Design, Construction, and Setup of Low-Speed Open Circuit Wind Tunnel

In this study, the design of a wind tunnel was carried out to observe airflow through an airfoil, streamlines and turbine blades. To accommodate this, in this study a design was made of an open return wind tunnel. In this case, an open circuit wind tunnel type will be made because the construction is simpler and the manufacturing costs are relatively cheaper compared to the closed circuit wind tunnel type. The Wind Tunnel is designed with Open CLosed Wind Tunnel (OCWT) type. The OCWT is designed to consist of fan and housing, diffuser, test section, contraction, honeycomb. The OCWT design uses an operating fan to circulate air into the test section. The maximum air speed in the Test Section is 5 m/s with a flow that is closed to laminar. The recommended diffuser has a dimension of 50 cm on the side that is attached to the test section and 52 cm on the side facing the fan with an inclination angle of 1.79o. The driver uses a 16 inch exhaust fan with a power of 74 W to make the flow in the Test Section stable at a speed of 2 m/s.

This paper presents the design and manufacturing of open circuit low-speed wind tunnel. The design of the contraction cone, test section and diffuser are finalized by the numerical analysis performed on ANSYS CFD software. A unique insight into the design of the contraction cone is presented. A fifth-order polynomial is used to model the contraction cone in PRO-E software. It allowed designing the test section with minimum turbulence and flow serration and a flow velocity profile of 20 m/s. The cross-sectional area of the test section and diffuser are selected after analytical calculations. The diffuser is designed as such to avoid pressure loss by incorporation changes in the rectangular cross-section. The initial study performed on the design helped us to select the fan with suitable power. Moreover, the intake of the contraction cone is equipped with the honeycomb structure of facilitating the laminar flow into the contraction cone. Following on to the initial numerical analysis, the fabrication of the wind tunnel is performed. Besides, a separate lift/drag measuring force system is also prepared; the intuitive design is cost-effective as well as accurate. The placement of anemometer helped us to directly measure the test section velocity, which is found to be 17 m/s.

Design and construction of an open loop subsonic high temperature wind tunnel for investigation of SCR dosing systems

Wind tunnel is an instrument having wide application in aerodynamics field. It is used to study the effect of airflow around test objects. The present work deals with the design of an academic open circuit subsonic wind tunnel using J. B. Barlow’s method. The diffuser and settling chamber geometry are obtained using standard formulae. The contraction cone profile which is very crucial in ensuring uniform flow with negligible losses and boundary layer growth is obtained using MATLAB. The modeling is done using SOLIDWORKS and the geometry is analyzed for flow velocity and static pressure using ANSYS FLUENT. Analysis is performed for three contraction cone profiles and second order polynomial profile is found to be the most appropriate.

The wind tunnel is proper functioning platform for accurate aerodynamic research which helps to provides adequate environment condition around scaled model to the compatible dimension. Wind tunnel data is part of design process that used to design their model. For correcting wind tunnel data of wall and mounting effects very careful techniques are used. But it shows limitation for linear flow approximation. This research paper proposed first part of the project i.e. design calculation and simulation i.e. flow in wind tunnel and checking incompressible flow in test section over an airfoil using CFD software. Test section design in rectangular shape for proposed wind tunnel. Contraction cone has contraction ratios 7 and cross section in rectangular shape. Diffuser design in conical shape with 5° diffusion angle and area ratio 1.33. The design philosophy is discussed along method for wind tunnel calculation is outlined. Using Computational fluid dynamics (CFD), design and simulation of flow parameter are investigated with systematic way in open loop wind tunnel. It shows good quality flow in test section as well as in entire wind tunnel. The proposed wind tunnel is conformed to design and can be used for different test in the field of aerodynamics. Wind tunnel design to achieve 40 m/s speed of air with expected low intensity turbulence level. Analysis of airfoil shows that good flow quality in test section. Lift and drag coefficient plotted against angle of attack.

