1.1 本试验方法涵盖了要求和指南，并规定了测量垂直安装在试验箱中的开窗系统稳态热透射比所需的校准程序。本试验方法规定了使用符合试验方法的测量系统进行的必要测量 C1363 用于测定开窗系统的热透射率。 注1: 该测试方法允许测试垂直安装在环绕面板中的突出开窗产品（即花园窗、天窗和屋顶窗）。当前对天窗、屋顶窗和投影产品的研究有望提供可添加到该测试方法下一版本中的额外信息，以便可以水平测试天窗和屋顶窗，或以典型的倾斜屋顶的某个角度进行测试。 1.2 本试验方法是指热透射率， U 在没有太阳辐射和漏气影响的情况下垂直安装的开窗系统。 注2: 本文件中描述的方法也可适用于确定建筑墙体部分以及包含热异常的屋顶和地板组件的热透射比，这些热异常小于热箱计量面积。 1.3 本试验方法描述了如何确定热透射比， U S 在明确规定的环境条件下对开窗产品（也称为试样）进行测试。热透射率也是试验方法中报告的试验结果 C1363 . 如果使用本试验方法仅报告热透射率，则试验报告还必须包括试验期间热室环境条件的详细描述，如所述 10.1.14 . 1.4 出于评级目的，本试验方法还描述了如何计算标准化热透射比， U 装货单 ，可用于比较具有截然不同热室配置的实验室的测试结果，并有助于与使用标准传热系数来确定门窗产品热透射率的计算机程序的结果进行比较。虽然本试验方法规定了两种计算标准化热透射比的方法，但每次试验仅报告一种方法的标准化热透射比结果。一个标准化的热透射比计算程序是校准传递标准（CTS）方法，另一个是面积加权（AW）方法（见第节） 9 这两种方法的进一步描述）。面积加权法要求按照实践中的规定直接测量试样两侧的表面温度 E1423 为了确定试验期间开窗产品的表面传热系数。CTS方法不使用试样上测量的表面温度，而是利用校准数据计算等效表面温度来确定试样表面传热系数。当热透射率， U S ，大于3.4 W/（m） 2. ·K） [0.6 Btu/（小时·英尺） 2. ·°F）]，或当试样的投影表面积与试样任一侧的润湿（即总传热或显影）表面积之比小于0时。 80.否则，应使用CTS方法来标准化热透射比结果。 1.5 讨论了测量热透射比的术语和基本假设。 1.6 以国际单位制表示的数值应视为标准。括号中给出的值仅供参考。 1.7 本标准并非旨在解决与其使用相关的所有安全问题（如有）。本标准的用户有责任在使用前制定适当的安全、健康和环境实践，并确定监管限制的适用性。 1.8 本国际标准是根据世界贸易组织技术性贸易壁垒（TBT）委员会发布的《关于制定国际标准、指南和建议的原则的决定》中确立的国际公认标准化原则制定的。 ====意义和用途====== 4.1 本试验方法详细说明了校准和试验程序以及应用试验方法所需的必要附加温度仪表 C1363 测量垂直安装在热室中的开窗系统的热透射比。 4.2 试样的热透射率受其尺寸和三维几何形状的影响。当推断产品尺寸小于或大于试样时，必须小心。因此，建议按照实践中规定的推荐尺寸对开窗系统进行测试 E1423 或NFRC 100。 4.3 由于温度和表面传热系数条件都会影响结果，因此使用推荐条件将有助于减少在不同条件下进行的试验结果比较所引起的混淆。 在实践中规定了测定门窗系统热透射率的标准试验条件 E1423 和截面 6.2 . 在标准化测试条件下测量的试样性能可能不同于安装在室外建筑物墙壁上的同一开窗产品的性能。标准化测试条件通常代表极端的夏季或冬季设计条件，这可能不同于安装在外墙上的开窗产品通常经历的平均条件。为了进行比较，必须使用校准传递标准（CTS）上的表面传热系数进行校准，这些系数尽可能接近建筑设计的常规接受值； 然而，该程序可在其他条件下用于研究目的或产品开发。 4.4 类似地，希望有一个与安装开窗系统的实际墙壁完全相同的环绕面板。由于北美住宅、商业和工业建筑中有各种各样的开窗系统开口，因此选择典型的围板结构来安装开窗系统试样是不可行的。此外，对于安装在具有热桥的开窗设计和施工中的高阻力开窗系统，通过热桥的相对大量传热将导致通过开窗系统的相对少量传热产生大于预期的误差。 因此，校准转移标准和试样安装在由具有相对较高热阻的材料制成的均质环绕面板中。将试样安装在相对较高的热阻环绕板中，将测试重点放在门窗系统的热性能上。因此，重要的是要认识到，从本试验方法中获得的热透射比结果适用于理想的实验室条件，并且只应用于门窗产品的比较，除非分析中包括由于门窗系统开口的特定设计和施工而可能发生的热桥效应。 4.5 本试验方法不包括确定由于空气通过试样或太阳辐射效应而产生的热流的程序。 因此，获得的热透射比结果并不反映现场安装预期的性能。可以使用该测试方法的结果作为年度能源性能分析的输入，包括太阳能和空气泄漏效应，以更好地估计试样安装在实际建筑物中时的性能。要确定开窗产品的太阳能热增益系数，请参阅NFRC 200。要确定门窗的漏气量，请参阅测试方法 E283年 和 E783 . 4.6 重要的是要认识到热透射比， U S ，第节中确定的值 8. 是该测试方法唯一真实的实验测量结果。“标准化”热透射比值， U 装货单 ，通过第节中描述的校准传递标准（CTS）或面积加权（AW）方法获得 8. 包括根据第节中描述的校准运行结果对热透射比值进行的调整 6. . 标准化热透射比有两个原因；它有助于比较具有不同热室几何形状和配置的不同实验室之间的测试结果，并改进了测试结果与计算机模拟结果之间的比较。由于本试验方法允许的尺寸、几何形状和气候室气流的差异，试验方法 C1363 ，并练习 E1423 ，即使这些实验室在其校准传递标准上测量了相同的表面传热系数，安装在不同实验室的同一试样上的局部表面传热系数也可能存在显著变化。 NFRC进行的实验室间比较表明，如果使用标准化热透射率而不是热透射率进行比较，则这种变化的影响会降低。标准化透热率也是评估和比较开窗系统实验结果与计算机计算透热率的有用工具。之所以这样做，是因为在标准化条件下测试时，当前历史上用于确定热透射比的计算机计算方法（NFRC 100）无法应用试样上存在的实际表面传热系数。这些当前的计算机计算方法假设室内和室外开窗产品表面存在统一的标准化表面传热系数。 虽然下一代计算机模拟程序包括改进的辐射传热算法，该算法生成非均匀表面传热系数，但在将测试结果与计算机建模结果进行比较时，标准化热透射比仍然是一个有用的工具。 4.6.1 重要的是要认识到，由于辐射效应，房间侧或天气侧的温度( t h 和 t c ，可能与各自的房间侧或天气侧挡板温度不同( t b1 和 t b2 分别）。如果房间侧或天气侧的差异超过±1°C（±2°F），则应按照第节中的说明考虑辐射影响 6. 和 9 保持计算的表面传热系数的准确性。 计算高导电试样或突出的开窗产品的辐射交换，如所述 附件A2 这不是一项微不足道的任务。 4.6.2 标准化热透射比的计算假设只有表面传热系数与试验条件下的校准标准值不同。如果标准化校准条件的表面温差不同于测试期间试样上存在的表面温差，则该假设可能无效。目前，校准传递标准的规范规定其热透射率为1.7 W/（m） 2. ·K） [0.3 Btu/（小时·英尺） 2. ·°F）]。因此，在具有类似热透射率的试样上进行标准化热透射率的计算时，产生的误差最小。 4.6.3 需要注意的是，标准化表面传热系数， h h 和 h c 在测试开窗产品之前，使用适当尺寸的校准传递标准（CTS）进行校准，可能与特定试样热箱测试期间存在的表面传热系数不同。开窗系统通常具有框架和窗扇表面，这些表面会引入二维和三维对流传热效应，从而导致不同于统一标准值的可变表面传热系数。因此，试样表面传热系数将不同于在相同条件下测试的无框架、基本平坦校准传递标准获得的传热系数。 在该标准化程序中，假设差异足够小，因此可以使用校准表面传热系数来计算等效试样平均表面温度， t 1. 和 t 2. ，以估算实际试样表面传热系数。必须认识到，这一假设并非适用于所有开窗产品，特别是对于表面传热系数占总热阻主要部分的高传热产品，以及具有显著表面投影的开窗产品（例如，天窗、屋顶窗、花园窗），其中表面传热系数与标准值相差很大。 4.6.4 在这些情况下，重要的是尝试测量试样表面温度分布，然后直接计算试样平均面积加权表面温度， t 1. 和 t 2. . 这种面积加权（AW）方法也存在问题，因为不知道如何放置温度传感器以获得准确的面积加权，尤其是在作为传热扩展表面（即翅片）的高电导率水平表面上。此外，在试样表面放置许多温度传感器将影响这些表面附近的速度场，从而影响表面温度和表面传热系数。

