbligatoriaCopy of slides Beep

Forme didattiche
Tipo Forma Didattica Ore di attività svolte in aula
(hh:mm)
Ore di studio autonome
(hh:mm)
Lezione
52:00
78:00
Esercitazione
28:00
42:00
Laboratorio Informatico
0:00
0:00
Laboratorio Sperimentale
0:00
0:00
Laboratorio Di Progetto
0:00
0:00
Totale 80:00 120:00

Informazioni in lingua inglese a supporto dell'internazionalizzazione
Insegnamento erogato in lingua Inglese
Disponibilità di materiale didattico/slides in lingua inglese
Disponibilità di libri di testo/bibliografia in lingua inglese
Possibilità di sostenere l'esame in lingua inglese
schedaincarico v. 1.6.1 / 1.6.1
Area Servizi ICT
26/01/2020