The The Republic of Indonesia is rich in potential for renewable energy, including abundant wind energy. This study aims to design a subsonic open return wind tunnel for testing wind turbines at low airspeeds. The testing focus includes the evaluation of blade efficiency, bearing performance, and other aspects. Testing at low airspeeds (<5 m/s) is highly relevant to the wind conditions in Indonesia. The design process utilizes Computer Aided Design (CAD), while data collection and analysis are conducted through Computer Aided Engineering (CAE) simulations and theoretical calculations. The wind tunnel comprises components such as contraction, honeycomb, test section, diffuser, and support structure. Airflow over the turbine blades can be observed using smoke visualization in the test section. This research is expected to provide practical contributions to the development of low-speed wind turbines in Indonesia.

The design and fabrication of a low-speed wind tunnel (LSWT), which is a critical component for testing and comprehending aircraft aerodynamics, is presented in this study. Despite the increasing prominence of computational fluid dynamics (CFDs) in manufacturing engineering, wind tunnels remain essential for the intricate development of aircraft and automobile designs with complex flow interactions. Using SolidWorks, we focused on controlling flow turbulence approaching the test section, emphasizing performance and quality parameters. The construction of the wind tunnel used plywood with an axial fan regulating the airspeed, and Arduino facilitated data acquisition. The drag and lift on the Y Clerk Airfoil were quantified by two load cells along the XY-axis, complemented by a Pitot Static Tube and a multitube inclined plane manometer for pressure and velocity calculation. Fusion 360 simulation software was used to analyze pressure and velocity profiles at speeds ranging from 10 to 20 m/s, providing a comprehensive quantitative evaluation of the wind tunnel’s capabilities. By emphasizing both design innovation and quantitative performance metrics, this study underscores the continuing significance of wind tunnels in engineering.

A multipurpose subsonic wind tunnel facility has been designed for the Korea Air Force Academy in South Korea, and construction of this facility is nearing completion. This wind tunnel will be used in development of aircraft and ground vehicles as well as for basic studies in aeronautical engineering. The facility includes the wind tunnel and a building complex with offices, workshops, and test hall. The main test section dimensions are 2.45 m high, 3.5 m wide and 8.7 m long. Velocity ranges from 5 to 92 m/s with a fan power of 2,000 kW. High flow quality is achieved, with turbulence intensity designed to be below 0.05%rms (u'/U) and 0.1%rms (v'/U, w'/U). How angularity is designed to be less than +.0.1 deg. The wind tunnel has interchangeable test sections, several model support systems, a variety of instrumentation systems, and a probe traverse system. The external balance can be elevated to provide high accuracy for the various model types and to accommodate model/test section exchanges. The test facility systems and the building are integrated to provide excellent model handling and testing productivity. *Cheong-Ju, South Korea t Tullahoma, Tennessee 37388 Copyright * 1998 by Sverdrup Technology, Inc. Published by American Institute of Aeronautics and Astronautics, Inc., with permission. INTRODUCTION The government of the Republic of Korea and Korean industry are committed to establishing the capability for future aircraft development in Korea. The scope of this capability includes both military and civil systems. To meet this commitment, wind tunnels of sufficient size and capability are required. Several projects are now underway to support this effort. One of them, a subsonic wind tunnel undertaken by the Republic of Korea Air Force Academy (KAFA), is the subject of this paper. KAFA selected Sverdrup Technology, Lie. as the turnkey supplier of the subsonic wind tunnel, including preliminary and final design and construction services. Final design work has been completed and is covered in the present paper. Construction/installation and commissioning/calibration phases will be completed in 1998, and the results of that work will be presented in a future paper. FACILITY REQUIREMENTS During initial facility planning studies, KAFA configured the Subsonic Wind Tunnel as a closedcircuittype with interchangeable, atmospheric-pressure test sections. To support the Republic of Korea's commitment to aircraft and ground vehicle systems, the main testing activities planned to be conducted in the facility are: • Configuration optimization of aircraft • Development of high hit devices • Wing/body integration American Institute of Aeronautics and Astronautics Copyright© 1997, American Institute of Aeronautics and Astronautics, Inc. • Ground passenger vehicle aerodynamics • Building aerodynamics • Full aircraft component integration • Rotor aerodynamics • Helicopter aerodynamics Facility design requirements were established based on these testing activities. The requirements for test-type, test section size, performance, and flow quality are summarized in Tables 1 and 2. Compared to other mediumand large-size subsonic facilities, the KAFA facility's performance and flow quality requirements are state-of-the-art, and they are appropriate for advanced experimental education programs and aircraft development programs.

