RTTM-Model Compensated Mass Balance

Model Compensated Mass Balance (MCMB) is the most powerful and most accurate balancing method to detect pipeline leaks. Unlike uncompensated mass balance, the MCMB takes changes in pipeline inventory into account. The calculation of inventory requires product density as a parameter. Density and pipe geometry may vary along a pipeline.

That’s why it is necessary to integrate a density profile which in turn depends on pressure and temperature. The profiles are provided by the RTTM in order to correctly determine the pipeline inventory for steady-state and transient conditions. Finally, the MCMB compares mass changes based on measured data against mass changes based on model data.

The MCMB uses the following data for calculations:

  • Flow meter readings at pipeline inlets and outlets
  • Pipeline geometrical data
  • Topological data
  • RTTM calculated pressure, temperature and density profiles
  • Fluid compressibility
  • Inventory