实验方法

本网站目前正在建设中。

This website is currently under construction.

请参阅完整的美国国家航天局（NASA）通用研究模型（Common Research Model, CRM）网站以获取最新信息。

Please see the full NASA Common Research Model website for current information.

实验方法

Experimental Approach

项目的实验方法涉及多个要素，包括所使用的设施、模型本身、测试模型时的测试条件，以及应用于数据的修正。

The experimental approach to a project involves several items, including the facility used, the model itself, the test conditions where the model is tested, and corrections that are applied to the data.

相关文件与数据

Related Files and Data

NASA通用研究模型（CRM）由一个现代化的超临界跨音速机翼和一个代表宽体商用运输机的机身组成。CRM的设计巡航马赫数（Mach number）为 M∞ = 0.85，相应的额定升力系数为 CL= 0.5。

The NASA Common Research Model (CRM) consists of a contemporary supercritical transonic wing and a fuselage that is representative of a widebody commercial transport aircraft. The CRM is designed for a cruise Mach number of M∞ = 0.85 and a corresponding design lift coefficient of CL= 0.5.

其纵横比（aspect ratio）为 9.0，前导边缘（leading edge）后掠角为 35 度，机翼参考面积（S）为 3.011 平方英尺，翼展（b）为 62.47 英寸，平均空气动力弦长（c）为 7.447 英寸。模型力矩参考中心位于 MS=35.799 英寸和壁宿（Wall）=4.805 英寸处。本次测试所使用的短舱为简单的直通式短舱。

The aspect ratio is 9.0, the leading edge sweep angle is 35 deg, the wing reference area (S) is 3.011 ft2, the wing span (b) is 62.47 inches, and the mean aerodynamic chord (c) is 7.447 inches. The model moment reference center is located at MS=35.799 inches and WL=4.805 inches. The nacelles used for this test were simple, flow through nacelles.

压力分布通过位于 9 个展向机翼站位（η = 0.131, 0.201, 0.283, 0.397, 0.502, 0.603, 0.727, 0.846, 和 0.950）的 291 个压力孔，以及左侧短舱上 6 个径向站位（η = 30º, 90º, 150º, 210º, 270º, 和 330º）的 6 个压力孔在左右机翼上进行测量。所有压力测量均使用安装在机身前部的电子扫描压力（ESP）模块进行。根据 ESP 模块制造商提供的精度，表面压力测量误差应不超过 +/- 0.015 psi。这相应地意味着 Cp 值的变化不超过 +/- 0.0026。该模型使用叶片支杆装置安装在风洞中。

Pressure distributions are measured on both the left and right wings using 291 pressure orifices located in 9 span-wise wing stations (η = 0.131, 0.201, 0.283, 0.397, 0.502, 0.603, 0.727, 0.846, and 0.950) and on the left hand nacelle by 6 orifices at 6 radial stations (η = 30º, 90º, 150º, 210º, 270º, and 330º). All pressure measurements were made using Electronically Scanned Pressure (PSP) modules mounted inside the forward portion of the fuselage. Based on quoted accuracies from the ESP module manufacturer, surface pressure measurements should be in error no more than +/- 0.015 psi. This in turn would correspond to a variation of no more than +/- 0.0026 in terms of Cp. The model is mounted in the wind tunnel using a blade sting arrangement.

本次调查测试了五种不同的配置：仅机翼/机身（WB）、机翼/机身/挂架/短舱（WBPN）、机翼/机身/尾宿（Tail）=0°（WBT0）、机翼/机身/尾宿=+2°（WBT+2）以及机翼/机身/尾宿=-2°（WBT-2）。

Five different configurations were tested in the current investigation: the wing/body (WB) alone, wing/body/pylon/nacelle (WBPN), wing/body/tail=0° (WBT0), wing/body/tail=+2° (WBT+2) and wing/body/tail=-2° (WBT-2).