1.1 This test method covers requirements and guidelines and specifies calibration procedures required for the measurement of the steady-state thermal transmittance of fenestration systems installed vertically in the test chamber. This test method specifies the necessary measurements to be made using measurement systems conforming to Test Method C1363 for determination of fenestration system thermal transmittance. Note 1: This test method allows the testing of projecting fenestration products (that is, garden windows, skylights, and roof windows) installed vertically in a surround panel. Current research on skylights, roof windows, and projecting products hopefully will provide additional information that can be added to the next version of this test method so that skylight and roof windows can be tested horizontally or at some angle typical of a sloping roof. 1.2 This test method refers to the thermal transmittance, U of a fenestration system installed vertically in the absence of solar radiation and air leakage effects. Note 2: The methods described in this document may also be adapted for use in determining the thermal transmittance of sections of building wall, and roof and floor assemblies containing thermal anomalies, which are smaller than the hot box metering area. 1.3 This test method describes how to determine the thermal transmittance, U S of a fenestration product (also called test specimen) at well-defined environmental conditions. The thermal transmittance is also a reported test result from Test Method C1363 . If only the thermal transmittance is reported using this test method, the test report must also include a detailed description of the environmental conditions in the thermal chamber during the test as outlined in 10.1.14 . 1.4 For rating purposes, this test method also describes how to calculate a standardized thermal transmittance, U ST , which can be used to compare test results from laboratories with vastly different thermal chamber configurations, and facilitates the comparison to results from computer programs that use standard heat transfer coefficients to determine the thermal transmittance of fenestration products. Although this test method specifies two methods of calculating the standardized thermal transmittance, only the standardized thermal transmittance result from one method is reported for each test. One standardized thermal transmittance calculation procedure is the Calibration Transfer Standard (CTS) Method and another is the Area Weighting (AW) Method (see Section 9 for further descriptions of these two methods). The Area Weighting method requires that the surface temperatures on both sides of the test specimen be directly measured as specified in Practice E1423 in order to determine the surface heat transfer coefficients on the fenestration product during the test. The CTS Method does not use the measured surface temperatures on the test specimen and instead utilizes the calculation of equivalent surface temperatures from calibration data to determine the test specimen surface heat transfer coefficients. The AW shall be used whenever the thermal transmittance, U S , is greater than 3.4 W/(m 2 ·K) [0.6 Btu/(hr·ft 2 ·°F)], or when the ratio of test specimen projected surface area to wetted (that is, total heat transfer or developed) surface area on either side of the test specimen is less than 0.80. Otherwise the CTS Method shall be used to standardize the thermal transmittance results. 