scholarly journals Wind Tunnel Testing of ONERA-M, AGARD-B and HB-2 Standard Models at Off-Design Conditions

Aerospace ◽  
2021 ◽  
Vol 8 (10) ◽  
pp. 275
Author(s):  
Dijana Damljanović ◽  
Đorđe Vuković ◽  
Goran Ocokoljić ◽  
Biljana Ilić ◽  
Boško Rašuo
Keyword(s):  
Wind Tunnel ◽  
Standard Test ◽  
Wind Tunnel Testing ◽  
Test Results ◽  
Technical Institute ◽  
Wind Tunnel Tests ◽  
Test Conditions ◽  
Standard Models ◽  
The Military ◽  
Good Agreement

Published results for standard wind tunnel models at non-standard test conditions are quite rare and/or may not be available. It has been found that those results are a useful aid in preparations for a number of wind tunnel tests in the Military Technical Institute (VTI) in Belgrade. Test campaigns of standard models at non-standard conditions are performed to serve as an internal database for future wind tunnel tests in such environments. Those tests, that partially overlap the referenced Mach number and/or angle of attack ranges, are conducted in different VTI’s test facilities; different model sizes and support stings were used. The standard models used in static measurements in VTI, ranging from simple missile shapes and re-entry bodies to complicated airplanes, are briefly described and sample non-standard test results are given. The correlation of the test results among models and facilities has been done with references in the available ranges, and, after confirming a good agreement, it is assumed that the results are also valid in the extended ranges of conditions. These results may be useful for researchers in other wind tunnel facilities and for those who handle CFD tools.

scholarly journals Geometric Effects Analysis and Verification of V-Shaped Support Interference on Blended Wing Body Aircraft

2020 ◽  
Vol 10 (5) ◽  
pp. 1596
Author(s):  
Xin Xu ◽  
Qiang Li ◽  
Dawei Liu ◽  
Keming Cheng ◽  
Dehua Chen
Keyword(s):  
Wind Tunnel ◽  
High Speed ◽  
Pitching Moment ◽  
Straight Section ◽  
Test Results ◽  
Wind Tunnel Tests ◽  
Blended Wing Body ◽  
Support Interference ◽  
Geometric Effects ◽  
Good Agreement

A special V-shaped support for blended wing body aircraft was designed and applied in high-speed wind tunnel tests. In order to reduce the support interference and explore the design criteria of the V-shaped support, interference characteristics and geometric parameter effects of V-shaped support on blended wing body aircraft were numerically studied. According to the numerical results, the corresponding dummy V-shaped supports were designed and manufactured, and verification tests was conducted in a 2.4 m × 2.4 m transonic wind tunnel. The test results were in good agreement with the numerical simulation. Results indicated that pitching moment of blended wing body aircraft is quite sensitive to the V-shaped support geometric parameters, and the influence of the inflection angle is the most serious. To minimize the pitching moment interference, the straight-section diameter and inflection angle should be increased while the straight-section length should be shortened. The results could be used to design special V-shaped support for blended wing body aircraft in wind tunnel tests, reduce support interference, and improve the accuracy of test results.

Using Wind Tunnel Tests for Slung-Load Clearance, Part 2: Other Loads

2014 ◽  
Vol 59 (4) ◽  
pp. 1-12
Author(s):  
Reuben Raz ◽  
Aviv Rosen ◽  
Luigi S. Cicolani ◽  
Jeffery Lusardi ◽  
Bryan Gassaway ◽  
...  
Keyword(s):  
Wind Tunnel ◽  
Flight Test ◽  
Test Results ◽  
Wind Tunnel Tests ◽  
Reduce Risk ◽  
Good Agreement

The first new load is the TRIO container that can be flown in three configurations with different heights. The second new load is a ribbon bridge interior bay section. Wind tunnel results with models of the new loads exhibit in general good agreement with flight-test results. The results of the new loads strengthen further the approach of using wind tunnel tests to accelerate slung-load clearance, as well as reduce risk and cost.