艾姆斯（Ames）11英尺风洞

Ames 11-ft Wind Tunnel

11 x 11 英尺跨音速风洞（11-Foot TWT）设施是位于加利福尼亚州莫菲特场（Moffett Field）的美国国家航天局艾姆斯研究中心（NASA Ames Research Center）统一计划风洞（UPWT）综合体的一部分，几代商用和军用飞机以及包括航天飞机（space shuttle）在内的美国国家航天局航天器（space vehicle）都在此进行过设计和测试。

The 11- by 11-Foot Transonic Wind Tunnel (11-Foot TWT) Facility is part of the Unitary Plan Wind Tunnel (UPWT) complex at NASA Ames Research Center at Moffett Field, California, where generations of commercial and military aircraft and NASA space vehicles, including the space shuttle, have been designed and tested.

11英尺跨音速风洞是一个闭路回流、变密度风洞，具有固定几何形状、通风的测试段以及柔性壁喷管。它是共用驱动系统驱动的三个独立测试段之一。由四台绕线转子变频感应电机驱动的三级轴流压缩机产生气流。UPWT 测试段之间模型的互换性允许在广泛的条件下进行测试。

The 11-Foot TWT is a closed-return, variable-density tunnel with a fixed-geometry, ventilated test section with a flexible wall nozzle. It is one of three separate test sections powered by a common drive system. A three-stage, axial-flow compressor powered by four wound-rotor, variable-speed induction motors, produces airflow. Interchangeability of models among the UPWT test sections allows testing across a wide range of conditions.

自 20 世纪 60 年代以来，11英尺跨音速风洞在几乎所有国内生产的商用运输机和军用固定翼机身的开发中都发挥了重要作用。该设施广泛用于机身测试和空气动力学研究，并在每一次载人航天（space flight）计划中发挥了至关重要的作用，包括美国国家航天局的新型猎户座（Orion）太空舱，宇航员将乘坐该舱前往国际空间站（International Space Station）、月球（Moon）及更远的地方。

The 11-Foot TWT has been instrumental in the development of virtually every domestically produced commercial transport and military fixed-wing airframe since the 1960s. The facility is used extensively for airframe testing and aerodynamic studies and has played a vital role in every manned space flight program, including NASA’s new Orion space capsule, on which astronauts will fly to the International Space Station, the Moon, and beyond.

兰利国家跨音速设施

Langley National Transonic Facility

作为世界上最大的加压低温风洞，国家跨音速设施（NTF）拥有复制实际飞行条件的独特能力。NTF 支持先进空气动力学概念的开发与评估、先进计算流体动力学（fluid dynamics）工具的验证，以及飞行器开发的风险降低。

The world’s largest pressurized cryogenic wind tunnel, the National Transonic Facility (NTF), possesses unique capabilities to duplicate actual flight conditions. The NTF supports advanced aerodynamic concept development and assessment, advanced computational fluid dynamics tool validation, and risk reduction for vehicle development.

NTF 提供世界上最高的跨音速雷诺数测试能力，并可使用环境温度（ambient temperature）下的常规空气作为测试气体，或使用温度低至 -250 ºF 的气态氮（由注入液氮（liquid nitrogen）膨胀而来）以达到飞行测试条件。凭借多种可定制的仪器和测量技术，该设施支持全展幅和半展幅模型测试。

The NTF provides the highest transonic Reynolds number testing capability in the world, and can use either conventional air at ambient temperatures as the test gas, or gaseous nitrogen (expanded from injecting liquid nitrogen) at temperatures as low as -250 ºF for achieving flight test conditions. With a wide range of customizable instrument and measurement techniques, both full-span and semi-span model testing is supported.

该设施具有根据模型尺寸调整测试条件的独特能力。对总温度、压力和风扇转速的独立控制，允许隔离和研究纯压缩性（马赫）效应、粘性（雷诺数）效应和气动弹性（动压）效应。压力壳内部经过热绝缘处理以确保最低的热耗（heat loss），并通过可变入口驱动系统实现响应迅速的马赫数控制。

The facility has the unique capability to adjust test conditions to match model size. Independent control of total temperature, pressure, and fan speed allow isolation and study of pure compressibility (Mach) effects, viscous (Reynolds number) effects, and aeroelastic (dynamic pressure) effects. The interior of the pressure shell is thermally insulated to ensure minimal energy consumption, and responsive Mach-number control is achieved with a variable inlet drive system.

我们专业的 GFTD 测试团队为众多知名客户提供支持，包括大型商用飞机制造商、领先的通用航空企业以及美国国家航天局的航天飞机计划。

Our expert GFTD test team supports a wide variety of notable clients, including large commercial aircraft manufacturers, leading general aviation corporations and NASA’s Space Shuttle Program.

