Numerical modelling of physical processes in a ballistic laboratory setup with a tapered adapter and plastic piston used for obtaining high muzzle velocities

In consequence of sea ice fragmentation in winter a range of physical processes take place between the sea/sea ice and the atmospheric boundary layer (ABL). Most of them occur on the level of individual ice floes and cracks and thus cannot be directly resolved by numerical weather prediction (NWP) models.&#160; Parametrizations of those processes aim to describe their overall effect on grid scale values, given the grid scale variables. However, as many of the processes taking place during winter sea ice fragmentation remain largely unrecognized they cannot be incorporated into the NWP models.&#160;The aim of the presented study is to determine whether the floe size distribution (FSD) has an effect on the ABL. Our previous research (Wenta, Herman 2018 and 2019) indicates that FSD might determine the intensity and spatial arrangement of convection and heat fluxes. A coefficient has been proposed for the correction of moisture heat flux, which can be incorporated into the NWP models. However, this research is based entirely on idealized model simulations and requires further modelling and observations based studies.In order to address this shortcoming, a field campaign is going to take place in the Bay of Bothnia in March 2020. Our goal is to create a 3D view of the atmosphere above fragmented sea and verify whether the processes and effects we found in the modeling results take similar form in real situations. Measurements results will be useful in the validation of our numerical modelling studies and will provide a unique dataset about the sea-ice-atmosphere interactions in the Bay of Bothnia area. Considering a significant decreasing trend in winter sea ice extent in the Baltic Sea it might contribute to our understanding of the role of ice in the local weather patterns. The field campaign is going to be complemented by numerical modelling with full version of Weather Research and Forecasting (WRF) model adjusted to the conditions over the Bay of Bothnia.&#160;Combined together - the results of our previous modelling studies and the results from the Bay of Bothnia field campaign, may considerably increase our knowledge about the surface-atmosphere coupling in the event of winter sea ice fragmentation.

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Numerical modelling of heavy rainfall event over Madeira Island in Portugal: sensitivity to different micro physical processes

Meteorological Applications ◽

10.1002/met.1375 ◽

2013 ◽

Vol 22 (1) ◽

pp. 113-127 ◽

Cited By ~ 21

Author(s):

Hari Prasad Dasari ◽

Rui Salgado

Keyword(s):

Numerical Modelling ◽

Heavy Rainfall ◽

Rainfall Event ◽

Heavy Rainfall Event ◽

Physical Processes ◽

Madeira Island

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European Semi-enclosed Seas: Basic Physical Processes and Their Numerical Modelling

Preventive Methods for Coastal Protection ◽

10.1007/978-3-319-00440-2_5 ◽

2013 ◽

pp. 131-179 ◽

Cited By ~ 1

Author(s):

Emil V. Stanev ◽

Xi Lu

Keyword(s):

Numerical Modelling ◽

Physical Processes

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Shocks in Molecular Clouds

Publications of the Astronomical Society of Australia ◽

10.1017/s1323358000020944 ◽

1996 ◽

Vol 13 (3) ◽

pp. 268-271

Author(s):

Peter W. J. L. Brand

Keyword(s):

Numerical Modelling ◽

Statistical Models ◽

Molecular Clouds ◽

Gas Flow ◽

Molecular Gas ◽

Physical Processes ◽

Star Forming ◽

Nonlinear Growth ◽

Star Forming Regions ◽

Shock Dynamics

AbstractA one-day workshop discussed the properties of shocks in star-forming regions. It also reviewed other physical processes in star-forming molecular gas, and the progress in numerical modelling of such physics. Discussion concentrated on the complexity which instabilities in the gas flow bring to the analysis of shocks. The consensus was that progress will be made as the spatial/spectral resolution of shock measurements improves, and as numerical modelling of the nonlinear growth of instabilities becomes possible, potentially leading to statistical models of shock dynamics.

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Recent advances in coronal heating

Philosophical Transactions of The Royal Society A Mathematical Physical and Engineering Sciences ◽

10.1098/rsta.2014.0269 ◽

2015 ◽

Vol 373 (2042) ◽

pp. 20140269 ◽

Cited By ~ 59

Author(s):

Ineke De Moortel ◽

Philippa Browning

Keyword(s):

Numerical Modelling ◽

Heat Source ◽

Thermal Conduction ◽

Solar Surface ◽

Coronal Heating ◽

Future Research ◽

Small Scale ◽

The Sun ◽

Physical Processes ◽

Outer Atmosphere

The solar corona, the tenuous outer atmosphere of the Sun, is orders of magnitude hotter than the solar surface. This ‘coronal heating problem’ requires the identification of a heat source to balance losses due to thermal conduction, radiation and (in some locations) convection. The review papers in this Theo Murphy meeting issue present an overview of recent observational findings, large- and small-scale numerical modelling of physical processes occurring in the solar atmosphere and other aspects which may affect our understanding of the proposed heating mechanisms. At the same time, they also set out the directions and challenges which must be tackled by future research. In this brief introduction, we summarize some of the issues and themes which reoccur throughout this issue.

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Experimental and Numerical Modelling of Self-Potential Response to Saltwater Intrusion

10.5194/egusphere-egu21-8861 ◽

2021 ◽

Author(s):

Eric Benner ◽

Gerard Hamill ◽

Georgios Etsias ◽

Thomas Rowan ◽

Pablo Salinas ◽

...

Keyword(s):

Finite Element ◽

Numerical Modelling ◽

Coastal Aquifers ◽

Saltwater Intrusion ◽

Geophysical Methods ◽

Excess Charge ◽

Adaptive Meshing ◽

Finite Element Software ◽

Laboratory Setup ◽

Self Potential

Saltwater intrusion (SWI) in coastal aquifers poses a significant hazard to freshwater security for many of the world&#8217;s population centers. SWI is challenging to monitor and model due to the physical complexity of real aquifers. Self-Potential (SP) has been an important method for monitoring the subsurface for many years. Previous studies have suggested that borehole measurements of SP could be used to identify saline interface movement and provide advance warning of imminent saline breakthrough at an abstraction borehole. SP produced during SWI comprises the combined effects of electro-kinetic potential, arising from transport of excess charge in response to water potential (head) gradients, and exclusion-diffusion potential, arising from transport of excess charge in response to ion (salt) concentration gradients. SP can have advantages over other geophysical methods, such as electrical resistivity tomography and borehole fluid electrical conductivity measurements, because the effect of &#160;moving saltwater fronts can be determined using a relatively small number of localized probes.We quantitatively investigate the relationship between SP and SWI using experimental and numerical modelling with the aim of reproducing experimentally measured SP response via simulation. Building on well-established methods, a novel laboratory setup has been developed to optically monitor SWI in a thin homogenous aquifer while simultaneously recording SP data at multiple probe points. A Matlab solver is used to calculate SP data from simulated hydrodynamic SWI data computed by the fixed-grid finite element software SUTRA. Similarly, finite element SWI simulations using adaptive meshing are carried out using the IC-FERST software, which directly computes hydrodynamic and SP solutions. We compare these numerical results with experimental data and show similarity in SP signal trends as functions of brine movement near probe locations. We conclude with a discussion of the merits of SP modelling and its suitability for interpreting SP signals for monitoring and characterization of saltwater intrusion in coastal aquifers.

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