An accurate calibration method for high pressure vibrating tube densimeters in the density interval (700 to 1600)kg·m−3

摘要: Abstract A calibration procedure of vibrating tube densimeters for density measurement liquids in the intervals (700 to 1600) kg · m−3, (283.15 323.15) K, and (0.1 60) MPa is presented. It based on modelization as a thick-tube clamped at one end (cantilever) whose stress thermal behaviour follows ideas proposed Forced Path Mechanical Calibration model (FPMC). Model parameters are determined using two fluids with densities certified atmospheric pressure (dodecane tetracholoroethylene) third known function (water). applied Anton Paar 512P densimeter, obtaining measurements an expanded uncertainty less than 0.2 kg · m−3 working intervals. This accuracy comes from combination several factors: densimeter behaves linearly interval, both cover that interval they have very low uncertainty, mechanical well characterized by considered model. The main application this method precise high which most procedures inaccurate.