Question

LE 5.50 The pressure in a large vessel is to be maintained at some set pressure for a series of tests. A compressor is to supply air through a regulating valve that is set to open and close at thc set pressure. A dial gauge (resolution: 1 psi; uncertainty: 0,5 psi) is used to monitor pressure in the vessel. Thiny tri- als of pressurizing the vessel to a set pressure of 50 psi are attempted to estimate pressure controllability and a stan- dard deviation in set pressure of 2 psi is found. Estimate the uncertainly to be expected in the vessel sce pressure. Compare to the uncertainty in estimating the average set It pressure. BANGAN H ABER RSS OLAR UITS

Answer 1

Solution Given data Vessel to Set pressure pressure = 50 psi Standard deviation of pressure .: = 2 psi . n = 30 . . . razpsi Erros standard of is Estimate Evrovo S 230 = 0-365 uncertainity Errou is given by Sange of value likely to Encloe the true value Measured value t uncertainity A we have (50 ± 0.365) A uncertainity in Estimating ang set pressure to (50 + 015)