NTF 的几何结构可在此处获取。

The geometry of the NTF is available here

欧洲跨音速风洞

European Transonic Wind Tunnel

欧洲跨音速风洞（ETW）与国家跨音速设施类似，是一个加压低温、闭路、连续流、风扇驱动的风洞。它可以在闭口和开槽壁配置下运行，用于测试从马赫数 0.15 到 M∞=1.35 的轻度超音速条件下的全模型和半模型。纯净的高质量氮气是唯一的测试气体。独立改变气体温度、压力和速度的能力允许进行纯雷诺数和/或气动弹性研究。测试段尺寸为宽 7.87 英尺（2.4 米）、高 6.56 英尺（2 米）和长约 30 英尺（9 米）。通过广角扩散器中的 2 个填充筛网，结合流场整流器（蜂窝状）和 2 个防湍流（turbulent flow）筛网，随后是固定收缩段和用于超音速运行的柔性喷管，提供了高质量的流场。此外，该风洞在再入段下游设有第二个喉道，防止高速扩散器中最终产生的流场扰动向上游传播到测试段中。

The European Transonic Wind Tunnel (ETW) is similar to the National Transonic Facility, a pressurized cryogenic, closed circuit, continuous-flow, fan-driven wind tunnel. It can be operated in closed and slotted wall configurations for testing full and half-models from Mach numbers of 0.15 up to light supersonic conditions at M∞=1.35. Pure high quality nitrogen is used as the only test gas. The capability of varying the gas temperature, pressure and speed independently allows for pure Reynolds number and/or aeroelastic investigations. The test section dimensions are 7.87 ft (2.4 m) in width, 6.56 ft (2 m) in height and about 30 ft (9 m) in length. High flow quality is provided by 2 filling screens in the wide angle diffuser combined with a flow straightener (honeycomb) and 2 anti-turbulence screens followed by a fixed contraction and a flexible nozzle for supersonic operation. Additionally, the tunnel features a second throat downstream of the re-entry preventing flow disturbances eventually generated in the high-speed diffuser from propagating upstream into the test-section.

ETW 的运行范围涵盖了 110kPa 至 450kPa 的压力和 313K 至 110K 的温度，使得在马赫数（Mach number）约为 0.85 时，全尺寸模型可达到 5000 万的最大雷诺数，半展模型可达到 9000 万。虽然风洞壳体内部进行了隔热处理以防止热耗（heat loss），但风扇产生的热量通过注入液氮（liquid nitrogen）的蒸发来补偿，液氮被喷射到压缩机上游的风洞中。有关该设施及其运行的更多详细信息，请访问 www.etw.de。

The ETW operating range covers pressures from 110kPa to 450kPa and temperatures from 313K down to 110K allowing the achievement of maximum Reynolds numbers of 50 million for full models and 90 million for semi-span models at a Mach number around 0.85. While the tunnel shell is internally insulated against heat losses the heat generated by the fan is compensated by the evaporation of the injected liquid nitrogen, which is sprayed into the tunnel upstream of the compressor. Further details about the facility and its operation can be found at www.etw.de.

ONERA S1MA 大型跨音速大气风洞

ONERA S1MA Large Transonic Atmospheric Wind Tunnel

有关在 ONERA S1MA 风洞中进行的通用研究模型（Common Research Model, CRM）测试的信息和结果可在此处找到。

Information and results of the test of the Common Research Model in the ONERA S1MA wind tunnel can be found here.

艾姆斯研究中心（Ames Research Center）11 英尺风洞

Ames 11-ft Wind Tunnel

下载一份最终的艾姆斯 11 英尺运行日志 CRM Ames Test 216 Run Log

Download a copy of the final Ames 11 foot run log CRM Ames Test 216 Run Log

下载一份艾姆斯 11 英尺变量名称 AmesT216VarNames

Download a copy of the Ames 11 foot variable names AmesT216VarNames

这项历时 5 周的调查提供了力与力矩、表面压力以及表面流场可视化数据。测试是在 500 万的弦长雷诺数下进行的。数据是在约 100º F 的温度下采集的。

The investigation, conducted over a 5-week period, provided force and moment, surface pressure, and surface flow visualization data. Testing was conducted at a chord Reynolds number of 5 million. The data were collected at temperatures of approximately 100º F.

