Pub Date : 1993-09-20DOI: 10.1109/ICIASF.1993.687651
G. I. Johnson
A calibration rig has been designed and built for balances to be used in the new TI500 transonic wind tunnel at FFA. This rig can accomodate sting mounted as well as halfmodel balances with one to six components and typically a normal force of up to 50 kN. An optimized set of calibration loads is generated via menu on a dedicated computer and the loads are applied by means of pneumatic actuators under control of the same computer. This report describes the principles of the rig and some experiences obtained during its development. Operational status of the rig with and without a master balance coupled in series with the object balance is reported as well as various problems encountered in the progress of development to adapt the rig to various balance types and load ranges. Background A new type of automatic rig for calibration of wind tunnel balances was first suggested at FFA in 1982. This rig was a non-repositioning device characterized by attachement of the object balance at its model end to a rigid platform, instrumented and calibrated as a master balance for reference. However, since this was a new concept for calibration of wind tunnel balances, the idea was at f i t cautiously received at FFA. Later on, in 1985. when plans were being developed for our new transonic wind tupnel, T1500, a corresponding new rig was required for high calibration loads and high production capacity. At this time the plans were accepted for such a rig according to the new concept and the rig structure was completed in 1988. This device was designated at FFA as the MK15 wind tunnel balance calibration rig [I]. Description of the MK15 calibration rig. In the following the MK15 calibration rig (Figure 1) is described on the basis of main requirements in the rig specification [2]. Functional principles The non-repositioning principle is used to make the rig a low cost device, adaptable for automation by computer. Necessary corrections of calibration loads may be obtained via deflection measurements and computer software [31. In order to facilitate application of this method, the object balance is installed by its model end directly fastened to the rigid rig frame or to an intermediate very stiff master balance bolted to the rig frame (Figure 2). Use of a master balance requires accurate calibration of this balance preceding the object balance calibration. One reason for choosing the master balance method together with the non-repositioning principle was that better accuracy could be expected since calibration errors due to deflection would be largely reduced. Another advantage would be the possibility of fast object balance calibration since deflection measurements are not needed in this case. Flexibility of application The calibration rig is made to accept a large variety of wind tunnel balances for one to six component loads, half model balances as well as box type and sting mounted balances. All component loads may be applied singly or in any combination. Besides
{"title":"Experience of an Automatic Rig for Calibration of Wind Tunnel Balances at FFA","authors":"G. I. Johnson","doi":"10.1109/ICIASF.1993.687651","DOIUrl":"https://doi.org/10.1109/ICIASF.1993.687651","url":null,"abstract":"A calibration rig has been designed and built for balances to be used in the new TI500 transonic wind tunnel at FFA. This rig can accomodate sting mounted as well as halfmodel balances with one to six components and typically a normal force of up to 50 kN. An optimized set of calibration loads is generated via menu on a dedicated computer and the loads are applied by means of pneumatic actuators under control of the same computer. This report describes the principles of the rig and some experiences obtained during its development. Operational status of the rig with and without a master balance coupled in series with the object balance is reported as well as various problems encountered in the progress of development to adapt the rig to various balance types and load ranges. Background A new type of automatic rig for calibration of wind tunnel balances was first suggested at FFA in 1982. This rig was a non-repositioning device characterized by attachement of the object balance at its model end to a rigid platform, instrumented and calibrated as a master balance for reference. However, since this was a new concept for calibration of wind tunnel balances, the idea was at f i t cautiously received at FFA. Later on, in 1985. when plans were being developed for our new transonic wind tupnel, T1500, a corresponding new rig was required for high calibration