Turbomachinery simulation for performance, blade loading and stage design
Predict the head or pressure ratio, efficiency and blade loading of a pump, compressor, turbine or fan across its operating range, and see which blade and passage changes move the curve where you need it.
Turbomachinery design is a balance of incidence, diffusion and loading. Blade angles that suit the design point can separate at part load, a vaned diffuser that recovers pressure well at one flow can choke at a higher one, and a pump impeller that meets its head may cavitate as suction pressure falls. A prediction at a single point says little about how the machine behaves across the range it will actually run.
More about turbomachinery simulation
Turbomachinery CFD solves the flow through the inlet, rotor, stator or volute and outlet at a series of operating points, building up the characteristic curve. Alongside head or pressure ratio and efficiency, it shows blade-to-blade loading, incidence at the leading edge, separation, secondary flows and tip leakage, and for pumps the regions where local pressure falls below vapour pressure. Those details explain the shape of a curve and point to the change that will improve it.
A full operating map can cover several speeds, with alternative blade counts, angles and passage shapes compared on the same basis. The study ends with improved geometry and the blade loads that go with it.
Typical machines: process and water pumps, centrifugal blowers and compressors, small hydro and radial turbines, expanders, axial fans and cooling fans.
What a turbomachinery study tells you
Where does the machine sit on its curve?
Head or pressure ratio, power and efficiency across flow rate and speed, with the best efficiency point located.
How is each blade loaded?
Pressure distribution along each blade from hub to tip, showing where loading is too high or too low and where it could be redistributed.
Is there a cavitation risk?
Regions where static pressure falls below vapour pressure at the suction conditions and NPSH available on your installation, and how inlet design changes them.
What happens away from the design point?
Incidence and separation at part load and overload, which show where stall, recirculation or choke will limit the usable range.
Are the stages matched?
In multistage machines, how the flow leaving one stage suits the next, and whether one stage is doing more than its share of the work.
What we model
Pumps
Centrifugal, mixed-flow and axial pumps, with impeller, diffuser or volute, and the suction and discharge pipework where it affects performance.
Compressors and blowers
Centrifugal and axial machines with compressible flow, giving pressure ratio, efficiency and behaviour towards choke and low flow.
Turbines and expanders
Hydraulic turbines, and radial or axial turbines and expanders running on air or gas, giving power output, efficiency and flow capacity.
Fans
Axial and centrifugal fans, with blade angle, solidity and hub-to-tip ratio studied against pressure rise and efficiency.
Blade and passage design
Blade angles, camber, thickness, count and passage area varied to shift the curve or move the best efficiency point.
Stage and multistage flow
Rotor and stator rows solved together, steady or transient, so the interaction between rows is part of the prediction.
Blade loads for structure
Fluid pressures and centrifugal loads passed to stress, vibration and fatigue analysis of blades, impellers and discs.
Before you start
What to send us
- Blade, impeller, volute or casing geometry (STEP or native), or the blade design parameters
- Design point and the operating range to cover
- Rotational speed, or the range of speeds
- Working fluid and inlet conditions, including NPSH available for pumps
- Performance targets, or the curve the machine has to meet
- Running clearances and any manufacturing limits on the blades
Can you produce a full performance map?
Yes. The map is built from a range of flow rates and, where needed, several speeds, giving head or pressure ratio, power and efficiency across it.
How do you assess cavitation?
We locate the regions where pressure falls below vapour pressure at your suction conditions, which shows where cavitation will start and how blade and inlet changes move it.
Can you start from a blade specification rather than CAD?
Yes. The blade and passage geometry can be built from your design parameters, so the study can start before any CAD exists.
Do you include the volute and pipework?
Wherever they affect the result. A volute or an inlet bend can change impeller performance noticeably, so the flow path is modelled as installed when it matters.
Send us your machine
