Denmark-Kgs. Lyngby: Laboratory, optical and precision equipments (excl. glasses)
Voluntary ex ante transparency notice
Section I: Contracting authority/entity
Main address: http://www.dtu.dk
Section II: Object
Procurement of FlowMaster Shake-the-Box and Stereo-PIV System for Fine-Scale Flow Measurements
DTU wish to procure a system that is capable of controlling acquisition and processing images from up to simultaneously 6 high speed cameras into volumetric Lagrangean (particle tracking) and Eulerian (correlation based) velocity fields, including the possibility to estimate pressure from the measured velocity fields. The system must be able to fully automatically perform acquisition, data transfer and distributed processing (on a separate, existing, server) and traceable structuring of the data, once the process has been defined. From both a hardware and a software point of view, it is imperative to be able to program, acquire and process variations in the time between individual recordings, since various accelerating flows will be measured using the acquired system.
DTU Mechanical Engineering wishes to procure a system that is capable of controlling acquisition and processing images from up to simultaneously 6 high speed cameras into volumetric Lagrangean (particle tracking) and Eulerian (correlation based) velocity fields, including the possibility to estimate pressure from the measured velocity fields.
— the system must be able to fully automatically perform acquisition, data transfer and distributed processing (on a separate, existing, server) and traceable structuring of the data, once the process has been defined,
— from both a hardware and a software point of view, it is imperative to be able to program, acquire and process variations in the time between individual recordings, since various accelerating flows will be measured using the acquired system,
— high spatial resolution (seeding particle density of >0.05 particles per pixel) and a well-documented high accuracy based on self-correction from the measured images in the volumetric calibration with the ability of self-correction are also imperative.
Software options: customized user interface, remote interface and distributed processing for the acquisition. GPU package for analysis and a software module for pressure estimation.
Hardware options: high speed cameras, scheimpflug mounts, lenses, camera filters and laser optics. A laser timing stabilizer, helium filled soap bubble seeding system, additional translation systems and plates for calibration as well as possibility for hardware registration of cameras.
The EU-project is financed by the European Research Council in the form of a Starting Grant. The objective is to measure stationary and accelerating turbulent jets to test the range of validity of the classical theory of turbulence as stated by Richardson and Kolmogorov. The project is thus of a fundamental research character and involves high-quality measurements.
Section IV: Procedure
LaVision is the only contractor that is able to provide a system that fulfills the unique combination of required specifications:
— LaVision can unlike its competitors, provide measurement systems that are able to fully control and automate measurements of a time-varying flow, including data handling and processing, once the measurement process has been setup and defined. This includes control and automation of acquisition, data transfer and cluster based processing of the measurements into 3D Lagrangean particle tracks and Eulerian correlation based 3D-3C ve-locity fields, respectively,
— the LaVision software DaVis includes programmable parameter recording for varying the time between individual snapshots across a measurement using a programmable timing unit. A laser timing stabilizer can correct for laser timing errors during image acquisition. Recording at variable framerates within one recording cycle (so-called dual rate recording) is also supported in DaVis. Further, DaVis can correct for the variable delays in the processing,
— the DaVis processing software is unique in the well-published high achievable recorded seeding densities it can process successfully into accurate particle tracking and correlation based velocity fields, respectively:
—— the well-established (>10 years in the community) patented Tomographic Particle Image Velocimetry algorithm (EP 1 517 150 B1) is a well-proven technique that can retrieve volumetric data from densely seeded flows (>0.1 particles per pixel),
—— the patented (EP 3 004 898) volumetric Lagrangian Particle Tracking algorithm, Shake-the-box (STB), can retrieve volumetric particle tracking data from densely seeded flows (> 0,05 particles per pixel). The patented iterative 3D particle reconstruction technique (EP 2 344 894) used with the STB algorithm allows for measurements with such high spatial seeding densities, that it distinguishes the software from the competition. Furthermore, the iterative particle reconstruction allows STB to be used with 2- and 4-pulse data with high seeding density, which reduces significantly the cost of the laser/light source and provides a high flexibility on the measurement possibilities using the same hardware,
— the patented (EP 1 926 049 B1) volumetric self-calibration that produces a self-correction using disparity maps of the acquired images (calibration error <0.1 pixel) is the gold standard with respect to calibration accuracy. This volumetric self-calibration is used for STB as well as for Tomographic measurements,
— the software also comes with a unique option (module) for estimating average pressure fields and a pseudo Lagrangean approach for instantaneous pressure reconstruction. For the particle tracks from STB measurements (regardless of the distribution of particles in the measurement domain), a data assimilation-based technique called Fine-Scale Reconstruction (VIC#) is available in the DaVis software, for firstly ensuring that the measured flow adheres to the flow governing equations and intrinsically, pressure evaluation from these results.
These methods are well-documented and well-accepted in the scientific literature.
A complete system for flow measurements from a single supplier is necessary to ensure a functional assembled system and traceable service and insurance conditions.
Section V: Award of contract/concession
Internet address: www.lavision.com
Section VI: Complementary information
Internet address: http://www.klfu.dk
Internet address: http://www.kfst.dk
Information on certificates required in public procurement in the EU