Spaceplane Longitudinal Aerodynamic Parameter Estimation by Cable-Mount Dynamic Wind-Tunnel Test

1991 ◽  
Author(s):  
Shuichi Sasa ◽  
Minoru Takizawa ◽  
Takashi Shimomura ◽  
Osamu Nonaka
Author(s):  
Alessandro Pontillo ◽  
Sezsy Yusuf ◽  
Guillermo Lopez ◽  
Dominic Rennie ◽  
Mudassir Lone

Experimental characterisation of aircraft dynamic stall can be a challenging and complex system identification activity. In this article, the authors present a method that combines dynamic wind tunnel testing with parameter estimation techniques to study the nonlinear pitching moment dynamics of a 1/12 scale Hawk model undergoing moment stall. The instrumentation setup allows direct calculation of angular acceleration terms, such as pitch acceleration, and avoids post-processing steps involving differentiation of signals. Data collected from tests, carried out at 20 m/s and 30 m/s, are used for a brief aerodynamic analysis of the observed stall hysteresis. Then an output-error-based parameter estimation process is used to parameterise dynamic stall models and furthermore, illustrate that in a scenario where the model's heave motion is constrained. The observed nonlinear behaviour arises from the nonlinear angle of attack and linear pitch rate components.


Author(s):  
Shuvrangshu Jana ◽  
Harikumar Kandath ◽  
Mayur Shewale ◽  
M Seetharama Bhat

This paper presents the analysis of propeller-induced flow effects on the dynamics of a fixed wing biplane micro air vehicle. The analysis is based on wind tunnel tests and mathematical modeling. This analysis plays a pivotal role because the propeller-induced flow has significant effects on the dynamics of fixed wing micro air vehicle due to submergence of a large portion of the wing in propeller slipstream. Although the effect of the propeller-induced flow on the various aerodynamic parameter is reported in the literature; however, its effects on overall forces, moments and vehicle dynamics are not quantified so far. In this paper, propeller-induced flow effects are modeled as a function of motor rotation speed and mathematical analysis is performed to quantify their effects. The wind tunnel test is conducted at different propeller speeds on a biplane micro air vehicle “Skylark”, having wingspan and chord length of 150 mm and 140 mm, respectively. Analysis of results shows that the propeller slipstream increases the overall lift, drag, side force, range, and endurance significantly. Propeller flow also contributes to the rolling moment and the pitching moment, while it has negligible effects on the yawing moment. It is shown that the trim angle of attack is lower when the propeller flow is considered in computing the trim conditions.


2021 ◽  
Author(s):  
David F. Castillo Zuñiga ◽  
Alain Giacobini Souza ◽  
Roberto G. da Silva ◽  
Luiz Carlos Sandoval Góes

Author(s):  
Bruno Ricardo Massucatto Padilha ◽  
Guilherme Barufaldi ◽  
ROBERTO GIL ANNES DA SILVA

2016 ◽  
Vol 7 (2) ◽  
pp. 131-138
Author(s):  
Ivransa Zuhdi Pane

Data post-processing plays important roles in a wind tunnel test, especially in supporting the validation of the test results and further data analysis related to the design activities of the test objects. One effective solution to carry out the data post-processing in an automated productive manner, and thus eliminate the cumbersome conventional manual way, is building a software which is able to execute calculations and have abilities in presenting and analyzing the data in accordance with the post-processing requirement. Through several prototype development cycles, this work attempts to engineer and realize such software to enhance the overall wind tunnel test activities. Index Terms—software engineering, wind tunnel test, data post-processing, prototype, pseudocode


2021 ◽  
Vol 11 (8) ◽  
pp. 3315
Author(s):  
Fabio Rizzo

Experimental wind tunnel test results are affected by acquisition times because extreme pressure peak statistics depend on the length of acquisition records. This is also true for dynamic tests on aeroelastic models where the structural response of the scale model is affected by aerodynamic damping and by random vortex shedding. This paper investigates the acquisition time dependence of linear transformation through singular value decomposition (SVD) and its correlation with floor accelerometric signals acquired during wind tunnel aeroelastic testing of a scale model high-rise building. Particular attention was given to the variability of eigenvectors, singular values and the correlation coefficient for two wind angles and thirteen different wind velocities. The cumulative distribution function of empirical magnitudes was fitted with numerical cumulative density function (CDF). Kolmogorov–Smirnov test results are also discussed.


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