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public:modeles:rotor_68:accueil [2022/09/16 10:05] – supprimée - modification externe (Unknown date) 127.0.0.1 | public:modeles:rotor_68:accueil [2023/04/14 12:36] (Version actuelle) – [Fréquences propres] solenekojtych | ||
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+ | ====== Rotor 68 ====== | ||
+ | |||
+ | < | ||
+ | * [[# | ||
+ | * [[# | ||
+ | <pane id=" | ||
+ | |||
+ | <btn type=" | ||
+ | <modal id=" | ||
+ | **[[https:// | ||
+ | </ | ||
+ | ===== About ===== | ||
+ | |||
+ | To reduce fan noise, an advanced, two-stage, high-pressure-ratio fan having widely spaced blade rows was build and tested. Rotor 68 is the rotor of the second stage of this fan. But, the overall efficiency of this two-stage fan was approximately 5 percentage points less than its design value. Analysis of the test results indicated that the first-stage stator and the second stage had potential for good performance but were hampered mainly by the dampered first-stage rotor. The dampers were responsible for large radial gradients of total pressure and deviation angle across a large portion of the blade height, resulting in mismatches in later blade rows. To improve performance of the first stage as well as the stage matching, the original two-stage fan was reconfigured with a newly designed first-stage rotor. Lower-aspect-ratio blading was selected for the rotor to eliminate both the need for part span dampers and their associated penalties on aerodynamic performance. | ||
+ | |||
+ | * Original technical report [(cite: | ||
+ | author | ||
+ | year = {1979}, | ||
+ | institution | ||
+ | title = {Performance of two-stage fan having low-aspect-ratio first-stage rotor blading}, | ||
+ | number | ||
+ | url = {https:// | ||
+ | } | ||
+ | </ | ||
+ | |||
+ | * Picture : | ||
+ | {{ : | ||
+ | < | ||
+ | |||
+ | <callout type=" | ||
+ | * [[https:// | ||
+ | * {{ : | ||
+ | * {{ : | ||
+ | </ | ||
+ | |||
+ | ===== Reference blade ===== | ||
+ | |||
+ | The **reference blade** is defined with multiple-circular arc profiles[(cite: | ||
+ | |||
+ | ==== Geometry ==== | ||
+ | |||
+ | The geometry of rotor 68 is described in the [[https:// | ||
+ | {{ : | ||
+ | |||
+ | ==== Aerodynamic design | ||
+ | |||
+ | ^ ^ units ^ values | ||
+ | ^ pressure ratio | [-] | 1.54 | | ||
+ | ^ mass flow | ||
+ | ^ tip speed | ||
+ | ^ tip solidity | ||
+ | ^ aspect ratio | [-] | 1.89 | | ||
+ | ^ number of blades | ||
+ | ^ rotative speed | [rad/ | ||
+ | |||
+ | ==== Material properties | ||
+ | |||
+ | The original material of the rotor 68 is not defined in the NASA report. A generic titanium Ti-6Al-4V is considered: | ||
+ | |||
+ | ^ | ||
+ | ^ alloy | [-] | Ti-6Al-4V | ||
+ | ^ Young' | ||
+ | ^ density | ||
+ | ^ Poisson' | ||
+ | ^ yield stress | ||
+ | |||
+ | |||
+ | ==== CAD model ==== | ||
+ | |||
+ | The CAD model is computed with the open source code OpenMCAD[(cite: | ||
+ | |||
+ | < | ||
+ | <col md=" | ||
+ | </ | ||
+ | <col md=" | ||
+ | {{ : | ||
+ | < | ||
+ | </ | ||
+ | <col md=" | ||
+ | {{ : | ||
+ | < | ||
+ | </ | ||
+ | <col md=" | ||
+ | </ | ||
+ | </ | ||
+ | |||
+ | |||
+ | ==== Natural frequencies ==== | ||
+ | |||
+ | |||
+ | First three natural frequencies (with clamped root) for the mesh computed with OpenMCAD[(cite: | ||
+ | |||
+ | ^ Mode ^ Type ^ Natural angular frequency (rad/ | ||
+ | | 1 | 1B | 2492.51 | ||
+ | | 2 | 2B | 7697.97 | ||
+ | | 3 | 1T | 10374.29 | ||
+ | |||
+ | |||
+ | |||
