620 Ingenieurwissenschaften und zugeordnete Tätigkeiten
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Die Hälfte des Endenergiebedarfs in Deutschland wird zur Deckung des Wärmebedarfs der Wirtschaft und der privaten Haushalte benötigt; überwiegend erzeugt durch Erdgas und Heizöl. Gerade die energetisch nur unzureichend sanierten Einfamilienhausbestände des ländlichen Raumes bergen ein hohes Potenzial für Energieeinsparungs- und Effizienzsstrategien, um zum einen den Klimaschutz zu fördern und zum anderen eine nachhaltige wirtschaftliche Entwicklung des ländlichen Raumes anzustoßen. Die 9. Steinfurter Bioenergiefachtagung zeigt Strategien und Maßnahmen auf, die zeigen, wie eine "Wärmewende im ländlichen Raum" aussehen kann, welche Chancen und Möglichkeiten sie bietet und warum eine "Wärmewende" strategisch unabdingbar für das Gelingen des Generationenprojektes "Energiewende" insgesamt ist. Die Veranstaltung zeichnet den Pfad von konzeptionellen Ideen über Beispiele aus der Praxis bis hin zu zukunftsweisenden technologischen Ansätzen: Wärmekataster Kreis Steinfurt KWK-Modellkommune Saerbeck Wege zum Bioenergiedorf - Praxisbeispiele Technische Voraussetzungen und Möglichkeiten für effiziente Wärmenetze im ländlichen Raum Finanzierungs- und Fördermodelle für eine gelungene Wärmewende
We have developed, manufactured and tested a unimorph deformable mirror for space applications based on piezoelectric actuation. The mirror was designed for the correction of low-order Zernike modes with a stroke of several tens of micrometers over a clear aperture of 50 mm. It was successfully tested in thermal vacuum, underwent lifetime tests, and was exposed to random vibrations, sinusoidal vibrations, and to ionizing radiation. We report on design considerations, manufacturing of the mirror, and present the test results. Furthermore, we discuss critical design parameters, and how our mirror could be adapted to serve recently proposed space telescopes such as HDST and TALC.
Over the past 5 years we have developed a new type of unimorph deformable mirror. The main advantages of this mirror technology are · very low surface scattering due to the use of superpolished glass · excellent coatings, even suitable for high power lasers, can be applied · active diameter of the mirrors can be between 10 mm and 100 mm · large strokes can be achieved even for small mirror diameters · integrated monolithic tip/tilt functionality based on a spiral arm design We have modeled these mirrors by analytical models as well as by the finite element method. This allows us to quickly design new mirrors tailored to specific applications. One example is a mirror for laser applications that has a diameter of 10 mm and can achieve a stroke in defocus mode of 5 μm. The stroke for these mirrors scales as the square of the mirror diameter, meaning that we can achieve, for example, a stroke of 125 μm for a mirror of 50 mm diameter. We will present design criteria and tradeoffs for these mirrors. We characterize our mirrors by the maximum stroke they can deliver for various Zernike modes, under the boundary condition that the Zernike mode has to be created with a certain fidelity, usually defined by the Maréchal criterion.
Trends of changes in waste management and possible optimizations within the waste collection process
(2013)
1. General waste management in Europe 2. Optimization process of disposal logistics a. Technologies (collection systems, vehicles etc.) b. Benchmarking c. Optimization 3. The future and sustainability of waste management
Further space exploration in the far-infrared (FIR) requires larger apertures in order to improve the spatial resolution of captured images. To this purpose, the Thinned Aperture Light Collector (TALC) concept of a deployable annular telescope has been recently developed at CEA, which offers novel perspectives for FIR space missions. The consortium ELICSIR consortium of European institutes and companies has been created to improve the technological readiness level (TRL) of its key systems and components.
Novel unimorph deformable mirror with monolithic tip-tilt functionality for solid state lasers
(2011)
We present a new type of unimorph deformable mirror with monolithic tip-tilt functionality. The tip-tilt actuation is based on a spiral arm design. The mirror will be used in high-power laser resonators for real-time intracavity phase control. The additional tip-tilt correction with a stroke up to 6 μm simplifies the resonator alignment significantly. The mirror is optimized for a laser beam footprint of about 10 mm. We have modeled and optimized this mirror by finite element calculations and we will present design criteria and tradeoffs for this mirrors. The mirror is manufactured from a super-polished glass substrate with very low surface scattering and excellent dielectric coating.
We have developed a new type of unimorph deformable mirror, designed to correct for low-order Zernike modes. The mirror has a clear optical aperture of 50 mm combined with large peak-to-valley Zernike amplitudes of up to 35 μm. Newly developed fabrication processes allow the use of prefabricated super-polished and coated glass substrates. The mirror's unique features suggest the use in several stronomical applications like the precompensation of atmospheric aberrations seen by laser beacons and the use in woofer-tweeter systems. Additionally, the design enables an efficient correction of the inevitable wavefront error imposed by the floppy structure of primary mirrors in future large space-based telescopes. We have modeled the mirror by using analytical as well as finite element models. We will present design, key features and manufacturing steps of the deformable mirror.
We present a novel unimorph deformable mirror with a diameter of only 10 mm that will be used in adaptive resonators of high power solid state lasers. The relationship between applied voltage and deformation of a unimorph mirror depends on the piezoelectric material properties, layer thicknesses, boundary conditions, and the electrode pattern. An analytical equation for the deflection of the piezoelectric unimorph structure is derived, based on the electro-elastic and thin plate theory. The validity of the proposed analytical model has been proven by numerical finite-element modelling and experimental results. Our mirror design has been optimized to obtain the highest possible stroke and a high resonance frequency.
We have developed a new type of unimorph deformable mirror for the correction of low-order Zernike modes. The mirror features a clear aperture of 50 mm combined with large peak-to-valley amplitudes of up to 35 μm. Newly developed fabrication processes allow the use of prefabricated, coated, super-polished glass substrates. The mirror's unique features suggest the use in several astronomical applications like the compensation of atmospheric aberrations seen by laser beacons, low light astronomy, and the use in woofer-tweeter systems. Additionally, the design enables an efficient correction of the inevitable wave-front error imposed by the floppy structure of primary mirrors in future large space telescopes. We have modeled the mirror by using analytical as well as finite element models. We will present design, key features and manufacturing steps of the deformable mirror.
The German Code ATV-M 127-2 published in 2000 for the design of linings to rehabilitate sewers has proved itself a helpful guideline to find the optimum wall thickness of any liner material, e.g. CIPP or stainless steel sleeves. Many rehabilitation projects in different European countries have been performed successfully using this code. The code differentiates between three host pipe states: State I for untight sewers without cracks, state II for sewers with longitudinal cracks but a stable soil pipe system and state III for cracked pipes with larger deformations and considerable risk to collapse in the near future. State II sewers but installed close to the traffic surface must be calculated as a state III situation too. According to the code stress, deformation and stability tests are necessary. For many practical cases charts with stress factors and imperfection reductions allow to design without a computer. Numerous theoretical and experimental papers are available which mainly deal with circular linings. An evaluation of design codes carried out by experts of different countries shows a fairly good coincidence of the required wall thicknesses, but the assessment of pipeline damages by engineers is sometimes resulting in quite different assumptions necessary for the design input parameters. The paper reports about the progress in liner design since the 1st edition of the code. Additional clauses have to be introduced into the 2nd edition for non circular geometries (e.g. for hood and rectangular profile), imperfections describing practical and theoretical situations and new applications (e.g. railway crossings). International discussion can be useful to find safe and resources saving constructions.