| ATTRIBUTE | VALUE |
|---|
| type | A |
| database id | 8948 |
| title | Determination of mechanical energy loss in steady flow by means of dissipation power |
| authors | Wojciech Artichowicz, Jerzy M. Sawicki |
| pages | 73 — 85 |
| DOI | 10.1515/heem-2017-0005 |
| full text link | http://www.ibwpan.gda.pl/storage/app/media/ahem/ahem64str073.pdf |
| keywords | energy decay rate, energy loss |
| affiliations | - Gdańsk University of Technology, Faculty of Civil and Environmental Engineering, ul. G. Narutowicza 11/12, 80-233 Gdańsk, Poland, e-mails: wojartic@pg.edu.pl, jsaw@pg.edu.pl
|
| abstracts | When systems of simple geometry like pipes or regular channels are considered, the mechanical energy loss of the fluid flow can be expressed by local and longitudinal empirical energy loss coefficients. However, in the case of large spatially distributed objects, there are no simple approaches to this task. In practice, general recommendations addressing different types of objects are used, but they usually provide very coarse estimates of energy loss. In this work, a new methodology for determination of mechanical energy loss in steady flow is proposed.
This methodology is based on the observation that the magnitude of the power of energy dissipation in turbulent flow can be determined using the averaged flow velocity and turbulent viscosity coefficient. To highlight this possibility, an analysis of the magnitudes of the power of the main and fluctuating components of turbulent flow is presented.
The correctness of the method is verified using an example of laminar and turbulent flows in a circular pipe. The results obtained show clearly that the proposed methodology can be used for mechanical energy loss determination in flow objects. This methodology can be used as a basis for mechanical energy loss determination in different types of flow objects. |
| attributes | [reviewed] [scientific] |
| language | en |
| ATTRIBUTE | VALUE |
|---|
| type | A |
| database id | 8893 |
| title | Influence of the geometry alteration of the landslide slope on its stability: A case study in the Carnian Alps (Italy) |
| authors | Zabuski L., Bossi G., Marcato G. |
| pages | 101 — 114 |
| DOI | 10.1515/heem-2017-0007 |
| notes | Kopia w opracowaniu Tp4494 |
| full text link | http://www.ibwpan.gda.pl/storage/app/media/ahem/ahem64str101.pdf |
| keywords | geotechnical modelling, landslide risk, monitoring, numerical calculation |
| affiliations | - Institute of Hydro-Engineering, Polish Academy of Sciences, Kościerska 7, 80-328 Gdańsk, Poland, Corresponding author, e-mail: lechu@ibwpan.gda.pl
- CNR-IRPI – National Research Council, Institute for Geo-Hydrological Protection, Italy e-mails: giulia.bossi@irpi.cnr.it; gianluca.marcato@irpi.cnr.it
|
| abstracts | The paper presents the principles of the slope reprofiling and proves the effectiveness of this stabilization measure. The case study of two adjacent landslides in the National Road 52 “Carnica” in the Tagliamento River valley, the Carnian Alps (46 ◦ 23 0 49 00 N, 12 ◦ 42 0 51 00 E) are the example allowing for illustration of this approach. The phenomena have been studied for more than a decade, making it possible to carry out a detailed geological and geomorphological reconstruction. That was done on the basis of a large amount of monitoring data collected during that period. Since the landslides are threatening an important road, countermeasure works to ameliorate the stability conditions of the slides need to be designed. The paper focuses on the creation of a numerical model consistent with monitoring data and capable of reconstructing the dynamics of both landslides. Two cross-sections, one for each landslide, were selected for the analysis. The geometry of the slip surface was determined on the basis of control points, such as slip surface readings from inclinometers, and geomorphological evidence for the contour. The FLAC2D code was used to evaluate the current stability of these landslides and to determine the effectiveness of changing the slope geometry by removing material from the upper part of the slope and putting it to the lowest part as reinforcement. |
| attributes | [reviewed] [scientific] |
| language | en |
| ATTRIBUTE | VALUE |
|---|
| type | A |
| database id | 8892 |
| title | Modeling of waves propagating in water with a crushed ice layer on the free surface |
| authors | Szmidt K. |
| pages | 87 — 99 |
| DOI | 10.1515/heem-2017-0006 |
| full text link | http://www.ibwpan.gda.pl/storage/app/media/ahem/ahem64str087.pdf |
| keywords | gravitational wave, crushed ice, wave damping |
| affiliations | - Institute of Hydro-Engineering, Polish Academy of Sciences, Kościerska 7, 80-328 Gdańsk, Poland, e-mail: jks@ibwpan.gda.pl
|
| abstracts | A transformation of gravitational waves in fluid of constant depth with a crushed ice layer floating on the free fluid surface is considered. The propagating waves undergo a slight damping along their path of propagation. The main goal of the study is to construct an approximate descriptive model of this phenomenon. With regard to small displacements of the free surface, a viscous type model of damping is considered, which corresponds to a continuous distribution of dash-pots at the free surface of the fluid. A constant parameter of the dampers is assumed in advance as known parameter of damping. This parameter may be obtained by means of
experiments in a laboratory flume. |
| attributes | [reviewed] [scientific] |
| language | en |
| ATTRIBUTE | VALUE |
|---|
| type | A |
| database id | 8894 |
| title | SPH Modelling of Sea-ice Pack Dynamics |
| authors | Staroszczyk R. |
| pages | 115 — 137 |
| DOI | 10.1515/heem-2017-0008 |
| notes | kopia w opracowaniu Tp4482 |
| full text link | http://www.ibwpan.gda.pl/storage/app/media/ahem/ahem64str115.pdf |
| keywords | sea-ice dynamics, Lagrangian description, smoothed particle hydrodynamics, moving boundary problem |
| affiliations | - Institute of Hydro-Engineering, Polish Academy of Sciences, Kościerska 7, 80-328 Gdańsk, Poland
|
| abstracts | The paper is concerned with the problem of sea-ice pack motion and deformation under the action of wind and water currents. Differential equations describing the dynamics of ice, with its very distinct material responses in converging and diverging flows, express the mass and linear momentum balances on the horizontal plane (the free surface of the ocean). These equations are solved by the fully Lagrangian method of smoothed particle hydrodynamics (SPH). Assuming that the ice behaviour can be approximated by a non-linearly viscous rheology, the proposed SPH model has been used to simulate the evolution of a sea-ice pack driven by wind drag stresses. The results of numerical simulations illustrate the evolution of an ice pack, including variations in ice thickness and ice area fraction in space and time. The effects
of different initial ice pack configurations and of different conditions assumed at the coast–ice interface are examined. In particular, the SPH model is applied to a pack flow driven by a vortex wind to demonstrate how well the Lagrangian formulation can capture large deformations and displacements of sea ice. |
| attributes | [reviewed] [scientific] |
| language | en |