所有呈现的数据均在 0.7 至 0.87 的自由流马赫数范围内获得。数据通常是在 500 万弦长雷诺数下，于 -3° 至 +12° 的迎角范围内获得的。进行了流向角测量，并对最终数据应用了 0.013° 至 0.067° 的上洗修正。根据别处提出的方法，应用了考虑风洞浮力和升力干扰的经典壁宿（Wall）修正。

All data presented were obtained at freestream Mach numbers ranging from 0.7 to 0.87. Data were generally obtained over an angle-of-attack range from -3° to +12° at 5 million chord Reynolds number. Flow angularity measurements were made and upflow corrections ranging from 0.013° to 0.067° were applied to the final data. Classical wall corrections accounting for tunnel buoyancy and lift interference have been applied according to the method presented elsewhere.

在艾姆斯 11 英尺风洞测试时，模型上的转捩也被固定。不过，对于本次调查，仅使用了乙烯基粘合剂转捩点（trip dots）。这些转捩点直径为 0.05 英寸，间距为 0.1 英寸。对于 500 万的弦长雷诺数，从机身侧面（SOB）到机翼折点（yehudi break）使用了 0.0035 英寸高的转捩点，从机翼折点到中翼使用了 0.003 英寸，从中翼到翼尖使用了 0.003 英寸。这些转捩点安装在 10% 弦长处。乙烯基粘合剂转捩点也被应用于机身头部，并在整个测试过程中保留。当短舱安装在模型上时，转捩点位于外表面和内表面前导边缘（leading edge）后方 0.43 英寸处。最后，当尾宿（Tail）安装在模型上时，转捩点位于 10% 弦长处，尺寸为 0.003 英寸。

Transition was also fixed on the model when tested at the Ames 11-ft wind tunnel. For this investigation, though, only vinyl adhesive trip dots were applied. These trip dots measured 0.05 inches in diameter and were spaced 0.1 inches apart. For a chord Reynolds number of 5 million, a trip dot height of 0.0035 inches was used from the SOB (side of body) to the yehudi break, 0.003 inches was used from the yehudi break to the midwing and 0.003

兰利国家跨音速设施（Langley National Transonic Facility, NTF）

inches was used from the midwing to the wing tip. These trip dots were installed at 10% chord. Vinyl adhesive trip dots were also applied at the nose of the fuselage and left on for the entire test. When the nacelles were on the model, trip dots were located 0.43 inches back from the leading edge on the outer surface and the inner surface. Finally, when the tails were on the model, trip dots were located at 10% chord and measured 0.003 inches.

下载一份 NTF 最终运行日志 CRM NTF Test 197 Run Log

Langley National Transonic Facility

下载 NTF 变量名称定义 NTFT197VarNames.v2。此文件最后更新于 2014 年 10 月 23 日。请丢弃在此日期之前从本网站下载的任何 NTF Test 197 变量名称文件。

Download a copy of the NTF final run log CRM NTF Test 197 Run Log

来自 NTF Test 197 的力与力矩数据已于 2014 年 10 月 23 日更新。请丢弃在此日期之前从本网站下载的任何 NTF Test 197 力与力矩数据。

Download the definition of the NTF variable names NTFT197VarNames.v2. This file was last updated on October 23, 2014. Please discard any variable name file for NTF Test 197 downloaded from this website before this date.

这项历时 6 周的调查提供了力与力矩、表面压力、模型变形以及表面流场可视化数据。测试是在 500 万、1980 万和 3000 万雷诺数下进行的。本文中呈现的所有雷诺数值均基于平均空气动力弦长。采集 500 万和 1980 万雷诺数的数据是为了与先前计算的 CFD 结果进行比较，所有雷诺数均用于评估雷诺数效应。1980 万雷诺数的数据是在两种不同的 q∞ 水平下采集的——即高 q∞ 和低 q∞ 条件。在相同的雷诺数下拥有两个 q∞ 水平，为数据提供了气动弹性阶跃。数据是在 -250ºF 至 120ºF 的温度范围内采集的。

The force and moment data from NTF Test 197 was updated on October 23, 2014. Please discard any force and moment data from NTF Test 197 downloaded from this website before this date.

