1.1 该测试方法描述了使用安装在表面上的扁平量具测量垂直于表面的净热通量。传导热通量不是本标准的重点。测试方法涵盖了与绝缘材料相关的导电应用 C518 和实践 C1041 和 C1046 该测试方法所涵盖的传感器都使用垂直于表面的两个平行平面之间的温差的测量来确定与表面交换或从表面交换的热量，以符合傅立叶定律。这些量具的工作原理相同，可在任一方向上进行传热。 1.2 这种测试方法在其应用领域、尺寸和结构上都相当广泛。在后面的部分中详细描述了不同的传感器类型，作为测量从垂直于表面的温度梯度的热通量的一般方法的例子（ 1 ). 2 应用包括辐射和对流传热。该量具具有从航空航天到生物医学工程的广泛应用，测量范围从0.01 kW/m 2 至50千瓦/米 2 量具通常是正方形或长方形，并且在一侧的尺寸从1mm到10cm或更大不等。厚度范围为0.05至3mm。 1.3 以SI单位表示的值应被视为标准。括号中所述的值仅供参考。 1.4 本标准并不旨在解决与其使用相关的所有安全性问题（如果有）。本标准的使用者有责任在使用前建立适当的安全、健康和环境实践并确定法规限制的适用性。 1.5 本国际标准是根据《关于制定国际标准的原则的决定》中确立的国际公认的标准化原则制定的世界贸易组织技术性贸易壁垒（TBT）委员会发布的ide和建议。 ======意义和用途====== 5.1 该测试方法将为测量到达或离开表面位置的净热通量提供指导。为了确定辐射能量分量，需要量具表面涂层的发射率或吸收率，并且应该与周围表面匹配。由于量具的存在而导致的表面潜在的物理和热破坏应最小化并进行表征。对于对流和流向或来自表面的低源温度辐射的情况，重要的是要考虑量具的存在如何改变表面热通量。所需的量通常是在不存在量具的情况下表面位置处的热通量。5.1.1 温度限制由量具材料特性和表面应用方法决定。可测量的热通量范围和时间响应受到量具设计和构造细节的限制。从10 W/m开始的测量 2 至100千瓦/米以上 2 用电流传感器很容易获得。低至10ms的时间常数是可能的，而较厚的传感器可能具有大于1s的响应时间。选择传感器样式和特性以匹配所需应用的范围和时间响应非常重要。 5.2 测量的热通量基于一维分析，在量具表面的表面上具有均匀的热通量。由于量具放置在表面上会引起热破坏，这可能不是真的。韦斯利（ 3 ）和巴巴等人。（ 4 ）分析了量具对表面基板内的热场和传热的影响，并确定一维假设在以下情况下是有效的: 其中: k s = 衬底材料的热导率， R = 量规的有效半径， d ga = 所述组合厚度，以及 k ga = 量具和粘合剂层的有效热导率。 5.3 对流热通量的测量对表面温度的扰动特别敏感。因为传热系数也受到表面温度的任何不均匀性的影响，所以温度随位置的微小变化的影响被进一步放大，如Moffat等人所解释的。（ 2 ）和迪勒（ 5 ).此外，量具表面积越小，对任何表面温度非-均匀性。因此，由压力计引起的表面温度干扰应保持远小于引起热通量的表面与环境温差。这需要量具和安装它的表面之间有一个良好的热路径。 5.3.1 图2 显示了安装在板上的热通量计，计的表面温度为 T s 以及周围板的表面温度 T p 目标是保持量具表面温度尽可能接近板温度，以最小化量具的热破坏。这要求量具和粘合剂的热阻沿着热路径最小化 T s 和 T p 一个有用的标准是保持 这意味着与对流热阻相比，量具的热阻较小。施加热通量的阶跃变化值由下式表示 q ss 得到的时间常数表征了一阶传感器响应。

1.1 This test method describes the measurement of the net heat flux normal to a surface using flat gages mounted onto the surface. Conduction heat flux is not the focus of this standard. Conduction applications related to insulation materials are covered by Test Method C518 and Practices C1041 and C1046 . The sensors covered by this test method all use a measurement of the temperature difference between two parallel planes normal to the surface to determine the heat that is exchanged to or from the surface in keeping with Fourier’s Law. The gages operate by the same principles for heat transfer in either direction. 1.2 This test method is quite broad in its field of application, size and construction. Different sensor types are described in detail in later sections as examples of the general method for measuring heat flux from the temperature gradient normal to a surface ( 1 ). 2 Applications include both radiation and convection heat transfer. The gages have broad application from aerospace to biomedical engineering with measurements ranging form 0.01 kW/m 2 to 50 kW/m 2 . The gages are usually square or rectangular and vary in size from 1 mm to 10 cm or more on a side. The thicknesses range from 0.05 to 3 mm. 1.3 The values stated in SI units are to be regarded as the standard. The values stated in parentheses are provided for information only. 1.4 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. 1.5 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 ====== 5.1 This test method will provide guidance for the measurement of the net heat flux to or from a surface location. To determine the radiant energy component the emissivity or absorptivity of the gage surface coating is required and should be matched with the surrounding surface. The potential physical and thermal disruptions of the surface due to the presence of the gage should be minimized and characterized. For the case of convection and low source temperature radiation to or from the surface it is important to consider how the presence of the gage alters the surface heat flux. The desired quantity is usually the heat flux at the surface location without the presence of the gage. 5.1.1 Temperature limitations are determined by the gage material properties and the method of application to the surface. The range of heat flux that can be measured and the time response are limited by the gage design and construction details. Measurements from 10 W/m 2 to above 100 kW/m 2 are easily obtained with current sensors. Time constants as low as 10 ms are possible, while thicker sensors may have response times greater than 1 s. It is important to choose the sensor style and characteristics to match the range and time response of the required application. 5.2 The measured heat flux is based on one-dimensional analysis with a uniform heat flux over the surface of the gage surface. Because of the thermal disruption caused by the placement of the gage on the surface, this may not be true. Wesley ( 3 ) and Baba et al. ( 4 ) have analyzed the effect of the gage on the thermal field and heat transfer within the surface substrate and determined that the one-dimensional assumption is valid when: where: k s = the thermal conductivity of the substrate material, R = the effective radius of the gage, δ ga = the combined thickness, and k ga = the effective thermal conductivity of the gage and adhesive layers. 5.3 Measurements of convective heat flux are particularly sensitive to disturbances of the temperature of the surface. Because the heat transfer coefficient is also affected by any non-uniformities of the surface temperature, the effect of a small temperature change with location is further amplified, as explained by Moffat et al. ( 2 ) and Diller ( 5 ). Moreover, the smaller the gage surface area, the larger is the effect on the heat transfer coefficient of any surface temperature non-uniformity. Therefore, surface temperature disruptions caused by the gage should be kept much smaller than the surface to environment temperature difference causing the heat flux. This necessitates a good thermal path between the gage and the surface onto which it is mounted. 5.3.1 Fig. 2 shows a heat-flux gage mounted onto a plate with the surface temperature of the gage of T s and the surface temperature of the surrounding plate of T p . The goal is to keep the gage surface temperature as close as possible to the plate temperature to minimize the thermal disruption of the gage. This requires the thermal resistance of the gage and adhesive to be minimized along the thermal pathway from T s and T p . A useful criterion is to keep the value of which means that the thermal resistance of the gage is small compared to the convective thermal resistance. The value of the step change in imposed heat flux is represented by q ss . The resulting time constant characterizes the first-order sensor response.