Design and Production of Wind Tunnel Testing Models with Selective Laser Sintering Technology Using Glass-Reinforced Nylon

2006 ◽  
Vol 532-533 ◽  
pp. 653-656 ◽  
Author(s):  
Saeed Daneshmand ◽  
R. Adelnia ◽  
S. Aghanajafi
Keyword(s):  
Wind Tunnel ◽  
Selective Laser Sintering ◽  
Aerodynamic Characteristics ◽  
Laser Sintering ◽  
Cnc Machining ◽  
Wind Tunnel Testing ◽  
The Cost ◽  
Force Data ◽  
Good Agreement ◽  
Tunnel Testing

In this study, the ability of Selective Laser Sintering (SLS) Technology for production of wind tunnel testing models are evaluated. It has been undertaken to determine the suitability of the Model constructed with SLS method in subsonic and transonic wind tunnel testing. Two models were evaluated in this study. The first model was fabricated from aluminum 5086-H32 by a CNC machining technique. The other model had the same section but was fabricated by the selective laser sintering (SLS) process. Aerodynamic characteristics and times as well as costs of both models were measured in 0.3 to 1.2 Mach and the results were compared. The longitudinal aerodynamic data and the normal force data obtained from SLS model showed good agreement with data obtained from the aluminum model. The greatest difference in the aerodynamic data between two models is the total axial force. The time and the cost of production are considerably reduced with use of SLS model.

scholarly journals Spectral mismatch and its effect on artificial solar light source under standard test conditions

2021 ◽  
Vol 292 ◽  
pp. 01021
Author(s):  
Gao Sheng ◽  
Lu Xiaodong ◽  
Lun Shuxian
Keyword(s):  
Amorphous Silicon ◽  
Spectral Response ◽  
Solar Spectrum ◽  
Standard Test ◽  
Spectral Irradiance ◽  
Solar Light ◽  
Light Sources ◽  
Test Results ◽  
Test Conditions ◽  
The Difference

Under standard test conditions, the spectral irradiance of artificial solar light sources and the spectral response of photovoltaic devices are important factors that affect the accuracy of device test results. This paper takes the standard solar spectrum AM1.5 as a reference, and calculates the difference between the four commonly used artificial solar light sources (Arc Lamp, Q-Flash, Q-Flash w and ELH) and the standard solar spectrum AM1.5 from the perspective of spectral mismatch. The spectral mismatch factor and the output parameters of the amorphous silicon cell under the irradiation of these light sources. Calculations show that the spectral mismatch factor of Arc Lamp is only 1.005, which matches the standard solar spectrum AM1.5 best. Due to the effect of spectral mismatch, the output parameters of amorphous silicon cells will change significantly after different artificial light sources irradiate them.

Wind Tunnel Investigations for the Free Standing Tower of the Penang Second Bridge

2012 ◽  
Vol 256-259 ◽  
pp. 1577-1581
Author(s):  
Nan Luo ◽  
Ai Xia Liang ◽  
Hai Li Liao ◽  
Mei Yu
Keyword(s):  
Wind Tunnel ◽  
Vortex Shedding ◽  
Wind Tunnel Testing ◽  
Test Results ◽  
Free Standing ◽  
Turbulent Wind ◽  
Buffeting Response ◽  
Acceptable Range ◽  
Aeroelastic Model ◽  
Under Construction

The Penang Second Bridge is a new bridge under construction in Penang, Malaysia. The aerodynamic behavior of the bridge was one of the main concerns. This paper summarizes of the wind tunnel testing of the 1:40 scaled aeroelastic model testing for the free standing tower. The wind tunnel Investigations were carried out with the objective of verifying the detailed design of bridge towers through measurement of the buffeting response to turbulent wind, susceptibility to galloping instabilities and susceptibility to vortex shedding excitation in smooth oncoming flow.The test results show that explicit vortex-induced vibration was observed for the completed free standing tower, however it will not affect the safety of the tower, and the buffeting response of tower is within acceptable range under the designed wind speed.