1.5 A discussion of the terminology and underlying assumptions for measuring the thermal transmittance are included. 1.6 The values stated in SI units are to be regarded as the standard. The values given in parentheses are provided for information purposes only. 1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.8 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee. ====== Significance And Use ====== 4.1 This test method details the calibration and testing procedures and necessary additional temperature instrumentation required in applying Test Method C1363 to measure the thermal transmittance of fenestration systems mounted vertically in the thermal chamber. 4.2 The thermal transmittance of a test specimen is affected by its size and three-dimensional geometry. Care must be exercised when extrapolating to product sizes smaller or larger than the test specimen. Therefore, it is recommended that fenestration systems be tested at the recommended sizes specified in Practice E1423 or NFRC 100. 4.3 Since both temperature and surface heat transfer coefficient conditions affect results, use of recommended conditions will assist in reducing confusion caused by comparing results of tests performed under dissimilar conditions. Standardized test conditions for determining the thermal transmittance of fenestration systems are specified in Practice E1423 and Section 6.2 . The performance of a test specimen measured at standardized test conditions is potentially different than the performance of the same fenestration product when installed in the wall of a building located outdoors. Standardized test conditions often represent extreme summer or winter design conditions, which are potentially different than the average conditions typically experienced by a fenestration product installed in an exterior wall. For the purpose of comparison, it is essential to calibrate with surface heat transfer coefficients on the Calibration Transfer Standard (CTS) which are as close as possible to the conventionally accepted values for building design; however, this procedure can be used at other conditions for research purposes or product development. 4.4 Similarly, it would be desirable to have a surround panel that closely duplicates the actual wall where the fenestration system would be installed. Since there are such a wide variety of fenestration system openings in North American residential, commercial and industrial buildings, it is not feasible to select a typical surround panel construction for installing the fenestration system test specimen. Furthermore, for high resistance fenestration systems installed in fenestration opening designs and constructions that have thermal bridges, the large relative amount of heat transfer through the thermal bridge will cause the relatively small amount of heat transfer through the fenestration system to have a larger than desirable error. For this reason, the Calibration Transfer Standard and test specimen are installed in a homogeneous surround panel constructed from materials having a relatively high thermal resistance. Installing the test specimen in a relatively high thermal resistance surround panel places the focus of the test on the fenestration system thermal performance alone. Therefore, it is important to recognize that the thermal transmittance results obtained from this test method are for ideal laboratory conditions, and should only be used for fenestration product comparisons unless the thermal bridge effects that have the potential to occur due to the specific design and construction of the fenestration system opening are included in the analysis. 