Leveraging the state of art know-how and technological edge of its engineering staff, CST has developed a structured approach to the compressor design (aerodynamic, mechanical and rotordynamic) based on complete compressor stage simulation and performance assessment.
This approach results in outstanding quality both in New Units design and in Field Support activities (CM&U, troubleshooting & failure analysis, rehabilitation and upgrading).
Tender Stage Selection
CST optimizes Thermodynamic Design, starting from standardized compression stages (2D or 3D impellers, vaneless or vaned diffusers, bladed return channels or volutes), to be adapted to customer requirements. In this way, we select the best stage configuration, matching the specific application and getting the overall compressor performance curves, from choke to surge as a function of speed or IGV position.
Real gas equations of state are used in order to guarantee accurate curves.
Once the machine configuration has been selected, the aerodynamic design of the rotating and stationary components is defined. All geometries (impellers, diffusers, volutes or return channels) are optimized to maximize efficiency and flow rangeability.
For customized designs, we use 3D model CFD simulations to obtain accurate characterization of velocity fields, pressure distribution and sources of losses. CFD simulation also provides a performance verification of design and off-design conditions, determining compression efficiency and power consumption.
We use FEA to characterize structural properties, identifying local stress levels in the worst operating conditions (e.g. overspeed test).
By means of Lumped Parameter Models, we can also carry out the rotordynamic study of rotating parts (according to API std), focusing on:
- lateral analysis (natural frequencies & mode shapes, response to unbalance)
- torsional analysis (natural frequencies & mode shapes, torsional forced response)
Typical deliverables of the detailed design engineering are:
- Manufacturing drawings and specifications
- Inspection/testing procedures
- Control and antisurge philosophy
- Dry gas seal system selection and specification (if applicable)
CST supports clients also on project completion and during the whole machine lifecycle, delivering:
- Field supervision throughout the commissioning and startup phase
- Troubleshooting & failure analysis
- Conversion, modification & upgrade services