| 2. |
- Moilanen, C., et al.
(författare)
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Modelling and simulation of radial spruce compression to optimize energy efficiency in mechanical pulping
- 2016
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Ingår i: International Mechanical Pulping Conference 2016, IMPC 2016. - : TAPPI Press. - 9781510830738 ; , s. 18-35
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Konferensbidrag (refereegranskat)abstract
- Energy efficiency of mechanical pulping is rather low. One possibility to facilitate design of more energy efficient defibration is to model and simulate wood compression. This paper presents an effort to model the behavior of Norwegian spruce in radial compression at defibration circumstances. To identify strain rate dependent properties, compression tests were conducted at both quasi-static conditions and at high strain rate. All tests were done at relevant moisture content and up to defibration zone temperatures and strain rates. Additionally the tests were performed both on native wood and on pre-fatigued wood to include behavior dependency of fatigue. The compression tests were monitored on fiber level to separately model behavior of early- and latewood. The chosen continuum model structure for earlywood and latewood was Voight-Kelvin to enable explicit viscous behavior conditioned by strain rate in parallel to the elastic behavior. The presented model is the first wood compression behavior model individually for earlywood and latewood that is based on wood experiments at industrial defibration circumstances. The influences of temperature and pre-fatigue rise are both softening as expected, The utilization of the compression model was demonstrated in an initial multilayered wood compression simulation.
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| 4. |
- Petäjä, Tuukka, et al.
(författare)
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Overview : Integrative and Comprehensive Understanding on Polar Environments (iCUPE) - concept and initial results
- 2020
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Ingår i: Atmospheric Chemistry And Physics. - : Copernicus GmbH. - 1680-7316 .- 1680-7324. ; 20:14, s. 8551-8592
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Tidskriftsartikel (refereegranskat)abstract
- The role of polar regions is increasing in terms of megatrends such as globalization, new transport routes, demography, and the use of natural resources with consequent effects on regional and transported pollutant concentrations. We set up the ERA-PLANET Strand 4 project iCUPE - integrative and Comprehensive Understanding on Polar Environments to provide novel insights and observational data on global grand challenges with an Arctic focus. We utilize an integrated approach combining in situ observations, satellite remote sensing Earth observations (EOs), and multi-scale modeling to synthesize data from comprehensive long-term measurements, intensive campaigns, and satellites to deliver data products, metrics, and indicators to stakeholders concerning the environmental status, availability, and extraction of natural resources in the polar areas. The iCUPE work consists of thematic state-of-the-art research and the provision of novel data in atmospheric pollution, local sources and transboundary transport, the characterization of arctic surfaces and their changes, an assessment of the concentrations and impacts of heavy metals and persistent organic pollutants and their cycling, the quantification of emissions from natural resource extraction, and the validation and optimization of satellite Earth observation (EO) data streams. In this paper we introduce the iCUPE project and summarize initial results arising out of the integration of comprehensive in situ observations, satellite remote sensing, and multi-scale modeling in the Arctic context.
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