数据通常是在 500 万雷诺数下，于 -3° 至 +12° 的迎角范围内获得；在 1980 万和 3000 万雷诺数下，于 -3° 至 +6° 的迎角范围内获得。在较高雷诺数下减小迎角范围是必要的，以确保不超过安全模型应力水平。进行了流向角测量，并对最终的 NTF 数据应用了 0.092° 至 0.173° 的上洗修正。应用了考虑模型阻塞、尾流阻塞、风洞浮力和升力干扰的经典壁宿修正。

The investigation, conducted over a 6-week period, provided force and moment, surface pressure, model deformation, and surface flow visualization data. Testing was conducted at 5, 19.8 and 30 million Reynolds number. All Reynolds number values presented in this paper are based on mean aerodynamic chord. The 5 and 19.8 million Reynolds number data were collected to provide a comparison to previously calculated CFD results and all of the Reynolds numbers were used to provide an assessment of Reynolds number effects. The 19.8 million Reynolds number data were collected at two different q∞ levels – a high and a low q∞ condition. Having two q∞ levels at the same Reynolds number provides an aeroelastic step in the data. The data were collected at temperatures ranging from -250ºF up to 120ºF.

为了确保从层流到湍流（turbulent flow）的转捩一致且可重复，并支持将风洞数据用于 CFD 验证目的的目标，应用一种经过验证且可靠的方法来固定模型上的转捩非常重要。本次调查使用了直径为 0.05 英寸、间距（中心到中心）为 0.1 英寸的 Evercoat 转捩点。对于 500 万的弦长雷诺数，从机身侧面到机翼折点使用了 0.0035 英寸高的转捩点，从机翼折点到中翼使用了 0.003 英寸，从中翼到翼尖使用了 0.003 英寸。这些转捩点安装在 10% 弦长处。高度为 0.004 英寸的乙烯基粘合剂转捩点被应用于机身头部，并在整个测试过程中保留。当短舱安装在模型上时，高度为 0.003 英寸的转捩点位于外表面和内表面前导边缘后方 0.43 英寸处。最后，当尾宿安装在模型上时，转捩点位于 10% 弦长处，高度为 0.003 英寸。

Data were generally obtained over an angle-of-attack range from -3° to +12° at 5 million Reynolds number and from -3° to +6° at 19.8 and 30 million Reynolds numbers. The reduced angle-of-attack range at the higher Reynolds number was required such that safe model stress levels would not be exceeded. Flow angularity measurements were made and upflow corrections ranging from 0.092° to 0.173° were applied to the final NTF data. Classical wall corrections accounting for model blockage, wake blockage, tunnel buoyancy, and lift interference have been applied.

欧洲跨音速风洞（European Transonic Wind Tunnel, ETW）

In order to ensure a consistent and repeatable transition from laminar to turbulent flow and to support the goal of the wind tunnel data being used for CFD validation purposes, it was important to apply a proven and reliable method to fix transition on the model. Evercoat trip dots measuring 0.05 inches in diameter and spaced 0.1 inches apart (center to center) were used for the current investigation. For a chord Reynolds number of 5 million, a trip dot height of 0.0035 inches was used from the SOB (side of body) to the yehudi break, 0.003 inches was used from the yehudi break to the midwing and 0.003 inches was used from the midwing to the wing tip. These trip dots were installed at 10% chord. Vinyl adhesive trip dots with a height of 0.004 inches were applied at the nose of the fuselage and left on for the entire test. When the nacelles were on the model, trip dots with a height of 0.003 inches were located 0.43 inches back from the leading edge on the outer surface and the inner surface. Finally, when the tails were on the model, trip dots were located at 10% chord and measured 0.003 inches in height.