loads and high production capacity. At this time the plans were accepted for such a rig according to the new concept and the rig structure was completed in 1988. This device was designated at FFA as the MK15 wind tunnel balance calibration rig [I]. Description of the MK15 calibration rig. In the following the MK15 calibration rig (Figure 1) is described on the basis of main requirements in the rig specification [2]. Functional principles The non-repositioning principle is used to make the rig a low cost device, adaptable for automation by computer. Necessary corrections of calibration loads may be obtained via deflection measurements and computer software [31. In order to facilitate application of this method, the object balance is installed by its model end directly fastened to the rigid rig frame or to an intermediate very stiff master balance bolted to the rig frame (Figure 2). Use of a master balance requires accurate calibration of this balance preceding the object balance calibration. One reason for choosing the master balance method together with the non-repositioning principle was that better accuracy could be expected since calibration errors due to deflection would be largely reduced. Another advantage would be the possibility of fast object balance calibration since deflection measurements are not needed in this case. Flexibility of application The calibration rig is made to accept a large variety of wind tunnel balances for one to six component loads, half model balances as well as box type and sting mounted balances. All component loads may be applied singly or in any combination. Besides","PeriodicalId":398832,"journal":{"name":"International Congress on Instrumentation in Aerospace Simulation Facilities,","volume":"64 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122002161","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1993-09-20DOI: 10.1109/ICIASF.1993.687664
N. Chokani, S. P. Cook, G.P. Doggett
{"title":"Recent Contributions to the Focusing Schlieren Technique","authors":"N. Chokani, S. P. Cook, G.P. Doggett","doi":"10.1109/ICIASF.1993.687664","DOIUrl":"https://doi.org/10.1109/ICIASF.1993.687664","url":null,"abstract":"","PeriodicalId":398832,"journal":{"name":"International Congress on Instrumentation in Aerospace Simulation Facilities,","volume":"580 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116264354","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1993-09-20DOI: 10.1109/ICIASF.1993.687667
J. Blaisot, D. Allano, M. Ledoux
{"title":"Sizing Method for Measurement of Objects out of the Focus Plane through an Imaging Technique","authors":"J. Blaisot, D. Allano, M. Ledoux","doi":"10.1109/ICIASF.1993.687667","DOIUrl":"https://doi.org/10.1109/ICIASF.1993.687667","url":null,"abstract":"","PeriodicalId":398832,"journal":{"name":"International Congress on Instrumentation in Aerospace Simulation Facilities,","volume":"136 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133924334","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1993-09-20DOI: 10.1109/ICIASF.1993.687685
R. J. Murphy, K. S. Hartmann, D. P. Rogers
Much effort has been applied to using the Fourier transform to determine the Doppler frequency contained in an unknown burst. This process consists of digitizing the time signal, performing a fast Fourier transform, and looking for the highest spectral peak. Since there is not sufficient resolution in the line spectra to provide an adequate estimate of the Doppler frequency, interpolation techniques are applied to measure the peak in the spectra, when, theoretically, it lies between the frequencies defined by the transform. This interpolation process is normally based on the magnitude of the spectra near the peak, and the shape of the curve realized by the transform. Even though, in many cases, a high-resolution complex transform has been performed, the phase information has been discarded. The phase information, however, is of significant value. In fact, it is possible to estimate the frequency of an under-sampled signal after aliasing, by evaluating the phase relationships of the transform data (I). This paper examines the phase produced by the fast Fourier transform for different frequencies between the line spectra. The phase measurement itself is compliceted by the fact that the sampling is not synchronized to the Doppler signal. Nevertheless, the variation in phase is used to predict the actual Doppler frequency, when its approximate location is known by the peak in the spectra. For this work the parabolic estimator is used to interpolate the Doppler frequency from the transform signal, and the error is plotted as a function