ReadMe ############################################################################################################################################################################################################# This data collection consists of measurements of the noise radiated by a finite length airfoil with different airfoil profiles with sinusoidal and porous tips at a range of angles of attack and Reynolds number. ############################################################################################################################################################################################################# This data colleciton consists of: --> 1 folder for processed data, named 'Processed_data' --> 2 subfolders consist of one-third-octave band tip noise spectra for NACA0012 and NACA6412 --> NACA0012 consists of 38 subfolders --> NACA6412 consists of 18 subfolders --> OnethirdOctaveband_freq.txt --> 1 folder for spectra, named 'Spectra' --> 2 subfolders consist of one-third-octave band tip noise spectra in .tif for NACA0012 and NACA6412 --> NACA0012 consists of 38 one-third-octave band tip noise spectra in .tif --> NACA6412 consists of 18 one-third-octave band tip noise spectra in .tif --> Positions_of_47_microphones.csv --> Noise_spectra.m --> 1 folder for raw data for each table and figure in the paper, named 'Raw_data' ############################################################################################################################################################################################################# This file includes following sections: 1. Prerequisites 2. Detailed analysis 2.1. File name 2.2. Spectra 3. Recommendation (*) Some examples of acoustic spectra in one-third-octave band in .tif format are presented in the 'Spectra' folder. Please refer to Section 2.1 for the files naming rules. ####################################################### 1. Prerequisites #################################################################### [Please make sure all the prerequisites are met before processing the data] 1/1 Install Matlab (version 2018b used by authors) --> Please follow the link (https://www.mathworks.com/products/matlab.html) and get it installed (licence is required) ####################################################### 2. Detailed analysis ################################################################# ########## 2.1. File name NACAxx12: airfoil profile for the NACA 4-digit airfoil, including NACA 0012 and NACA 6412. T: tripping condition. The airfoil is tripped on both sides at the 10 % chord length. AaWb: this is the parameter for sinusoidal tips. --> A is the amplitude of the tip, a = 3, 5, 10, 3 to 10 (from the leading edge to the trailing edge) or 10 to 3 mm (from the leading edge to the trailing edge). --> W is the wavelength and the value of b is the number of wavelengths, b = 3, 5 and 10, corresponding to the wavelength of 66.7, 40 and 20 mm, respectively. Pc: this is the parameter for porous tips. --> c = 1, 2, 3, 4, 5, 6, 7 or 8. More details can be found in Table 1. below. Table 1. Parameters for porous tips ******************************************|****************************************** *** NACA 0012 porous tips ***|*** NACA 6412 porous tips *** ******************************************|****************************************** ***** top (mm) | side (mm) | porosity % **|***** top (mm) | side (mm) | porosity % ** ******************************************|****************************************** **P1| 0.6 | 0.6 | 13.80 ***|**P1| 0.6 | 0.6 | 13.24 *** ******************************************|****************************************** **P2| 1 | 0.6 | 27.24 ***|**P2| 1 | 0.6 | 27.10 *** ******************************************|****************************************** **P3| 1 | 0.8 | 31.24 ***|**P3| 1 | 0.8 | 31.10 *** ******************************************|****************************************** **P4| 1.6 | 1.6 | 40.37 ***|**P4| 1.6 | 1.6 | 41.36 *** ******************************************|****************************************** **P5| 2 | 2 | 50.03 ***|**P5| 2 | 2 | 50.23 *** ******************************************|****************************************** **P6| 1 | 0 | 22.10 ***|**P6| 1 | 0 | 21.95 *** ******************************************|****************************************** **P7| 0 | 0.6 | 5.14 ***|**P7| 0 | 0.6 | 5.14 *** ******************************************|****************************************** **P8| 1(TE) | 1(TE) | 22.85 ***|**P8| 1(TE) | 1(TE) | 23.39 *** ******************************************|****************************************** p: varies from 1 to 9, corresponding to the Reynolds number of 25 to 225k (25:25:225), respectively. A typical file would be named as follows: file = 'NACAxx12 TipGeometry TrippingCondition ReynoldsNumberSeries(p)' where xx = '00' and '64' TipGeometry = 'A3W3', 'A5W3', 'A10W3', 'A3W5', 'A5W5', 'A10W5', 'A3W10', 'A5W10', 'A10W10', 'A3to10W5' and 'A10to3W5' 'P1', 'P2', 'P3', 'P4', 'P5', 'P6', 'P7' and 'P8' TrippingCondition = 'T' and none (for non-tripped cases) ReynoldsNumberSeries(p) = 'p1', 'p2', 'p3', 'p4', 'p5', 'p6', 'p7', 'p8' and 'p9' For example: NACA0012A3to10W5p1.txt is the processed data for NACA0012 airfoil with sinusoidal tip (amplitude of 3 to 10 mm from the leading edge to the trailing edge, number of wavelength of 5, corresponding to a wavelength of 20 mm) at all angles of attack (0, 5, 10, 15 and 20 deg) and Reynolds number of 25000, based on chord. NACA6412TP5p9.txt is the processed data for tripped NACA6412 airfoil with porous tip (porosity of 50.23 %) at all angles of attack (-10, 0 : 5 : 20 deg) and Reynolds number of 225000, based on chord. OnethirdOctaveband_freq.txt is the one-third-octave band centre frequency in Hz. This file can be used for all the cases to get the one-third-octave band tip noise spectra against one-third-octave band soud pressure level provided in the 'Processed_data' folder. ########## 2.2. Spectra [The processed data are in frequency domain in .txt format, which can be found in the 'Processed_data' folder. These data can be further processed using MatLab to generate spectra] >> Open 'Noise_spectra.m' in the 'Spectra' folder with MatLab. >> Enter 'Suptitle'. (optional) >> Add file path for both one-third-octave band sound pressure level and frequency. For example: filename1=strcat('filepath/filenamep',num2str(m),'.txt') and filename2='filepath/OnethirdOctaveband_freq.txt' 'filepath/filename' for both lines should be replaced by the same directory for 'Processed_Data' folder in this data collection. Please only change 'filepath/filename' and keep the rest of these two lines unchanged. >> Change the legend. Delete the unwanted angle of attack in line 25. For example: 0 : 5 : 20 deg for NACA0012 and -10, 0 : 5 : 20 deg for NACA6412. >> Figure settings. (optional) Please refer to the link below for further details: https://www.mathworks.com/help/matlab/ref/plot.html. >> The range of x axis (frequency) and y axis (sound pressure level) can be changed by changing 'xlim ([1000 20000])' and 'ylim ([0 80])', respectively. >> Run the file. Click the green triangle button named 'Run' on the top of the window or click F5 on the keyboard. ####################################################### 3. Recommendation ################################################################# Authors highly recommend that readers get access to the whole database, including the microphone time pressure histories (raw data), sound maps and Python scripts, and proceed further analysis of interests. The size of the raw data is too large to be stored online and accessed without any login credentials. The whole data collection and more details can be found at: Moreau Danielle, Zhang Tingyi, Geyer Thomas, Doolan Con: Tip vortex formation noise produced by wall-mounted finite airfoils with porous and sinusoidal tip geometries . UNSW.dataset. https://doi.org/10.26190/5daf77c9c7f43 >>All the best with your research!<<