由于本次调查由欧盟委员会作为ESWIRP项目的一部分资助，可用预算仅允许在有限的条件下进行测试。ETW为期5天的测试计划是基于欧洲项目组（由法国ONERA的J.L. Goddard主持）的测试需求与NTF中CRM模型既定测试条件之间的折中方案。该项目组主要致力于获取用于非定常尾流流体动力学（CFD）验证的数据。此外，还增加了一些极低雷诺数下的极曲线，旨在为日本航天局（JAXA）提供对比空气动力学数据，该机构此前已在其跨音速风洞中测试了CRM的缩比版本。

European Transonic Wind Tunnel

为实现项目的科学目标，本次活动中启用了新集成的测量功能：用于尾流分析的非定常粒子图像测速（PIV），以及结合了升级版高速大容量数据采集（data acquisition）系统的非定常平衡信号记录，并进行了非定常和定常模型变形测量。本文仅展示了力、力矩和机翼压力分布等空气动力学数据，以及机翼变形情况。尽管在12个不同的马赫数（Mach number，范围从0.25到0.87）下获取了数据，但大部分工作集中在M=0.7和模型设计马赫数0.85上。因此，为了进行预期的结果对比，NTF在这两个马赫数下的参考测试条件均经过了仔细设置和控制。为覆盖500万、1980万和3000万的相关雷诺数，风洞温度在302 K至117 K之间变化，并结合了200至300 kPa之间的相应压力。NTF和ETW的运行包线不允许在相同的q/E值下达到最小和最大雷诺数。因此，决定在较低和较高的q/E值下重复1980万雷诺数的测试，从而允许针对不同气动弹性效应下的模型变形评估进行额外对比。通过在模型处于正置和倒置位置时进行升力极曲线测试，测得全运行范围内的上洗流为0.010至0.015度。测量数据还根据过去建立的ETW实验评估结果进行了壁面干扰修正。模型迎角测量始终受到极度重视。在开始测试活动之前，即使在施加负载的情况下，也会检查模型内部相关倾角仪的电气偏移和不对中情况。此外，在应用通常用于500万弦长雷诺数测试的转捩带时也给予了特别关注。与NTF专家密切合作开展此项工作，最大限度地降低了因这一敏感项目导致后续结果不匹配的风险。

Since this investigation was funded by the European Commission as part of the ESWIRP project, the available budget only allowed for testing over a limited range of conditions. The test plan for the 5-day test campaign in the ETW was determined based on a compromise between test requirements from the European project group chaired by J.L. Goddard from ONERA-France which focused on acquiring data for CFD validations of unsteady wake flows and a repeat of the conditions at which the used CRM model had been tested in the NTF. A few polars were added at a very low Reynolds number to provide comparative aerodynamic data for the Japanese research organisation JAXA who have tested the CRM in a downscaled version in their transonic tunnel.

在NTF和ETW等设施投入使用之前，工程师们确信风洞模型具有刚性，不会受到空气动力载荷（特别是在增压设施中）产生的显著变形影响。利用这些风洞在不同压力或更好的q/E水平下建立相同雷诺数的独特能力，证明了事实恰恰相反。如今，在所有与CFD结果的对比中，对载荷下机翼形状的正确评估已成为强制性要求。从最初使用莫尔条纹（Moirée）工具开发适当的测量系统开始，ETW目前可并行运行4个系统，例如用于监测半模型主翼及所有高升力组件的形状。立体模式跟踪（SPT）系统能够监测粘贴在机翼下表面标记的空间位移。在本文报告的测试活动中，一个系统以58帧/秒的速度观测主翼，而第二个系统则以386帧/秒的速度监测非定常水平尾翼（HTP）的运动。

For achieving the scientific goal of the project, newly integrated measurement capabilities were operated during the campaign: unsteady PIV for wake flow analysis and unsteady and steady model deformation measurements combined with the recording of unsteady balance signals taking the benefit of an upgraded fast high capacity data acquisition system. In the frame of the present paper only aerodynamic data like force, moments and wing pressure distributions combined with the wing deformation are presented. Although, data were acquired at 12 different Mach numbers ranging from 0.25 to 0.87 the majority focussed on M=0.7 and the model design Mach number of 0.85. So, with respect to the intended comparison of results, the reference test conditions of the NTF at these two Mach numbers were carefully set and controlled. To cover the relevant Reynolds numbers of 5, 19.8 and 30 million the tunnel temperature was varied between 302 K and 117 K combined with corresponding pressures between 200 and 300 kPa. The operating envelopes of NTF and ETW do not allow achieving the minimum and maximum Reynolds number at the identical q/E value. Hence, it was decided to duplicate the 19.8 million Reynolds number at a lower and higher q/E value allowing an additional comparison of the model deformation assessment as a function of the different aeroelastic effects. By performing lift polars with the model in upright and inverted position the upwash could be assessed as 0.010 to 0.015 deg over the full operating range. The measured data were additionally corrected for wall interference based on the ETW experimental assessment established in the past. Extreme care is always given to the measurement of the model angle of attack. Before starting the test campaign the electrical offset and misalignment of the relevant inclinometer inside the model is checked even under load applied to it. Special care was also given to the application of the transition band classically used when testing at a chord Reynolds number of 5 million. Performing this work in close cooperation with the NTF experts minimised the risk for later mismatches in the results originated by this sensitive item.