Pressure Distributions on Sails Investigated Using Three Methods: On-Water Measurements, Wind-Tunnel Measurements, and Computational Fluid Dynamics

2011 ◽  
Author(s):  
Ignazio Maria Viola ◽  
Richard G. J. Flay
Keyword(s):  
Wind Tunnel ◽  
Wind Tunnel Test ◽  
Full Scale ◽  
Navier Stokes ◽  
Pressure Measurements ◽  
Wind Tunnel Tests ◽  
Pressure Distributions ◽  
Unstable Environment ◽  
Full Scale Tests ◽  
Good Agreement

The main results of a two-year project aimed at comparing full-scale tests, wind tunnel tests, and numerical analysis predictions are presented. Pressure measurements were obtained from both full-scale tests and wind-tunnel tests, in upwind and downwind conditions. The upwind wind tunnel test condition was modelled using a Vortex Lattice code, while the downwind wind-tunnel test was modelled using a Navier-Stokes code. The pressures obtained from the three different methods are compared on three horizontal sections of the headsail, mainsail, and asymmetric spinnaker. In general the pressures from the three experiments showed good agreement. In particular, very good agreement was obtained between the numerical computations and the wind tunnel test results. Conversely, the results from the downwind full-scale pressure measurements showed less similarity due to a slightly tightened trim being used for the spinnaker in the on-water tests. Full-scale tests allow the action of unsteadiness due to the wind, wave and yacht movements to affect the results. This unstable environment caused the asymmetric spinnaker to move around, and a tightened trim was required to prevent the spinnaker from collapsing.

Nonlinear Aeroelastic Behaviour of Compliant Airfoils

2009 ◽  
Author(s):  
Ghalib Y. Thwapiah ◽  
Flavio L. Campanile
Keyword(s):  
Wind Tunnel ◽  
Large Deformations ◽  
Wind Tunnel Test ◽  
Test Results ◽  
Linear Approach ◽  
Innovative Idea ◽  
Compliant Systems ◽  
Observed Behaviour ◽  
Analytic Prediction ◽  
Good Agreement

Since begin of the aviation and up to the present times, airfoils have always been built as rigid structures. They are designed to fly under their divergence speed in order to avoid static aeroelastic instabilities and the resulting large deformations which are not compatible with the typically low compliance of such airfoils. In recent years, research on airfoil morphing has generated interest in innovative ideas like the use of compliant systems, i.e. systems built to allow for large deformations without failure, in airfoil construction. Such systems can operate in the neighbourhood of divergence and take advantage of large aeroelastic servo-effects. This, in turn, could allow compact, advanced actuators to control the airfoil’s deformation and loads, and hence complement or even replace conventional flaps. In order to analyze and design such compliant, active aeroelastic structures a non-linear approach to static aeroelastic is needed, which takes into account the effect of large deformations on aerodynamics and structure. Such an analytical approach is presented in this paper and applied to a compliant passive airfoil as the preliminary step to the realisation of a piezoelectrically driven, active aeroelastic airfoil. Wind-tunnel test results are also presented and compared with the analytic prediction. The good agreement and the observed behaviour in the wind tunnel give confidence in the potential of this innovative idea.

scholarly journals Assessing the Capability of Computational Fluid Dynamics Models in Replicating Wind Tunnel Test Results for the Rose Fitzgerald Kennedy Bridge

CivilEng ◽  
2021 ◽  
Vol 2 (4) ◽  
pp. 1065-1090
Author(s):  
Yuxiang Zhang ◽  
Philip Cardiff ◽  
Fergal Cahill ◽  
Jennifer Keenahan
Keyword(s):  
Wind Tunnel ◽  
Bridge Deck ◽  
Wind Tunnel Test ◽  
Verification And Validation ◽  
Bridge Engineering ◽  
Test Results ◽  
Cfd Model ◽  
Cfd Simulations ◽  
Wind Tunnel Tests ◽  
The Rose