of the position between the Spectra. With the phase estimator applied also, it is shown that the error in the estimate is reduced. Phase information used to estimate Doppler frequency provides the opportunity not only to improve the accurracy of LV signal processing instrumentation, but also offers the possibility of improving the signal processing rate for these instruments. Estimate of the error when noise is present in the signal has not yet been performed. Further work will concentrate on research in this area. This manuscript would not be completed on time. If you are interested in it, please contact : ICIASF '93 Mr. Jay R. MURPHY Macrodyne Incorporated P.O. Box 376 CLifton Park New York, 12065, USA Tel. (518) 383 3800 FAX (518) 383 0049
利用傅里叶变换来确定未知脉冲中的多普勒频率已经花费了大量的精力。该过程包括对时间信号进行数字化，进行快速傅里叶变换，并寻找最高的频谱峰。由于线谱中没有足够的分辨率来提供对多普勒频率的充分估计，因此应用插值技术来测量光谱中的峰值，当理论上它位于由变换定义的频率之间时。这种插值过程通常是基于峰值附近光谱的大小，以及通过变换实现的曲线形状。即使在许多情况下，执行了高分辨率的复杂变换，相位信息也被丢弃了。然而，相位信息具有重要的价值。事实上，通过评估变换数据的相位关系(I)，可以估计混叠后欠采样信号的频率。本文研究了在线谱之间对不同频率进行快速傅立叶变换所产生的相位。相位测量本身由于采样不与多普勒信号同步而变得复杂。然而，相位的变化是用来预测实际的多普勒频率，当它的大致位置是已知的光谱中的峰。在这项工作中，使用抛物估计器从变换信号中插值多普勒频率，并将误差绘制为光谱之间位置的函数。结果表明，在相位估计器的作用下，估计误差减小。相位信息用于估计多普勒频率，不仅可以提高低压信号处理仪器的精度，而且还可以提高这些仪器的信号处理速率。当信号中存在噪声时的误差估计尚未执行。今后的工作将集中在这方面的研究。这份手稿不能按时完成。如果您对此感兴趣，请联系:ICIASF '93 Mr. Jay R. MURPHY Macrodyne Incorporated邮编:12065，美国纽约克里夫顿公园376号电话(518)383 3800传真(518)383 0049
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Pub Date : 1993-09-20DOI: 10.1109/ICIASF.1993.687675
A. Boutier, J. Lefèvre, D. Soulevant, F. Dunand
Tests achieved at DNW (windtunnel of NLR) on an helicopter in forward flight conditions had two main purposes: on the one hand to record the components of the velocity vector in a 2D vertical frame around the blade, and on the other hand to simultaneously measure the position of the 2 m long blade which is rotating at a speed of 1050 rpm. Two series of measurements have been performed: the first one in a closed test section (8 m x 10 m) with a working distance of 2.7 m, the second one in an open test section for which this working distance was increased up to 5 m. The optical and mechanical set-up, the synchronization of the measurements and the blade attitude measurement technique are described; the: most typical results are presented.
{"title":"2D Laser Velocimetry Near Helicopter Blades in DNW (NLR)","authors":"A. Boutier, J. Lefèvre, D. Soulevant, F. Dunand","doi":"10.1109/ICIASF.1993.687675","DOIUrl":"https://doi.org/10.1109/ICIASF.1993.687675","url":null,"abstract":"Tests achieved at DNW (windtunnel of NLR) on an helicopter in forward flight conditions had two main purposes: on the one hand to record the components of the velocity vector in a 2D vertical frame around the blade, and on the other hand to simultaneously measure the position of the 2 m long blade which is rotating at a speed of 1050 rpm. Two series of measurements have been performed: the first one in a closed test section (8 m x 10 m) with a working distance of 2.7 m, the second one in an open test section for which this working distance was increased up to 5 m. The optical and mechanical set-up, the synchronization of the measurements and the blade attitude measurement technique are described; the: most typical results are presented.","PeriodicalId":398832,"journal":{"name":"International Congress on Instrumentation in Aerospace Simulation Facilities,","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132881216","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1993-09-20DOI: 10.1109/ICIASF.1993.687661
G. Cardone, O. Di Leva, G. Carlomagno
The phenomena of flow separation of internal flows caused by suddan changes in the test-section geometry are well known. The impcrtance of such flows to engineering equipment has been stressed in many publications [1-3]. E.g. detailed information about the heat transfer distribution on thermally highly loaded gas turbine is necessary to fulfill the high demands concerning life time and reliability such as required in aero engines and stationary gas turbines. In particular, the two-dimensional backward facing step has received attention owing to its geometrical simplicity. Previous experimental findings showed that this flow geometry should yield a simple flow pattern with a single separation region attached to the step, as sketched in fig. 1. Furthermore, the length of the separation region was thought to be only dependent on the Reynolds number, on the step height and on the momentum thickness of the oncoming flow. Most of the existing work concentrates on either laminar or turbulent flows only, leaving out the region of transitional flow. The present work