NTF和Ames 11英尺风洞均使用跨音速壁面干扰修正系统（TWICS），以提供由于测试段边界存在而产生的阻塞和迎角修正。TWICS及其前身壁面干扰修正系统（WICS）是由美国国家航天局（NASA）艾姆斯研究中心（Ames Research Center）的Ulbrich等人作为Hackett壁面特征方法的修改和扩展而开发的。TWICS是WICS的增强版本，可处理跨音速风洞中常见的通风边界条件。该方法被选择在NTF上实施（参见Iyer等人），旨在标准化各美国国家航天局中心之间的壁面干扰修正方法。TWICS基于一种带有普朗特-格劳厄特（Prandtl-Glauert）可压缩性模型的线性化势流方法，该方法固有地假设在测试件近场区域与壁面近场区域之间的测试段中，存在一部分流场是空测试段流场的线性扰动。

Before facilities like NTF and ETW went into operation engineers were convinced of the rigidity of wind tunnel models not suffering remarkable deformations generated by aerodynamic loads especially present in pressurised facilities. Using the unique capabilities of these tunnels for establishing identical Reynolds numbers at different pressure or better q/E levels the opposite could be proven. Nowadays, the correct assessment of the wing shape under load is mandatory for all comparisons to CFD results. Starting with the developments of appropriate measurement systems with a Moirée tool today, ETW may operate 4 systems in parallel, e.g. for monitoring the shape of the main wing and all high lift components of a half-model. The Stereo Pattern Tracking systems (SPT) are capable of monitoring the shift in space of markers pasted on the lower wing surface. In the test campaign reported here one system was looking on the main wing with 58 frames/sec while a second one monitored unsteady HTP movements with 386 frames/sec.

该方法使用扣除皮重后的壁面压力特征，即模型安装状态与空测试段之间的差值，以及一个归一化扰动速度数据库，该数据库使用针对给定壁面边界条件数学表示计算出的单位奇点解，并结合测试件的几何信息。对壁面压力特征进行扣除是为了消除空风洞边界层（boundary layer）和浮力的一阶效应，假设其仅包含固体和尾流阻塞，并假设由于测试件存在而导致的测试段壁面边界层位移厚度的二阶附加变化可忽略不计——这一假设在马赫数（Mach number）接近1时会被破坏，因为此时横流的各个方面更为关键。测试件使用适当加权的偶极子链进行建模，以表示机身、尾流和支承系统（support system）。通常沿升力面四分之一弦长分布的线偶极子被用于模拟升力的影响。线偶极子的强度由天平测得的升力确定。从这些奇点产生的壁面特征中减去扣除皮重后的壁面特征，仅留下阻塞特征。该剩余特征用于确定固体和尾流阻塞奇点的强度。

Both the NTF and the Ames 11-ft wind tunnels use the Transonic Wall Interference Correction System (TWICS) to provide blockage and incidence corrections due to the presence of the test section boundary. TWICS and its predecessor, the Wall Interference Correction System (WICS), were developed at the NASA Ames Research Center by Ulbrich et al.as a modification and extension of the Hackett wall signature method. TWICS is an enhanced version of WICS that handles ventilated boundary conditions, typically seen in transonic wind tunnels. This method was chosen to be implemented at the NTF, see Iyer et al.,in an effort to standardize the wall interference correction methodology across NASA centers. TWICS is based on a linearized potential flow method with a Prandtl-Glauert compressibility model which inherently assumes that there is a portion of flow in the test section between the near-field region of the test article and the near-field region of the wall that is a linear perturbation of the empty test section flow field.