4.5 This test method does not include procedures to determine the heat flow due to either air movement through the specimen or solar radiation effects. As a consequence, the thermal transmittance results obtained do not reflect performances that are expected from field installations. It is possible to use the results from this test method as input to annual energy performance analyses which include solar, and air leakage effects to get a better estimate of how the test specimen would perform when installed in an actual building. To determine the Solar Heat Gain Coefficient of fenestration products, refer to NFRC 200. To determine air leakage for windows and doors, refer to Test Methods E283 and E783 . 4.6 It is important to recognize that the thermal transmittance, U S , value determined in Section 8 is the only true experimental measurement result of this test method. The “standardized” thermal transmittance value, U ST , obtained by either the Calibration Transfer Standard (CTS) or Area Weighting (AW) methods described in Section 8 include adjustments to the thermal transmittance value bases on results from calibration runs described in Section 6 . The standardized thermal transmittance is useful for two reasons; it facilitates comparison of test results between different laboratories with different thermal chamber geometries and configurations, and it improves the comparison between test results and computer simulation results. Due to the differences in size, geometry, and climate chamber air flow permitted by this test method, Test Method C1363 , and Practice E1423 , there can be significant variations in the local surface heat transfer coefficients on the same test specimen installed in different laboratories even though these laboratories measured identical surface heat transfer coefficients on their Calibration Transfer Standards. Inter-Laboratory Comparisons conducted by the NFRC have shown that the effect of this variation is reduced if the standardized thermal transmittance is used for comparison instead of the thermal transmittance. The standardized thermal transmittance is also a useful tool for the evaluation and comparison of experimental results of fenestration systems with computer calculations of the thermal transmittance. that are made because the current Historically, computer calculation methods (NFRC 100) for determining the thermal transmittance were not capable of applying the actual surface heat transfer coefficients that exist on the test specimen while testing at standardized conditions. These current computer calculation methods assumed that uniform standardized surface heat transfer coefficients exist on the indoor and outdoor fenestration product surfaces. Although the next generation of computer simulation programs includes improved radiation heat transfer algorithms, which generate non-uniform surface heat transfer coefficients, the standardized thermal transmittance remains to be a useful tool when comparing test results to computer modeling results. 