Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Optimized Production of Solar Absorbers

26.11.2010
Saving energy for saving energy:
A new laser welding process can be used for saving energy during the manufacturing of solar absorbers, for joining copper tubes to aluminum sheets. Also, the strength of the welding is improved.

A new laser welding process promises both an enormous potential for saving energy and higher welding strengths for the manufacturing of solar absorbers. The main element of this innovative process is a diode laser, which is used to join the copper tubes to the aluminum absorber sheet, instead of using the conventional solid-state laser. The Laser Zentrum Hannover e.V. (LZH) presented first successful results of this project at the end of October at the fair EuroBlech 2010.


The quality of the diode laser welded Cu-Al connection (small section hanging on the solar absorber) impressed the EuroBlech fair visitors.

Solar absorbers stand for energy savings. As the main element in solar collector systems, they use the sun's energy to warm up water and save on heating costs. However, much energy is needed to manufacture the solar absorbers. To weld the copper tubes to the absorber sheets, most manufacturers use two pulsed, solid-state lasers with peak energies up to 6 kW. These flashlamp pumped lasers have a rather low working efficiency, making laser processing very energy intensive, and expensive.

The group "Joining and Separating of Metals" of the Materials and Processing Department of the LZH uses only one 4 kW diode laser for the welding process. This laser not only has a much higher efficiency rate, but it also uses the laser energy better, because copper and aluminum both have higher absorption characteristics for the typical diode laser wavelengths used (800 to 980 nm). A further advantage is that the size of the welding spots can be increased, and wider welding spots mean higher weld stability. It is especially important that the thermal input can be regulated, as an excessive thermal load could damage the absorber coating.

The cooperative project between the Hannoverian laser researchers and the metal-working company Flexxibl GmbH from Brunswick, Germany, is now entering a decisive phase. Following the positive resonance to the welding results shown at the EuroBlech, the partners are now working on developing a new laser processing head for solar absorber welding. In the spring of 2011, they plan on presenting this new diode laser welding head to the absorber industry.

The project (project number KF2186401AB9) is supported by AiF (German Federation of Industrial Research Associations) and runs until the end of February 2011.

Contact:
Laser Zentrum Hannover e.V.
Michael Botts
Hollerithallee 8
D-30419 Hannover
Germany
Tel.: +49 511 2788-151
Fax: +49 511 2788-100
E-Mail: m.botts@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).

Michael Botts | idw
Further information:
http://www.lzh.de

More articles from Process Engineering:

nachricht New manufacturing process for SiC power devices opens market to more competition
14.09.2017 | North Carolina State University

nachricht Quick, Precise, but not Cold
17.05.2017 | Fraunhofer-Institut für Lasertechnik ILT

All articles from Process Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: The pyrenoid is a carbon-fixing liquid droplet

Plants and algae use the enzyme Rubisco to fix carbon dioxide, removing it from the atmosphere and converting it into biomass. Algae have figured out a way to increase the efficiency of carbon fixation. They gather most of their Rubisco into a ball-shaped microcompartment called the pyrenoid, which they flood with a high local concentration of carbon dioxide. A team of scientists at Princeton University, the Carnegie Institution for Science, Stanford University and the Max Plank Institute of Biochemistry have unravelled the mysteries of how the pyrenoid is assembled. These insights can help to engineer crops that remove more carbon dioxide from the atmosphere while producing more food.

A warming planet

Im Focus: Highly precise wiring in the Cerebral Cortex

Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.

The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...

Im Focus: Tiny lasers from a gallery of whispers

New technique promises tunable laser devices

Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...

Im Focus: Ultrafast snapshots of relaxing electrons in solids

Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!

When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...

Im Focus: Quantum Sensors Decipher Magnetic Ordering in a New Semiconducting Material

For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.

Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

“Lasers in Composites Symposium” in Aachen – from Science to Application

19.09.2017 | Event News

I-ESA 2018 – Call for Papers

12.09.2017 | Event News

EMBO at Basel Life, a new conference on current and emerging life science research

06.09.2017 | Event News

 
Latest News

Rainbow colors reveal cell history: Uncovering β-cell heterogeneity

22.09.2017 | Life Sciences

Penn first in world to treat patient with new radiation technology

22.09.2017 | Medical Engineering

Calculating quietness

22.09.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>