+ | ===== Initial blade ===== | ||
+ | |||
+ | The **initial blade** is defined with in-house LAVA parameters[(cite: | ||
+ | |||
+ | |||
+ | |||
+ | |||
+ | ==== Natural frequencies ==== | ||
+ | |||
+ | First three natural frequencies (with clamped root) | ||
+ | |||
+ | * from the whole mesh: | ||
+ | |||
+ | ^ Mode ^ Type ^ Natural angular frequency (rad/ | ||
+ | | 1 | 1B | 2450.71 | ||
+ | | 2 | 2B | 7608.18 | ||
+ | | 3 | 1T | 10308.76 | ||
+ | |||
+ | |||
+ | * from the reduced order model: | ||
+ | |||
+ | ^ Mode ^ Type ^ Natural angular frequency (rad/ | ||
+ | | 1 | 1B | 2450.84 | ||
+ | | 2 | 2B | 7611.45 | ||
+ | | 3 | 1T | 10314.29 | ||
+ | |||
+ | |||
+ | |||
+ | </ | ||
+ | |||
+ | <pane id=" | ||
+ | |||
+ | <btn type=" | ||
+ | <modal id=" | ||
+ | **[[https:// | ||
+ | </ | ||
+ | |||
+ | ===== À propos ===== | ||
+ | |||
+ | Pour réduire le bruit des soufflantes, | ||
+ | |||
+ | * Rapport technique original [(cite: | ||
+ | author | ||
+ | year = {1979}, | ||
+ | institution | ||
+ | title = {Performance of two-stage fan having low-aspect-ratio first-stage rotor blading}, | ||
+ | number | ||
+ | url = {https:// | ||
+ | } | ||
+ | </ | ||
+ | |||
+ | * Photographie : | ||
+ | {{ : | ||
+ | < | ||
+ | |||
+ | <callout type=" | ||
+ | * [[https:// | ||
+ | * {{ : | ||
+ | * {{ : | ||
+ | </ | ||
+ | |||
+ | ===== Aube de référence ===== | ||
+ | |||
+ | L' | ||
+ | |||
+ | ==== Géométrie ==== | ||
+ | |||
+ | La géométrie du rotor 68 est décrite dans le [[https:// | ||
+ | |||
+ | {{ : | ||
+ | |||
+ | ==== Caractéristiques aérodynamiques | ||
+ | ^ ^ unités | ||
+ | ^ taux de compression | ||
+ | ^ débit massique | ||
+ | ^ vitesse en tête | [m/s] | 427 | | ||
+ | ^ solidité en tête | ||
+ | ^ allongement | ||
+ | ^ nombre d' | ||
+ | ^ vitesse de rotation | ||
+ | |||
+ | ==== Propriétés matériau | ||
+ | |||
+ | Le matériau original du rotor 68 n'est pas défini dans le rapport de la NASA. Un alliage de titane Ti-6Al-4v est considéré : | ||
+ | |||
+ | |||
+ | ^ | ||
+ | ^ alliage | ||
+ | ^ module d' | ||
+ | ^ masse volumique | ||
+ | ^ coefficient de Poisson | ||
+ | ^ limite élastique | ||
+ | |||
+ | ==== Modèle CAO ==== | ||
+ | |||
+ | Le modèle CAO est obtenu avec OpenMCAD[(cite: | ||
+ | |||
+ | < | ||
+ | <col md=" | ||
+ | </ | ||
+ | <col md=" | ||
+ | {{ : | ||
+ | < | ||
+ | </ | ||
+ | <col md=" | ||
+ | {{ : | ||
+ | < | ||
+ | </ | ||
+ | <col md=" | ||
+ | </ | ||
+ | </ | ||
+ | |||
+ | ==== Fréquences propres ==== | ||
+ | |||
+ | Fréquences des trois premiers modes (noeuds du pied d'aube encastrés) pour le maillage obtenu avec OpenMCAD[(cite: | ||
+ | |||
+ | ^ Mode ^ Type ^ Pulsation propre (rad/ | ||
+ | | 1 | 1F | 2492, | ||
+ | | 2 | 2F | 7697, | ||
+ | | 3 | 1T | 10374, | ||
+ | |||
+ | |||
+ | ===== Aube initiale ===== | ||
+ | |||
+ | L' | ||
+ | |||
+ | |||
+ | ==== Fréquences propres ==== | ||
+ | Fréquences des trois premiers modes (noeuds du pied d'aube encastrés), | ||
+ | |||
+ | * pour le maillage complet : | ||
+ | |||
+ | ^ Mode ^ Type ^ Pulsation propre (rad/ | ||
+ | | 1 | 1F | 2450, | ||
+ | | 2 | 2F | 7608, | ||
+ | | 3 | 1T | 10308, | ||
+ | |||
+ | |||
+ | * pour le modèle réduit : | ||
+ | |||
+ | ^ Mode ^ Type ^ Pulsation propre (rad/ | ||
+ | | 1 | 1F | 2450, | ||
+ | | 2 | 2F | 7611, | ||
+ | | 3 | 1T | 10314, | ||
+ | |||
+ | </ | ||
+ | </ | ||
+ | |||
+ | |||
+ | |||
+ | |||
- public/modeles/rotor_68/accueil.txt
- Dernière modification : 2023/04/14 12:36
- de solenekojtych