Design and Construction of an Open-circuit Wind Tunnel with Specific Measurement Equipment for Cycling

On the enhancement of acceptable blockage of open jet wind tunnel by employing modifications based on concepts of boundary layer and jet flow for testing of aero-rotors

This paper proposes a process of determining geometrical configurations to simulating the flow in designing sub-sonic open circuit wind tunnels. Design rules that are based on empirical results and Computational Fluid Dynamics (CFD) model are integrated as a Low-Speed Wind Tunnel Design Tool. The tool allows users to undertake the automatic calculation through wind tunnel designed requirements to detailed flow fields analysis. Three configurations with the overall length of 7 to 10 meters and width from 3.5 to 4.2 meters are suggested. The design wind tunnels have the test section (cross section) of 1.7 × 1.7 meters squared and the test section velocity of 15 meters per second. The simulation results help to choose the best-designed wind tunnel configuration for manufacturing in the future.

Design Approach to Mach Number 0.5 Low Speed Subsonic Wind Tunnel

On the basis of the overall structure design and aerodynamic calculation of the annular low-speed wind tunnel, this paper uses the CFD numerical simulation technique to study the influence of the contraction curve form, the contraction ratio and the open/closed loop form of the test section on the flow field quality of the wind tunnel test section, and then gives the three-dimensional geometric model and the numerical simulation results. It is found that the best flow field quality can be obtained by using the bicubic curve, the contraction ratio of 10.24 and the closed loop form of the test section under the same fan condition. The three-dimensional modeling method is adopted in this paper, which can obtain more accurate numerical simulation result than the two-dimensional modeling method. Thus, the numerical simulation result provides a solid theoretical basis for the design and construction of the actual low-speed wind tunnel.

In the planning and design of a new wind tunnel the choice between closed and open-circuit types is a very important one. If on one hand the open –circuit solution is attractive for its low price and continuous fresh test air, on the other hand the test section flow quality is potentially affected by external winds. This sensitivity becomes especially critical at low-test speeds. Although many open-circuit wind tunnels have been built, there have been some problems either of low operating efficiency or sensitivity to external winds, or both. In this respect both ends of the tunnel are objects of concern. In the present paper, however, the authors concentrate their attention to the wind tunnel inlet section. At the Instituto Tecnologico de Aeronautica a non-return wind tunnel is currently under design. The test section flow quality requirements are very strict and the test-section turbulence level is to be as low as 0.05% of the mean flow kinetic energy. To insure that the desired turbulence level and flow uniformity at the test section is achieved the tunnel will have a 10:1 contraction, a honey comb and three screens with provision for an extra one. Further, the 35meter long facility has its inlet section, the contraction and the test section inside a 25x10 room. The diffuser, the fan section and the exit section are mounted outside the laboratory room. Figure 1 shows the tunnel layout. Although its position inside the laboratory is beneficial as does not expose the inlet section directly to the outside wind it also arises following concerns: (i) to operate the wind tunnel a large 6mx2.5m door will have to be open. Both side ends of this door will generate a shear layer exactly in front of the facility air intake (ii) the tunnel inlet section is not symmetrical in respect to the laboratory’s walls, being much closer to the one on its right-hand side. The 3.8m wide by 3.16 m high inlet is only about 20 cm away from both the floor and the ceiling of the room. In order to quantify these influences on the mean velocity distribution and on the turbulence level, at the tunnel air intake, an experimental study was made on a 1/10 scale model of the part of the tunnel to be built inside the lab.

Generally, the experimental aerodynamics is related to wind tunnel experiments. The wind tunnel design topic is very old but the development in computational fluid dynamics led to improvement in the wind tunnel design. This paper describes the design and optimization of low speed wind tunnel using CFD techniques. The new optimum wind tunnel will replace the old one featuring poor air quality and small area with lower wind speed at the test section. A computational domain was generated and adopted using ANSYS mesh generator and the solution domain was analysed by simulation technique using FLUENT CFD code in ANSYS Workbench package. The pressure drop calculations comparison between analytical, computational and experimental is included for different sections in the wind tunnel. The contraction cone was optimized using the response surface technique. The results identified that the pressure drop and turbulence level are modified as compared to the old wind tunnel.