idw – Informationsdienst Wissenschaft
Nachrichten, Termine, Experten
Nachrichten, Termine, Experten
In order to carry out research on complex flow processes, the Laser Zentrum Hannover e.V. (LZH) has developed a special sensor that can be used to measure turbulent jet flows.
Turbulence is one of the last phenomena in the field of physics which has is still not understood. However, the rapid development of computer simulations and experimental technology has led to a better understanding turbulence. Phenomena like reducing the turbulence of ships by using micro-bubbles, or increasing the flow rate in pipelines by adding polymers are beneficial, but still not understood completely.
At the LZH, an innovative profile sensor is being developed, which can be used to determine the velocity profile of turbulent shear flows, with high spatial and temporal resolutions. The profile measurements can, for example, provide information on spatial-temporal correlations in turbulent flows. Furthermore, the sensor can be used for a number of technical applications such as flow measurements in high-pressure gas or oil pipelines, or for flow measurements for fuel injection nozzles, on airfoils and aircraft surfaces, or in aircraft turbo-engines.
The research work is in cooperation with the Physikalisch-Technische Bundesanstalt (PTB) in Braunschweig (Dr. H. Müller), and is supported by the Deutsche Forschungsgemeinschaft (DFG).
Contact Person:
Laser Zentrum Hannover e.V. (LZH)
Michael Botts
Hollerithallee 8
D-30419 Hannover
Tel.: +49 511 2788-151
Fax: +49 511 2788-100
E-Mail: bt@lzh.de
http://www.lzh.de
The Laser Zentrum Hannover e.V. (LZH) carries out research and development in the field of laser technology and is supported by the Ministry of Economic Affairs, Labour and Transport of the State of Lower Saxony (Niedersächsisches Ministerium für Wirtschaft, Arbeit und Verkehr).
Sorry...there was a mixup in the text. Here is the correct text concerning the slab laser.
New Slab Laser for flexible and fast 3-D Laser Cutting
New solid-state lasers - so-called slab lasers - can provide output powers up to three kilowatts, with a high beam quality (12 mm*mrad). High beam quality ensures small focus diameters and smaller optics, and greater distances between the processing head and the workpiece, higher process stability and a lower contamination rate for the optics are possible. With these characteristics, it is not surprising that slab lasers are being used more and more for remote welding, for example, a field previously dominated by CO2 lasers.
The Laser Zentrum Hannover e.V. (LZH) has used this laser for, among other things, cutting metals. With an output power of 3 kW and a beam quality of 6 mm*mrad, in combination with a 150 µm fibre, this slab laser provides very small focal diameters. For cutting applications this means a small cutting kerf with high power densities, resulting in high feed rates.
Flexible beam guidance via an optical fibre together with an industrial robot is advantageous for 3-D processing, especially in comparison to CO2 lasers. Due to the high power densities provided by the slab laser thicker materials can also be cut.
Due to the particular wavelength of the slab laser, radiation absorbtion by metals like steel and aluminium are 3-4 times higher than for CO2 lasers. At the LZH, promising investigations on cutting nonferrous metals have been carried out. Although cutting copper is almost impossible using a CO2 laser (due to high reflection), with the slab laser it was possible to cut 1 mm copper plates with a kerf of only 160 µm and a feed rated of 6 m/min. Aluminium (2 mm thick sheets) could be cut at speeds of 12m/min. with a 340 µm kerf.
Contact:
Laser Zentrum Hannover e.V. (LZH)
Michael Botts
Hollerithallee 8
D-30419 Hannover
Tel.: +49 511 2788-151
Fax: +49 511 2788-100
E-Mail: bt@lzh.de
http://www.lzh.de
The Laser Zentrum Hannover e.V. (LZH) carries out research and development in the field of laser technology and is supported by the Ministry of Economic Affairs, Labour and Transport of the State of Lower Saxony (Niedersächsisches Ministerium für Wirtschaft, Arbeit und Verkehr).
Criteria of this press release:
Materials sciences, Mechanical engineering
transregional, national
Research projects, Research results
English
You can combine search terms with and, or and/or not, e.g. Philo not logy.
You can use brackets to separate combinations from each other, e.g. (Philo not logy) or (Psycho and logy).
Coherent groups of words will be located as complete phrases if you put them into quotation marks, e.g. “Federal Republic of Germany”.
You can also use the advanced search without entering search terms. It will then follow the criteria you have selected (e.g. country or subject area).
If you have not selected any criteria in a given category, the entire category will be searched (e.g. all subject areas or all countries).
