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The influence of the physical property parameters of fluids on flow characteristics is one of the main issues in the design, calculation, and use of electromagnetic flowmeters. The degree to which physical properties affect flowmeters varies depending on their working principle. Common electromagnetic flowmeters have certain physical properties that are important: 1 Density ； 2 Viscosity ； 3 Conductivity ； 4 Sound speed ； 5 Thermal conductivity ； 6 Isentropic exponent ； 7 Specific heat capacity ； 8 Chemical Corrosion ； 9 Scaling ； 10 Lubricity ； 11 Phase transition ； 12 Abrasiveness. Why is it necessary to master physical property parameters? What is the use of understanding physical property parameters? 1. Basis for selection The selection of electromagnetic flowmeters relies mainly on two aspects: understanding the performance of the instrument and the physical properties of the medium being measured. The physical property parameters of fluids are an important part of the characteristics of the object under measurement. In field applications, there are many instances where measurements fail to meet the required standards due to insufficient or inaccurate knowledge of the fluid’s physical property parameters. 2. Design calculations for electromagnetic flowmeters In the calculations related to electromagnetic flowmeters, physical property parameters are one of the key factors; to ensure accurate and reliable design calculations, it is essential to have access to accurate basic data. 3. Field Use and Maintenance Changes in the properties of fluids are one of the main reasons for additional errors in flow measurement during field use. To reduce these additional errors, it is necessary to thoroughly examine the impact of physical property parameters on the characteristics of electromagnetic flowmeters. Some current issues regarding physical property parameters in the instrumentation industry: 1. A lack of online instruments for measuring physical properties; these instruments are of poor quality and have a limited range of applications. To improve the accuracy of flow measurement, it is urgent to develop online instruments for measuring physical properties, so that corrections can be made during the measurement process. Currently, instruments (transmitters) for measuring density and viscosity online are not only technically complex and expensive, but also have a limited range of applications, which prevents their widespread use ； 2. Low accuracy of physical property parameter data, poor reliability, and inconsistent data. The physical property parameter data for fluids used in electromagnetic flowmeters are generally taken from various physical, chemical, and engineering handbooks. Due to the mixed sources of this data, there are inconsistencies among them; moreover, different handbooks are designed for different users, which makes it difficult to meet the requirements for high accuracy in flow measurement as well as the need for precise accuracy values. For many fluids, there is insufficient data on their physical properties, or such data is entirely absent. This is especially true for fluids with extreme conditions (high pressure, high temperature, low temperature, high vacuum, etc.) and multiphase fluids (fluid mixtures), whose physical property parameters not only have poor reliability but are sometimes completely lacking ； 3. Lack of specialized property manuals Given the impact of fluid property parameters on the measurement accuracy of electromagnetic flowmeters, standards have been established for a few such parameters abroad. However, it is practical to compile a dedicated manual for the property parameters related to flow measurement, as this would provide comprehensive and unified data. Especially with the widespread use of computers, charts alone are no longer sufficient to represent material properties, and there is an urgent need to provide various calculation formulas for easy use. For more information, please visit the company’s official website at http://www.yb1518.com/. Please keep this link when reproducing the content! http://www.yb1518.com/UploadFiles/2012717174126829.jpg