Despite its wide acceptance in various industries, CFD is considered a secondary option to wind tunnel tests in bridge engineering due to a lack of confidence. To increase confidence and to advance the quality of simulations in bridge aerodynamic studies, this study performed three-dimensional RANS simulations and DESs to assess the bridge deck aerodynamics of the Rose Fitzgerald Kennedy Bridge and demonstrated detailed procedures of the verification and validation of the applied CFD model. The CFD simulations were developed in OpenFOAM, the results of which are compared to prior wind tunnel test results, where general agreements were achieved though differences were also found and analyzed. The CFD model was also applied to study the effect of fascia beams and handrails on the bridge deck aerodynamics, which were neglected in most research to-date. These secondary structures were found to increase drag coefficients and reduce lift and moment coefficients by up to 32%, 94.3%, and 52.2%, respectively, which emphasized the necessity of including these structures in evaluations of the aerodynamic performance of bridges in service. Details of the verification and validation in this study illustrate that CFD simulations can determine close results compared to wind tunnel tests.

scholarly journals Wind Tunnel Tests of the Tu-154M Aircraft Aerodynamic Characteristics

2019 ◽  
Vol 26 (3) ◽  
pp. 113-120
Author(s):  
Andrzej Krzysiak
Keyword(s):  
Wind Tunnel ◽  
Aerodynamic Characteristics ◽  
Full Scale ◽  
Control Surface ◽  
Rolling Moment ◽  
Wind Tunnel Tests ◽  
Aircraft Model ◽  
University Of Technology ◽  
The Military ◽  
Control Surfaces

Abstract Determination of possible manoeuvres to be performed by the aircraft requires knowledge of its aerodynamic characteristics including, in particular, characteristics of the aircraft at configuration with deflected control surfaces. In this article, the wind tunnel tests results of the model of passenger Tu-154M aircraft manufactured at the scale 1:40 are presented. The model was designed and manufactured by the Military University of Technology based on the Tu-154M aircraft geometry obtained by full-scale object scanning. The model mapped all aircraft control surfaces, along with the gaps between these surfaces and the main wing part. During the tests all the model’s control surface like, flaps, ailerons, spoilers, slots, rudder, elevator and tail plane were deflected at the same deflection angles range as they are used in the full scale aircraft. The aerodynamic characteristics of the tested Tu-154M aircraft model were measured by the 6-component internal balance. Based on the obtained measurements the aircraft model aerodynamic coefficients were calculated. In the article the basic aerodynamic characteristics of the tested Tu-154M aircraft model i.e. lift, drag coefficients as well as pitching, yawing and rolling moment coefficients versus model angles of attack and sideslip angles were presented. The tests were performed in the Institute of Aviation low speed wind tunnels T-1 of the 1.5 m diameter test section at the undisturbed velocity, V∞ = 40 m/s.

scholarly journals Aerodynamic shape optimization of guided missile based on wind tunnel testing and computational fluid dynamics simulation

2017 ◽  
Vol 21 (3) ◽  
pp. 1543-1554 ◽  
Author(s):  
Goran Ocokoljic ◽  
Bosko Rasuo ◽  
Aleksandar Bengin
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Wind Tunnel ◽  
Dynamics Simulation ◽  
Navier Stokes ◽  
Technical Institute ◽  
Aerodynamic Loads ◽  
Thrust Vector ◽  
Dynamics Simulations ◽  
The Military

This paper presents modification of the existing guided missile which was done by replacing the existing front part with the new five, while the rear part of the missile with rocket motor and missile thrust vector control system remains the same. The shape of all improved front parts is completely different from the original one. Modification was performed based on required aerodynamic coefficients for the existing guided missile. The preliminary aerodynamic configurations of the improved missile front parts were designed based on theoretical and computational fluid dynamics simulations. All aerodynamic configurations were tested in the T-35 wind tunnel at the Military Technical Institute in order to determine the final geometry of the new front parts. The 3-D Reynolds averaged Navier-Stokes numerical simulations were carried out to predict the aerodynamic loads of the missile based on the finite volume method. Experimental results of the axial force, normal force, and pitching moment coefficients are presented. The computational results of the aerodynamic loads of a guided missile model are also given, and agreed well with.

Sign in / Sign up

Export Citation Format

Share Document