QBlade Documentation
QBlade 1 is a state of the art multi-physics code, covering the complete range of aspects required for the aero-servo-hydro-elastic simulation of horizontal, or vertical axis wind turbines. This software, developed since 2010, is realized as a modular implementation of highly efficient multi-fidelity aerodynamic, structural dynamic and hydrodynamic solvers in a modern, object oriented C++ framework.
We leverage the current computer architecture by thoroughly utilizing CPU (via OpenMP) and GPU (via OpenCL) parallelization techniques for a high numerical performance. QBlade is a platform independent software, and can be deployed on workstations or clusters running Windows, Unix or MacOS based operating systems. The software is equipped with an intuitive graphical user interface that aids the user during the whole wind turbine design process. All turbine and simulation details are readily available to be accessed and modified in a logical well-structured and tested interface. Simulation results are presented in dynamic graphs that give insight into every simulation detail. Simulations and turbine designs are fully rendered in real time to aid with the comprehension and evaluation of our complex multi-physics models. QBlade enabled the serialization of the complete model data, setup and results into project files to enable simple sharing and collaboration of complex simulation and turbine design projects. The Community Edition of QBlade (QBlade-CE) is freely available under the Academic Public License, while the Enterprise Edition (QBlade-EE) is available under a Commercial License.
QBlade uses a highly optimized and thoroughly validated Lifting Line Free Vortex Wake Method for its aerodynamic calculations. Instead of approximating the wake aerodynamics with a steady-state momentum balance (BEM), the rotor wake is explicitly modeled through Lagrangian vortex elements. This results in a more accurate and detailed spatial and temporal representation (see Marten et al.2) of the rotor induction, when compared to BEM approaches, and fully resolves the velocity distribution behind the rotor. This allows to assess wind turbine wake interaction, accurately accounts for the aerodynamics of oscillating floating wind turbine structures and explicitly resolves unsteady vertical axis wind turbine wake dynamics (see Balduzzi et al.3). As an alternative with lower computational demand the aerodynamics of horizontal-axis wind turbines can be simulated using an unsteady polar-BEM implementation (see Madsen et al.4).
The structural dynamics are modeled in a true multi-body formulation. The sub components of the multi-body model are made up of rigid- or flexible nonlinear Euler beam elements in a corotational formulation. For floating offshore simulations we have integrated cable elements in the absolute nodal coordinate formulation (ANCF) which meet the requirements to effectively model the nonlinear dynamics of complex mooring systems. Both bottom-fixed and floating offshore wind turbine systems can be modeled.
The hydrodynamic loads on the wind turbine’s substructure are calculated either via the potential flow theory, the Morison equation based strip theory or a user defined combination of the two. The integrated potential flow approach also includes the higher order slow drift forces obtained from quadratic transfer functions. QBlade integrates with potential flow data from common software such as the WAMIT, NEMOH or similar toolboxes.

Fig. 1 Different wind turbine types modelled with QBlade.
- QBlade Documentation
- Theory Guide
- User’s Guide
- General GUI Functionality
- Data Structure, Import & Export
- Coordinate Systems
- HAWT, VAWT and PROP Design Modes
- Airfoil Generation and Import
- Airfoil Analysis and Polar Generation
- Polar Extrapolation
- Blade and Rotor Design
- Blade and Rotor BEM Simulation
- Wind Turbine Design
- Overview
- General Turbine Parameters
- Aerodynamic Turbine Design
- Structural Turbine Design
- Main Definition File
- VAWT Specific Parameters
- Loading Data and Sensor Locations
- Blade, Strut and Tower Structural Data Tables
- Structural (Rayleigh) Damping
- Blade / Strut Structural Data Table Columns
