Navigation mit Access Keys

Contenuto principale

 

Benjamin Walter

 

Funzione

collaboratore scientifico

  

Istituto Neve e Valanghe
Flüelastrasse 11
7260 Davos Dorf

Sito

Davos Da B 1 19

 

 

 

Research interests

Snow sciences:

- Snow and it's interaction with the atmosphere

- Drifting and blowing snow

- Snow microstructure

Fluid dynamics:

- Aeolian research (wind erosion, particle entrainment, shear stress partitioning, Owens hypothesis)

- Porous media flow (water flow through snow)

Instrumentation:

 

- Measuring snow properties, turbulent flow,  particle mass fluxes, fluid shear stress, solar radiation etc. to improve our understanding of complex environmental processes

- Improve and develop new instrumentation

 

 

Education

Aug 2002 – Jun 2008

Academic studies: Physics, Karlsruhe Institute of Technology (KIT), Germany

Aug 2005 – Jul 2006

Exchange studies: Physics, Kungliga Tekniska Högskolan (KTH) Stockholm, Sweden

Jun 2007 – Jun 2008

Master thesis: Fraunhofer Institute for Solar Energy Systems (ISE), Freiburg, Germany. Title of thesis: Quantitative analysis of spatially resolved lock-in-thermography measurements for the characterization of silicon solar cells

Nov 2008 – May 2012

Doctoral studies: WSL Institute for Snow and Avalanche Research SLF, Davos, Switzerland. Title of thesis: Wind tunnel studies of shear stress partitioning in live plant canopies; Degree: “Doctor of science”

 

Employments

Jul 2008 – Oct 2008

Scientific assistant: Fraunhofer ISE, Freiburg, Germany

May 2012 – Jul 2012

Guest Researcher: WSL Institute for Snow and Avalanche Research SLF, Davos, Switzerland

Aug 2012 – Jun 2013

 

Post-Doc: WSL Institute for Snow and Avalanche Research SLF, Davos, Switzerland, Group: Snow Cover and Micrometeorology

July 2013 – Sep 2018

 

Post-Doc / Research associate: Physikalisch-Meteorologisches Observatorium Davos / World Radiation Center (PMOD / WRC), Davos, Switzerland

Oct 2018 – now

Research associate: WSL Institute for Snow and Avalanche Research SLF, Davos, Switzerland, Group: Snow Processes

 

Publications

Remesal O, Finsterle W, Walter B, Schmutz W (2018) Characterisation of a new carbon nanotube detector coating for solar absolute radiometers, Journal of Physics: Conference Series, Volume 972, doi.org/10.1088/1742-6596/972/1/012007

Walter B, Levesque P-L, Kopp G, Andersen B, Beck I, Finsterle W, Gyo M, Heuerman K, Koller S, Mingard N, Remesal Oliva A, Pfiffner D, Soder R, Spescha M, Suter M, Schmutz W (2017) The CLARA/NORSAT-1 absolute radiometer: instrument design, characterization and calibration, Metrologia 54 (2017) 674–682

Walter B, Winkler R, Graber F, Finsterle W, Fox V, Li V, Schmutz W (2017) Direct Solar Irradiance measurements with a Cryogenic Solar Absolute Radiometer, AIP Conference Proceedings 1810, 080007, doi.org/10.1063/1.4975538

Walter B, Voegeli C, Horender S (2017) Estimating sediment mass fluxes on surfaces sheltered by live vegetation, Boundary-Layer Meteorol (2017) 163: 273. doi.org/10.1007/s10546-016-0224-z

Ball W, Schmutz W, Fehlmann A, Finsterle W, Walter B (2016) Assessing the beginning to end-of-mission sensitivity change of the PREcision MOnitor Sensor total solar irradiance radiometer 3 (PREMOS/PICARD) J. Space Weather Space Clim. 6 A32, doi.org/10.1051/swsc/2016026

Walter B, Fehlmann A, Finsterle W, Suter M, Soder R, Schmutz W (2014) Spectrally integrated window transmittance measurements for a cryogenic solar absolute radiometer, Metrologia, Vol. 51, 344–349, iopscience.iop.org/article/10.1088/0026-1394/51/6/S344

Walter B, Horender S, Voegeli C, Lehning M (2014) Experimental assessment of Owen’s second hypothesis on surface shear stress induced by a fluid during sediment saltation, Geophysical Research Letters, Vol. 41, doi.org/10.1002/2014GL061069

Gromke C, Horender S, Walter B, Lehning M (2014) Snow particle characteristics in the saltation layer, Journal of Glaciology, Vol. 60, No. 221, doi.org/10.3189/2014JoG13J079

Walter B, Horender S, Gromke C, Lehning M (2013) Measurements of the pore-scale water flow through snow using Fluorescent Particle Tracking Velocimetry, Water Resources Research, Vol. 49, 7448–7456, doi.org/10.1002/2013WR013960

Walter B, Gromke C, Leonard K, Manes C, Lehning M (2012c) Shear stress partitioning in live plant canopies and modifications to Raupach’s model. Boundary-Layer Meteorology, link.springer.com/article/10.1007%2Fs10546-012-9719-4

Walter B, Gromke C, Leonard K, Manes C, Lehning M (2012b) Spatio-temporal surface shear-stress variability in live plant canopies and cube arrays. Boundary-Layer Meteorology, link.springer.com/article/10.1007%2Fs10546-011-9690-5

Walter B, Gromke C, Leonard K, Clifton A, Lehning M (2012a) Spatially resolved skin friction velocity measurements using Irwin sensors: A calibration and accuracy analysis. Journal of Wind Engineering and Industrial Aerodynamics, doi.org/10.1016/j.jweia.2012.02.018

Gromke C, Manes C, Walter B, Lehning M, Guala M (2011) Aerodynamic roughness length of fresh snow. Boundary-Layer Meteorology, doi.org/10.1007/s10546-011-9623-3 

Kasemann M, Walter B, Warta W (2009) Reliable hot-spot classification in 10 ms using ultrafast lock-in thermography, Progress in photovoltaics: Research and applications, 17:441–450

Kasemann M, Grote D, Walter B, Kwapil W, Trupke T, Augarten Y, Bardos R A, Pink E, Abbott M D, Warta W (2008) Luminescence imaging for the detection of shunts on silicon solar cells, Progress in Photovoltaics: Research and Applications,16:4, 297-305

Kasemann M, Walter B, Meinhardt C, Ebser J, Kwapil W, Warta W (2008) Emissivity-corrected power loss calibration for lock-in thermography measurements on silicon solar cells, Journal of Applied Physics, 103:11, 113503-113503-8