4.6.1 It is important to recognize that due to radiation effects, the room side or weather side temperature ( t h and t c , respectively), has the potential to differ from the respective room side or weather side baffle temperatures ( t b1 and t b2 , respectively). If there is a difference of more than ±1 °C (±2 °F), either on the room side or weather side, the radiation effects shall be accounted for as described in Sections 6 and 9 to maintain accuracy in the calculated surface heat transfer coefficients. Calculating the radiation exchange for highly conductive test specimens or projecting fenestration products as described in Annex A2 is not a trivial task. 4.6.2 The calculation of the standardized thermal transmittance assumes that only the surface heat transfer coefficients change from the calibrated standardized values for the conditions of the test. This assumption is possibly not valid if the surface temperature differentials for the standardized calibration conditions are different from the surface temperature differential that exists on the test specimen during the test. Currently, specifications for the Calibration Transfer Standard give it a thermal transmittance of 1.7 W/(m 2 ·K) [0.3 Btu/(hr·ft 2 ·°F)]. Accordingly, the calculation of the standardized thermal transmittance produces the least error when performed on test specimens with a similar thermal transmittance. 4.6.3 It is important to note that the standardized surface heat transfer coefficients, h h and h c , as calibrated prior to testing a fenestration product using an appropriately sized Calibration Transfer Standard (CTS) have the potential to differ from the surface heat transfer coefficients that exist during a hot box test on a specific test specimen. Fenestration systems usually have frame and sash surfaces that introduce two- and three-dimensional convective heat transfer effects which result in variable surface heat transfer coefficients, which differ from the uniform standardized values. As a result of this, the test specimen surface heat transfer coefficients will differ from those obtained with the non-framed, essentially flat Calibration Transfer Standard tested under the same conditions. In this standardizing procedure, it is assumed that the differences are small enough so that the calibration surface heat transfer coefficients can be used to calculate equivalent test specimen average surfaces temperatures, t 1 and t 2 , in order to estimate the actual test specimen surface heat transfer coefficients. It is important to recognize that this assumption will not be accurate for all fenestration products, especially for high thermal transmittance products where the surface heat transfer coefficients are a major portion of the overall thermal resistance and also for fenestration products with significant surface projections (for example, skylights, roof windows, garden windows) where the surface heat transfer coefficients are quite different from the standardized values. 4.6.4 In these situations, it is important to attempt to measure the test specimen surface temperature distributions and then calculate directly the test specimen average area weighted surfaces temperatures, t 1 and t 2 . This area weighting (AW) method also has problems in that the placement of temperature sensors to get an accurate area weighting is not known, especially on high conductivity horizontal surfaces that act as heat transfer extended surfaces (that is, fins). In addition, the placement of many temperature sensors on the test specimen surfaces will affect the velocity fields in the vicinity of these surfaces which will affect the surface temperatures and surface heat transfer coefficients.