Two methods to experimentally investigate supersonic ground effect problems in a wind tunnel have been examined to determine their relative effectiveness compared to a more realistic, but physically unfeasible, representation of the ground effect by means of a moving ground. Most of the time, large powerful fans blow air through the tube. The nasa langley 8foot high temperature tunnel is a combustionheated hypersonic blowdown toatmosphere wind tunnel that provides flight enthalpy simulation. In other types of blowdown wind tunnels, the low pressure chamber is removed. Figure 2 shows a schematic of a typical supersonic blowdown wind tunnel with all of the. In this section of the website we shall present various types of wind tunnels and discuss some of the unique features of each type of tunnel. This page contains several timelines that trace events that impacted the awt and spc, tests conducted at the facility, and the development of wind tunnels and vacuum chambers. This catalog is a compilation of data on subsonic, supersonic, and hypersonic wind tunnels in the eastern hemisphere used for. Blowdown tunnel article about blowdown tunnel by the.
The oil dot surface flow viz technique was used in the fullscale facility to visualize the flow field. Designing an induction wind tunnel university of twente student. Advanced flow control for supersonic blowdown wind tunnel. On the figure, we show completely closed supersonic configuration. A supersonic, a hypersonic and a ballistic windtunnel are also part of the early aeronautical research history at kth. Windtunnel development of an sr71 aerospike rocket. Design and simulation of open circuit blowdown type wind. For most open circuit tunnels, fan assemblies are located downstream of the test section and air is drawn through the wind tunnel with suction. A supersonic, a hypersonic and a ballistic wind tunnel are also part of the early aeronautical research history at kth. The performance of this supersonic blowdown wind tunnel is analyzed theoretically and experimentally. Wind tunnels langley 20inch mach 6 tunnel the 20inch mach 6 tunnel is a blowdown wind tunnel that uses dry air as the test gas.
Pdf a computerbased, proportionalintegral control system for supersonic blowdown wind. Stagnation temperature control in blowdown wind tunnels. The design of wind tunnel components, as well as their stress analysis, was conducted using solidworks. Hypersonic wind tunnel hwt also a blowdown wind tunnel run times typically 45 seconds with 45 minute turnaround blows down to vacuum mach 5, 8, and 14 using different test sections 18 diameter test section testing similar to twt. Methods for investigating supersonic ground effect in a. Research in the area of wind tunnel flow parameters control has been intensified in recent years, in an attempt to improve quality and efficiency of the wind.
Please read our short guide how to send a book to kindle. The object being tested is held securely inside the tunnel so that it remains stationary and does not move. The university of texas at arlington has developed a subscale blowdown wind tunnel for aeropropulsion experiments fig. Adapting a blowdown type wind tunnel for ground effect. It is mostly used to study flow patterns around bodies and measure aerodynamic forces on them. In this paper, the design and application of a flc is discussed to control the plenum chamber temperature for a blowdown supersonic wind tunnel bswt with the aim of achieving the accurate and desired results. These corrections generally fall into two categories. Minimum operating reynolds numbers were adequate for these. Compressed air is injected into the back end of the tunnel by a. Altitude wind tunnel timelines nasa lewis researchers go over the atlascentaur test setup with general dynamics technicians inside spc no. The control strategy is designed based on the state estimation of a real blowdown wind tunnel, which is carried out under an ekf structure. Design and evaluation of a wind tunnel with expanding corners 3 l2000, was built in 1963 and is still used for aeronautical research.
Based on these considerations, it was decided to design and fabricate a supersonic wind tunnel with a reasonable run time of 30 seconds, using the pressure vessel available in the laboratory. For students, wind tunnel experience with shock and expansion waves makes an excellent addition to theoretical studies. A wind tunnel simulates the conditions of an aircraft in flight by causing a highspeed stream of air to flow past a model of the aircraft or part of an aircraft being tested. A fixed geometry, twodimensional contoured nozzle with parallel. Stagnation pressure transient control in a supersonic blowdown. Altitude wind tunnel timelines glenn research center nasa. Blowdown tunnel article about blowdown tunnel by the free. May 05, 2015 on the figure, we show a schematic drawing of a blowdown wind tunnel. I will include some basic illustrations, photographic details, supplier information and the recommendations that i would consider if i decide to construct another wind tunnel. Pressure measurement in a blowdown wind tunnel sciencedirect. Hypersonic tunnel facility glenn research center nasa. A design method is presented for limiting the variation of stagnation temperature in a blowdown wind tunnel so that the resultant reynolds number variation of. Prediction of total pressure characteristics in the settling chamber of a supersonic blowdown wind tunnel volume 115 issue 1171 g.
Jun 11, 2008 two methods to experimentally investigate supersonic ground effect problems in a wind tunnel have been examined to determine their relative effectiveness compared to a more realistic, but physically unfeasible, representation of the ground effect by means of a moving ground. On the figure, we show a schematic drawing of a blowdown wind tunnel. Library of congress federal research division aeronautical wind tunnels eastern hemisphere. A suction type continuous operation supersonic up to mach 1. The use of tandem ejector pumps in an intermittent. Damljanovi military technical institute, belgrade, serbia. Although great advances in computational methods have been made in recent years, wind tunnel tests remain essential for obtaining the full range of data required to guide detailed design decisions for various practical engineering. The ejectors are run from the same supply as the tunnel itself, but because they are only used at low reynolds numbers when the cascade mass flow is small. The wind loads provided by wind engineering specialists have a major e.