- Tower / Torquetube Structural Data Table Columns
- Cable Definition File
- Cross Sectional Blade Coordinate System
- Substructure Design
- Substructure Overview
- Modeling Options for an Offshore Substructure
- Keywords and Tables
- General Topology of a Substructure
- Substructure Joints
- Substructure Elements
- Substructure Members
- Substructure Constraints
- The Transition Piece
- Lumped Mass, Inertia and Hydrodynamic Forces
- Cable Elements and Ground-Fixing
- Nonlinear Spring and Damper Constraints
- Hydrodynamic Modeling of a Substructure
- Morison Equation-Related Parameters
- Linear Potential Flow-Related Parameters
- Miscellaneous Substructure Parameters
- Defining Sensors Locations
- Exemplary Substructure File
- Substructure File Format Changes from QBlade v2.06b
- Substructure Superelements
- Sequential Load Analysis
- Superelement Definitions
- Mass, Stiffness and Damping Matrices
- Superelement Damping
- Time Integration Parameters
- Initial Conditions and DoF
- Assigning Superelements in the Constraint Table
- Assigning Loads to Superelements
- Recommended Timesteps and Modal Frequencies
- Defining Output Sensors for a Superelement
- Exemplary Superelement Definition for the OC4 Jacket
- Marine Hydrokinetic Turbines
- Turbine Controller Libraries
- Turbine Definition ASCII File
- Multi Rotor Turbine Assembly
- Multi Rotor Turbine Assembly ASCII File
- Wind Turbine Simulation
- Simulation Module Overview
- Simulation Definition Dialog
- General Simulation Settings
- Structural Model Initialization
- Wind Boundary Condition
- Turbine Setup
- Rotational Speed Settings
- Turbine Initial Conditions
- Floater Initial Conditions
- Structural Simulation Settings
- Turbine Behavior
- Multi Turbine Simulations
- Turbine Environment
- Wave Boundary Conditions
- Ocean Current Boundary Conditions
- Environmental Variables
- Seabed Modelling
- Stored Simulation Data
- VPML Particle Remeshing
- Modal Analysis
- Ice Throw Simulation
- Simulation Definition ASCII File
- Multi Turbine Simulation Setup
- Multi Turbine Global Mooring System
- Multi-Threaded Batch Analysis
- Multi Turbine Simulation Definition ASCII File
- Extracting Wake Data with Cut-Planes
- Windfield Generation
- Wave Generation
- Design Load Case Generation
- Command Line Interface (CLI)
- Software in Loop Interface (SIL)
- Software in Loop (SIL) Overview
- Quick Start with the SIL Interface in Python
- Interface Function Definitions
- Interface Function Documentation
- Python Example: Running the QBlade Library
- Python Example: Definition of the QBladeLibrary Class
- Matlab Example: Running the QBlade Library
- Matlab Example: Definition of the QBladeLibrary Class
- Changelog
- QBlade 2.0.6.3 beta
- QBlade 2.0.6.2 beta
- QBlade 2.0.6.1 beta
- QBlade 2.0.6.0 beta
- QBlade 2.0.5.2 alpha
- QBlade 2.0.5.1 alpha
- QBlade 2.0.5.0 alpha
- QBlade 2.0.4.9 alpha
- QBlade 2.0.4.8 alpha
- QBlade 2.0.4.7 alpha
- QBlade 2.0.4.6 alpha
- QBlade 2.0.4.5 alpha
- QBlade 2.0.4.4 alpha
- QBlade 2.0.4.3 alpha
- QBlade 2.0.4.2 alpha
- QBlade 2.0.4.1 alpha
- QBlade 2.0.4.0 alpha
- Validation Cases and Examples
- License Info
- 1
D. Marten. QBlade: A Modern Tool for the Aeroelastic Simulation of Wind Turbines. PhD thesis, TU Berlin, 2019. doi:10.14279/depositonce-10646.
- 2
D. Marten, C. O. Paschereit, X. Huang, M. Meinke, W. Schröder, J. Müller, and K. Oberleithner. Predicting wind turbine wake breakdown using a free vortex wake code. AIAA Journal, 58(11):4672–4685, 2020. URL: https://doi.org/10.2514/1.J058308.
- 3
Francesco Balduzzi, David Marten, Alessandro Bianchini, Jernej Drofelnik, Lorenzo Ferrari, Michele Sergio Campobasso, Georgios Pechlivanoglou, Christian Navid Nayeri, Giovanni Ferrara, and Christian Oliver Paschereit. Three-Dimensional Aerodynamic Analysis of a Darrieus Wind Turbine Blade Using Computational Fluid Dynamics and Lifting Line Theory. Journal of Engineering for Gas Turbines and Power, 140(2):022602, 2017. doi:10.1115/1.4037750.
- 4
H. A. Madsen, T. J. Larsen, G. R. Pirrung, A. Li, and F. Zahle. Implementation of the blade element momentum model on a polar grid and its aeroelastic load impact. Wind Energy Science, 5(1):1–27, 2020. URL: https://wes.copernicus.org/articles/5/1/2020/, doi:10.5194/wes-5-1-2020.