is carried out to deepen the understanding of internal flows with separation (in particular, the backward-facing step flow) by means of flow visualization and heat transfer measurements performed with an Infrared (IR) Scanning Radiometer (thermography). Application of IR thermography to this problem is advantageous on account of its relatively good spatial resolution and thermal sensitivity. Moreover, the use of IR Scanning Radiometer matches both qualitative and quantitative requirements. The essential features of the adopted thermographic system (AGEMA ERICA 900) are: it is non-intrusive; it allows a complete two-dimensional mapping of the surface to be tested; the video signal output may be treated by digital image processing [4-51. IR system allows to easily detect the presence of the other regions of detached flow (besides that close to the step) that were not measured and/or reported so far. IR camera takes the temperature maps of both sides of the channel downstream of the step. These sides consist of a very thin stainless steel foil that is heated by Joule effect; temperature maps are correlated to the heat transfer coefficient by means of the so-called heated thin foil technique [SI. Tests are carried out for Reynolds R e ranging from 100 to 5000 . Re is defined as
{"title":"Heat Transfer Measurement in a Backward-Facing Step Flow","authors":"G. Cardone, O. Di Leva, G. Carlomagno","doi":"10.1109/ICIASF.1993.687661","DOIUrl":"https://doi.org/10.1109/ICIASF.1993.687661","url":null,"abstract":"The phenomena of flow separation of internal flows caused by suddan changes in the test-section geometry are well known. The impcrtance of such flows to engineering equipment has been stressed in many publications [1-3]. E.g. detailed information about the heat transfer distribution on thermally highly loaded gas turbine is necessary to fulfill the high demands concerning life time and reliability such as required in aero engines and stationary gas turbines. In particular, the two-dimensional backward facing step has received attention owing to its geometrical simplicity. Previous experimental findings showed that this flow geometry should yield a simple flow pattern with a single separation region attached to the step, as sketched in fig. 1. Furthermore, the length of the separation region was thought to be only dependent on the Reynolds number, on the step height and on the momentum thickness of the oncoming flow. Most of the existing work concentrates on either laminar or turbulent flows only, leaving out the region of transitional flow. The present work is carried out to deepen the understanding of internal flows with separation (in particular, the backward-facing step flow) by means of flow visualization and heat transfer measurements performed with an Infrared (IR) Scanning Radiometer (thermography). Application of IR thermography to this problem is advantageous on account of its relatively good spatial resolution and thermal sensitivity. Moreover, the use of IR Scanning Radiometer matches both qualitative and quantitative requirements. The essential features of the adopted thermographic system (AGEMA ERICA 900) are: it is non-intrusive; it allows a complete two-dimensional mapping of the surface to be tested; the video signal output may be treated by digital image processing [4-51. IR system allows to easily detect the presence of the other regions of detached flow (besides that close to the step) that were not measured and/or reported so far. IR camera takes the temperature maps of both sides of the channel downstream of the step. These sides consist of a very thin stainless steel foil that is heated by Joule effect; temperature maps are correlated to the heat transfer coefficient by means of the so-called heated thin foil technique [SI. Tests are carried out for Reynolds R e ranging from 100 to 5000 . Re is defined as","PeriodicalId":398832,"journal":{"name":"International Congress on Instrumentation in Aerospace Simulation Facilities,","volume":"511 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132518587","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1993-09-20DOI: 10.1109/ICIASF.1993.687682
C. S. Moraitis
We present in this paper a technique which allows for three-dimensional instantaneous velocity measurements, conceptually very similar to Particle Image Velocimetry (PIV). Since details on the mathematical model describing the optical processing on which the technique relies have been presented elsewhere, we limit ourselves to a brief presentation here. Emphasis is given on the presentation of unpublished details on the accompanying image processing algorithms.