Utility boilers, operating below 5000 kpa often use sodium zeolite andor hot or cold lime softening, in which case the continuous blowdown will be in constant operation, and the intermittent blowdown will be performed once per day. Transonic closed circuit, continuous flow wind tunnel. Publication date 195005 topics aeronautics publisher. It has a 3 m long test section of 2 2 m2 cross section and a maximum speed of 62 ms. Blowdown tunnel definition of blowdown tunnel by merriam. There are several possible configurations for a blowdown tunnel. The air is heated to a maximum temperature of approximately 1100r by an electrical resistance heater. In the present paper an open circuit blow down type wind. Design and simulation of open circuit blowdown type wind tunnel. Design of a blowdown supersonic wind tunnel clark, raymond l. Types of wind tunnel closedtype opentype blowdown shock tube. For blowdown wind tunnels, however, air is blown down into the wind tunnel by a fan or centrifugal blower. A study of pressure control for a blowdown wind tunnel. Details on the various aspects of the supersonic windtunnel and its components can be found in the text by anderson 1,2.
Pdf supersonic blowdown wind tunnel control using labviewtm. A wind tunnel that is closed and recirculates the air through the test section is called a closed return tunnel. Design of a blowdown supersonic wind tunnel clark, raymond l download bok. Philpott the hatfield polytechnic school of engineering, po box 109, hatfield, herts all0 9ab, england an automatic system for steady pressure measurement in a small handcontrolled supersonic wind tunnel is described. Wind tunnel inroduction wind tunnel gas technologies. Design of a blowdown supersonic wind tunnel clark, raymond. Pdf development and performance investigation of supersonic. A tandem ejector pumping system has been applied to an intermittent blowdown tunnel for cascade testing to achieve subatmospheric exit pressures and extend the operating range substantially. The use of tandem ejector pumps in an intermittent blowdown. Open the saved file and check the pressures and velocities. The test section sits at the end of a supersonic nozzle. A blowdown wind tunnel has a high pressure vessel upstream of the test section and a low.
This book collects original and innovative research studies on recent applications in wind tunnel tests, exhibiting various investigation directions and. The application of fuzzy logic controllers flcs to the control of nonlinear processes, typically controlled by a human operator, is a topic of much study. The hypersonic tunnel facility htf at nasas plum brook station located in sandusky, oh, originally designed to test nuclear thermal rocket nozzles, is a hypersonic mach 5, 6, and 7 blowdown, nonvitiated freejet facility that tests largescale hypersonic airbreathing propulsion systems. One of the distinctive advantages of the proposed approach is its adaptability to a wide range of operating conditions for blowdown wind tunnels. Prediction of total pressure characteristics in the. Windtunnel facilities two windtunnel facilities were used to test the lasre con. A study of pressure control for a blowdown wind tunnel by kanaga, f. Design and simulation of open circuit blowdown type wind tunnel conference paper pdf available december 2012 with 2,010 reads how we measure reads. Enhancing the supersonic wind tunnel performance based on. Prediction of total pressure characteristics in the settling. Blowdown wind tunnels are a special type of open circuit wind tunnel. I will include some basic illustrations, photographic details, supplier information and the recommendations that i would consider if i. Highspeed internal flows are complex and are often associated with shockwaveboundarylayer interactions. Windtunnel article about windtunnel by the free dictionary.
Design and construction of a supersonic wind tunnel worcester. The object can be a small model of a vehicle, or it can be just any part of a. Although great advances in computational methods have been made in recent years, wind tunnel tests remain essential for obtaining the full range of data required to guide detailed design decisions for various practical engineering problems. Experimental data were compared with the results of numerical simulations. Since tap 0 is the only tap connected to the wind tunnel, readings from tap 0. Blow down wind tunnels aerolab low turbulent wind tunnel. Aerolab offers variable mach number supersonic wind tunnels in test section sizes from 1inch x 1inch 2. A study of pressure control for a blowdown wind tunnel core. Production of wind tunnel testing models with use of rapid. May 05, 2015 the tunnel at the lower right of the figure is an open return tunnel.
Blowdown tunnel definition is an intermittent wind tunnel in which the air flow is produced by rapid discharge of a highpressure storage tank or by suction from an evacuated reservoir. A wind tunnel in which stored compressed gas is allowed to expand through a test section to provide a stream of gas or air for model testing. During a supersonic run of a blowdown wind tunnel, temperature of air in the. The wind tunnel moves air around an object, making it seem as if the object is really flying. Isbn 9789533072951, pdf isbn 9789535159773, published 20110210. A study of pressure control for a blowdown wind tunnel by f. Design and evaluation of a windtunnel with expanding corners 3 l2000, was built in 1963 and is still used for aeronautical research. A supersonic windtunnel consists of a nozzle block, testsection and a diffuser. The tunnel at the lower right of the figure is an open return tunnel. The nasa langley 8foot high temperature tunnel is a combustionheated hypersonic blowdowntoatmosphere wind tunnel that provides flight enthalpy simulation. Windtunnel development of an sr71 aerospike rocket flight.
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