Validation of a large-capacity water flow standard system from (0.01 to 2000) m3/h at KRISS

Simulation results of Monte Carlo methods with 1 × 10 4 iterations based on ISO 5168, GUM and EA-4/02 follow a Gaussian probability density function. Monte Carlo method based on WGFF guidelines provides similar results and validates the experimental results. The combination of GUM and EA-4/02 can provide a theoretical basis for comparison calibrations. • ISO 5168, GUM, and EA-4/02 can provide a basis for both absolute and comparison calibrations. • WGFF guidelines can provide a framework to deal with reported uncertainty. • Monte Carlo methods validate the measurement uncertainty of a water flow standard system. Water is crucial in a modern society, with potable water provided for households, coolant water for electrical power plants, and as a solvent for the pharmaceutical and biochemical industries. The dynamic range of water flow measurements has grown to meet the needs from these industrial sectors. At present, the lowest flow rate is 0.2 μg/s, while the highest flow rate is 20 kt/s for industrial applications. This study explains the development of a water flow standard system at KRISS in South Korea. It has a flow range of 2.8 g/s (0.01 m 3 /h) to 0.56 t/s (2000 m 3 /h) with measurement unc_121074ertainty as large as 0.06 % ( k = 2). A gravimetric system with a weighing tank and a flow diverter is constructed and evaluated according to the ISO 4185, GUM, and EA-4/02 specifications. Monte Carlo methods are applied to validate the measurement uncertainty. Using Monte Carlo methods ensures the equivalence of ISO 5168 with GUM and EA-4/02.