{"title":"Three-Dimensional Particle Image Velocimetry by Optical Processing of Holographic Records","authors":"C. S. Moraitis","doi":"10.1109/ICIASF.1993.687682","DOIUrl":"https://doi.org/10.1109/ICIASF.1993.687682","url":null,"abstract":"We present in this paper a technique which allows for three-dimensional instantaneous velocity measurements, conceptually very similar to Particle Image Velocimetry (PIV). Since details on the mathematical model describing the optical processing on which the technique relies have been presented elsewhere, we limit ourselves to a brief presentation here. Emphasis is given on the presentation of unpublished details on the accompanying image processing algorithms.","PeriodicalId":398832,"journal":{"name":"International Congress on Instrumentation in Aerospace Simulation Facilities,","volume":"60 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115737554","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1993-09-20DOI: 10.1109/ICIASF.1993.687680
B. Lehmam, J. Mante
This paper describes a dual-component scanning technique which makes use of the Doppler effect in scattered laser light in order to rapidly scan velocity profiles in a flow. The method was built up by means of doubling a previously reported one-component technique. Results are given for a measurement in the flow near the exit nozzle of a1 heated air jet. They demonstrate the dynamics of the Flow field which is absolutely unstable due to the relationship between fluid densities of the hot jet and the cold ambient air. The plotted results concern the instantaneous velocity profiles, the velocity fluctuation, their vector fields and correlation parameters as the vorticity and the Reynolds shear stresses. Up to now we scanned with a rate of about 3000 pairs of velocity profiles per second. An increased laser-light intensity would improve the measurement conditions concerning the most important experimental parameters.
{"title":"Experimental Analysis of Turbulent Structures by Means of Rapid Two-Component Laser-Doppler Scanning","authors":"B. Lehmam, J. Mante","doi":"10.1109/ICIASF.1993.687680","DOIUrl":"https://doi.org/10.1109/ICIASF.1993.687680","url":null,"abstract":"This paper describes a dual-component scanning technique which makes use of the Doppler effect in scattered laser light in order to rapidly scan velocity profiles in a flow. The method was built up by means of doubling a previously reported one-component technique. Results are given for a measurement in the flow near the exit nozzle of a1 heated air jet. They demonstrate the dynamics of the Flow field which is absolutely unstable due to the relationship between fluid densities of the hot jet and the cold ambient air. The plotted results concern the instantaneous velocity profiles, the velocity fluctuation, their vector fields and correlation parameters as the vorticity and the Reynolds shear stresses. Up to now we scanned with a rate of about 3000 pairs of velocity profiles per second. An increased laser-light intensity would improve the measurement conditions concerning the most important experimental parameters.","PeriodicalId":398832,"journal":{"name":"International Congress on Instrumentation in Aerospace Simulation Facilities,","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126195955","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1993-09-20DOI: 10.1109/ICIASF.1993.687648
B. Ewald
For airplane development and for basic aerodynamic research as well force testing is the main task in the wind tunnel. Rising requirements for accuracy resulted in continous development and improvement of force testing technology. The concept of the cryogenic wind tunnel is an additional challenge for the force balance. At least the same accuracy as in conventional tunnels is requested over a range of 200 Kelvin.
{"title":"Advanced Force Teating Technology for Cryogenic and Conventional Wind Tunnels","authors":"B. Ewald","doi":"10.1109/ICIASF.1993.687648","DOIUrl":"https://doi.org/10.1109/ICIASF.1993.687648","url":null,"abstract":"For airplane development and for basic aerodynamic research as well force testing is the main task in the wind tunnel. Rising requirements for accuracy resulted in continous development and improvement of force testing technology. The concept of the cryogenic wind tunnel is an additional challenge for the force balance. At least the same accuracy as in conventional tunnels is requested over a range of 200 Kelvin.","PeriodicalId":398832,"journal":{"name":"International Congress on Instrumentation in Aerospace Simulation Facilities,","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129083275","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1993-09-20DOI: 10.1109/ICIASF.1993.687662
M. J. Wagner
{"title":"Skin Friction end Heat Transfer Measurements in Mach 6 High Reynolds Number Flows","authors":"M. J. Wagner","doi":"10.1109/ICIASF.1993.687662","DOIUrl":"https://doi.org/10.1109/ICIASF.1993.687662","url":null,"abstract":"","PeriodicalId":398832,"journal":{"name":"International Congress on Instrumentation in Aerospace Simulation Facilities,","volume":"13 3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130519524","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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