尽管两个设施都使用TWICS，但实现方式并不相同。差异在于壁面边界条件的制定和应用方式。Ulbrich对艾姆斯11英尺风洞的挡板开槽（即多孔）壁面边界条件进行了校准和验证。Walker对NTF中的纵向开槽壁面边界条件进行了校准和验证。艾姆斯11英尺风洞使用离散壁面公式，即在挡板槽中应用边界条件；而NTF使用均匀壁面公式，这更像是对通风壁面边界效应的平均表示。目前正在进行评估将NTF壁面边界条件建模为离散形式的影响的工作。预计将NTF改为离散公式可能会导致迎角修正量减小。本网站上提供的数据是使用各设施各自的TWICS实现进行修正的。

The method uses a tared wall pressure signature, which is the difference between the model installed condition and the empty test section, a database of normalized perturbation velocities using unit singularity solutions computed for a given mathematical representation of the wall boundary condition, and geometric information from the test article. Tareing of the wall pressure signature is performed to remove first order effects of the empty tunnel boundary layer and buoyancy, is assumed to contain only the solid and wake blockage, and is also assumed that the additional second order change in the test-section-wall boundary layer displacement thickness due to the presence of the test article is negligible—an assumption that is violated by flow near a Mach number of unity where aspects of the crossflow are more critical. The test article is modeled with an appropriately weighted point doublet chain to represent the fuselage, wake, and support system. Line doublets, typically distributed along the lifting surface quarter-chord, are used to simulate the effect of lift. The strengths of the line doublets are determined using the measured lift from the balance. The resulting wall signature from these singularities is subtracted from the tared wall signature, leaving only the blockage signature. This remaining signature is used to determine the strengths of the solid and wake blockage singularities.

在艾姆斯11英尺风洞的测试期间，在机翼/机身、机翼/机身/尾宿（Tail）=0和机翼/机身/尾宿=+2的构型上获得了压力敏感漆（PSP）数据。在此页面上，您将找到这些PSP数据的摘要、PLOT3D格式的数据本身，以及获取数据的三种构型的网格。下面还提供了详细介绍此次测试期间PSP过程的论文链接：

Although both facilities use TWICS, the implementations are not identical. The differences occur in how the wall boundary conditions are formulated and applied. Ulbrichperformed a calibration and validation of the baffled, slotted (i.e. porous) wall boundary condition for the Ames 11-ft wind tunnel. Walker calibrated and validated the longitudinal slotted wall boundary condition in the NTF. A discrete wall formulation, where the boundary condition is applied in the baffled slot, is used at the Ames 11-ft wind tunnel; whereas, a homogeneous wall formulation, which is more of an averaged representation of the effect of the ventilated wall boundary, is used at the NTF. Work is in progress to assess the impact of modeling the NTF wall boundary condition as discrete. It is anticipated that a change to the discrete formulation of the NTF may lead to a decreased incidence correction. Data presented on this website are corrected using the respective implementations of TWICS at each facility.

机翼/机身构型数据

During the test in the Ames 11′ wind tunnel test PSP data was obtained on the Wing/Body, Wing/Body/Tail=0 and Wing/Body/Tail=+2 configurations. On this page you will find a summary of this PSP data, the data itself in PLOT3D format as well as grids for the three configurations on which data was taken. A link to a paper detailing the PSP process during this test is also given below:

机翼/机身/尾宿=0构型

Wing/Body Configuration Data

机翼/机身/尾宿=+2构型

Wing/Body/Tail=0 Configuration

迄今为止在CRM上进行的一些实验的最终运行日志包含了所有数据，以及描述数据文件中包含内容的页面。

Wing/Body/Tail=+2 Configuration

艾姆斯最终运行日志可在此处获取：CRM Ames Test 216 Run Log。

The final run logs from some of the experiments that have been performed on the CRM thus far contain all of the data as well as a page that describes what is included in the data files.

NTF最终运行日志可在此处获取：

The Ames final run log is available here, CRM Ames Test 216 Run Log.

来自第一次NTF条目的完整力和力矩数据集位于此处：NTF197Data

The NTF final run logs are available here:

若要仅选择特定条件进行下载，请使用此菜单内的搜索工具。

The entire force and moment data set from the first NTF entry is located here, NTF197Data

要下载免费的Adobe Reader，请点击此处。

To only pick certain conditions to download, use the search tool within this menu.

To download the free Adobe Reader please click here.