Measurement of pressure

摘要: This chapter briefly discusses pressure management; there are three categories of measurement: absolute pressure, gauge and differential pressure. Absolute is the difference between at a particular point in fluid zero that is, complete vacuum. A barometer one example an gauge, because height column mercury measures atmospheric “zero” Torricellian vacuum exists above column. When pressure-measuring device unknown local measurement known as There basic methods for measuring The simplest method involves balancing against produced by liquid density. second allowing to act on area resultant force either directly or indirectly. third elastic member (of area) stress strain.