Users may wish to measure the flow of steam to help with plant efficiency, energy efficiency, process control or costing purposes. This tutorial considers the characteristics of flowing fluids and the basic requirements for good steam metering practice.
Fluids and Flow
Based on the information given above, determine the maximum and minimum flowrates for turbulent flow with saturated steam at 10 bar g in a 100 mm bore pipeline.
Returning to Example 4.1.5, and inserting values into Equation 4.1.6:
• The mass flow of saturated steam through pipes is a function of density, viscosity and velocity.
• For accurate steam flowmetering, the pipe size selected should result in Reynolds numbers of between 1 x 105 and 1 x 106 at minimum and maximum conditions respectively.
• Since viscosity, etc., are fixed values for any one condition being considered, the correct Reynolds number is achieved by careful selection of the pipe size.
• If the Reynolds number increases by a factor of 10 (1 x 105 becomes 1 x 106), then so does the velocity (e.g. 2.695 m/s becomes 26.95 m/s respectively), providing pressure, density and viscosity remain constant.