The PSI Real-Time Transient Model (RTTM) is the fundamental component of PSIpipelines. It simulates the hydraulic behaviour and thermodynamics of the flow at each point of the pipeline and compares in real-time the calculated values with the actual data. The system receives measurements from instrumentation (e.g. flow, pressure, temperature, density, etc.) and updates the model on a fixed cycle basis. The calculations include regular solving of hydraulic, thermodynamic and state equations taking into account the properties of the pipeline and fluid, instrumentation and equipment, state variations and the heat exchange with the surroundings.
Based on a complete and accurate mathematical representation the PSIpipelines RTTM represents the pipeline state under any operating condition and provides accurate information to the operator and associated applications. The model is also capable to take wax and drag reduction agents into account. The PSIpipelines RTTM is very robust in handling bad or inconsistent data and ensures that faulty input data will not cause instability or shut-down of the complete system. It contains auto-tuning and self-adaption functions to improve results during pipeline operation and to detect negative drifts that may occur.
Even though the capability of the modelling software is determined by pipeline design and instrumentation, the software itself imposes no limitations on the performance of the overall system. In environments with many different pipelines that transport different fluids and gases, the model is able to handle all pipelines at the same time.
The PSIpipelines Tracking System is another fundamental component and closely integrated with the PSIpipelines Real-Time Transient Model. The Tracking System provides complete linefill information for all associated applications and keeps all data reliable even if a pipeline topology has been changed. With its powerful and proven methods the tracking system covers all requirements for accurate tracking of scrapers, batches, products, densities and temperatures.
The tracking system is able to handle any mixing and splitting point. It uses scraper signals in order to correct automatically their position and generates warnings whenever valve stations are approached. The Tracking System calculates and provides the exact arrival time and velocity of all linefill elements. Operators are informed in good time before a batch arrives at a pump station or pipeline branch.
The PSIpipelines Real-Time Transient Model provides high-resolution realtime hydraulic profiles. These profiles help the operator to identify pressure excursions, liquid dropout, gas breakout or drifts of instrument performance. The system displays various profile plots with both actual and simulated data on the screen including Pipeline Elevation, Pressure, Flow, Temperature, Density, Velocity, Maximum and Minimum Operating Pressure.