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A heat flux sensor is a transducer that generates an electrical signal proportional to the total heat rate applied to the surface of the sensor. The measured heat rate is divided by the surface area of the sensor to determine the heat flux. The heat flux can have different origins; in principle convective, radiative as well as conductive heat can be measured. Heat flux sensors are known under different names, such as heat flux transducers, heat flux gauges, heat flux plates. Some instruments that actually are single-purpose heat flux sensors like pyranometers for solar radiation measurement. Other heat flux sensors include Gardon gauges〔R.Gardon, "An instrument for the direct measurement of intense thermal radiation", Rev. Sci. Instrum., 24, 366-370, 1953.〕 (also known as a circular-foil gauge), thin-film thermopiles,〔T.E. Diller, Advances in Heat Transfer, Vol. 23, p.297-298, Academic Press, 1993.〕 and Schmidt-Boelter gauges.〔C.T. Kidd and C.G. Nelson, "How the Schmidt-Boelter gage really works," Proc. 41st Int. Instrum. Symp., Research Triangle Park, NC: ISA, 1995, 347-368〕 In SI units, the heat rate is measured in Watts, and the heat flux is computed in Watts per meter squared. == Usage == Heat flux sensors are used for a variety of applications. Common applications are studies of building envelope thermal resistance, studies of the effect of fire and flames or laser power measurements. More exotic applications include estimation of fouling on boiler surfaces, temperature measurement of moving foil material, etc. The total heat flux is composed of a conductive, convective and radiative part. Depending on the application, one might want to measure all three of these quantities or single one out. An example of measurement of conductive heat flux is a heat flux plate incorporated into a wall. An example of measurement of radiative heat flux density is a pyranometer for measurement of solar radiation. An example of a sensor sensitive to radiative as well as convective heat flux is a Gardon or Schmidt–Boelter gauge, used for studies of fire and flames. The Gardon must measure convection perpendicular to the face of the sensor to be accurate due to the circular-foil construction, while the wire-wound geometry of the Schmidt-Boelter gauge can measure both perpendicular and parallel flows. In this case the sensor is mounted on a water-cooled body. Such sensors are used in fire resistance testing to put the fire to which samples are exposed to the right intensity level. There are various examples of sensors that internally use heat flux sensors examples are laser power meters, pyranometers, etc. We will discuss three large fields of application in what follows. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Heat flux sensor」の詳細全文を読む スポンサード リンク
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