| ATTRIBUTE | VALUE |
|---|
| type | A |
| database id | 8549 |
| title | Modelling of flood wave propagation with wet-dry front by one-dimensional diffusive wave equation |
| authors | Gąsiorowski D. |
| pages | 111 — 125 |
| full text link | http://www.ibwpan.gda.pl/storage/app/media/ahem/ahem61str111.pdf |
| keywords | diffusive wave equation, shallow water equations, overland flow, floodplain inundation, finite element method |
| affiliations | - Gdańsk University of Technology, Faculty of Civil and Environmental Engineering, ul. G. Narutowicza 11/12, 80-233 Gdańsk, Poland, e-mail: dariusz.gasiorowski@wilis.pg.gda.pl
|
| abstracts | A full dynamic model in the form of the shallow water equations (SWE) is often useful for
reproducing the unsteady flow in open channels, as well as over a floodplain. However, most
of the numerical algorithms applied to the solution of the SWE fail when flood wave propagation
over an initially dry area is simulated. The main problems are related to the very small
or negative values of water depths occurring in the vicinity of a moving wet-dry front, which
lead to instability in numerical solutions. To overcome these difficulties, a simplified model
in the form of a non-linear diffusive wave equation (DWE) can be used. The diffusive wave
approach requires numerical algorithms that are much simpler, and consequently, the computational
process is more effective than in the case of the SWE. In this paper, the numerical
solution of the one-dimensional DWE based on the modified finite element method is verified
in terms of accuracy. The resulting solutions of the DWE are compared with the corresponding
benchmark solution of the one-dimensional SWE obtained by means of the finite volume
methods. The results of numerical experiments show that the algorithm applied is capable of
reproducing the reference solution with satisfactory accuracy even for a rapidly varied wave
over a dry bottom. |
| attributes | [reviewed] [scientific] |
| language | en |
| ATTRIBUTE | VALUE |
|---|
| type | A |
| database id | 8550 |
| title | Velocity field characteristics at the inlet to a pipe culvert |
| authors | Kolerski T., Wielgat P. |
| pages | 127 — 140 |
| full text link | http://www.ibwpan.gda.pl/storage/app/media/ahem/ahem61str127.pdf |
| keywords | culvert, Acoustic Doppler Velocitymeter, velocity field, turbulence |
| affiliations | - Gdańsk University of Technology, Faculty of Civil and Environmental Engineering, ul. G. Narutowicza 11/12, 80-233 Gdańsk, Poland, e-mail: tomasz.kolerski@wilis.pg.gda.pl
|
| abstracts | A poorly designed culvert inlet structure causes scouring, which can lead to the collapse of the
culvert and significant damage to the neighboring land. A set of laboratory tests was evaluated
to examine velocity distribution at the culvert inlet. A three-dimensional acoustic Doppler
velocimeter was used to measure instantaneous flow velocity upstream of the culvert. The analysis
of mean velocities, turbulence strength, and Reynolds stresses was performed to understand the
flow structure near the culvert entrance. |
| attributes | [reviewed] [scientific] |
| language | en |
| ATTRIBUTE | VALUE |
|---|
| type | A |
| database id | 8551 |
| title | Impact of urbanization on stormwater runoff from a small urban catchment: Gdańsk Małomiejska basin case study |
| authors | Olechnowicz B., Weinerowska-Bords K. |
| pages | 141 — 162 |
| full text link | http://www.ibwpan.gda.pl/storage/app/media/ahem/ahem61str141.pdf |
| keywords | urban development, basin runoff, numerical modeling, green roofs, permeable pavement |
| affiliations | - Gdańsk University of Technology, Faculty of Civil and Environmental Engineering, Department of Hydraulic Engineering, ul. G. Narutowicza 11/12, 80-233 Gdańsk, Poland, e-mail: kwein@pg.gda.pl
|
| abstracts | This paper deals with the impact of different forms of urbanization on the basin outflow. The
influence of changes in land cover/use, drainage system development, reservoirs, and alternative
ways of stormwater management (green roofs, permeable pavements) on basin runoff was
presented in the case of a small urban basin in Gdańsk (Poland). Seven variants of area development
(in the period of 2000-2012) - three historical and four hypothetical - were analyzed.
In each case, runoff calculations for three rainfall scenarios were carried out by means of the
Hydrologic Modeling System designed by Hydrologic Engineering Center of the U.S. Army
Corps of Engineers (HEC-HMS). The Soil Conservation Service (SCS) Curve Number (CN)
method was used for calculations of effective rainfall, the kinematic wave model for those of
overland flow, and the Muskingum-Cunge model for those of channel routing. The calculations
indicated that urban development had resulted in increased peak discharge and runoff volume
and in decreased peak time. On the other hand, a significant reduction in peak values was
observed for a relatively small decrease in the normal storage level (NSL) in reservoirs or when
green roofs on commercial centers were present. The study confirmed a significant increase
in runoff as a result of urbanization and a considerable runoff reduction by simple alternative
ways of stormwater management. |
| attributes | [reviewed] [scientific] |
| language | en |
| ATTRIBUTE | VALUE |
|---|
| type | A |
| database id | 8552 |
| title | Application of the boundary element method for the simulation of two-dimensional viscous incompressible flow |
| authors | Prybytak D. |
| pages | 163 — 173 |
| full text link | http://www.ibwpan.gda.pl/storage/app/media/ahem/ahem61str163.pdf |
| keywords | mathematical modeling, numerical solution, boundary element method, flow of a Stokes liquid |
| affiliations | - Gdańsk University of Technology, Faculty of Civil and Environmental Engineering, ul. G. Narutowicza 11/12, 80-233 Gdańsk, Poland, e-mail: dzmpryby@student.pg.gda.pl
|
| abstracts | The paper presents the application of an indirect variant of the boundary element method
(BEM) to solve the two-dimensional steady flow of a Stokes liquid. In the BEM, a system
of differential equations is transformed into integral equations. This makes it possible to limit
discretization to the border of the solution. Numerical discretization of the computational
domain was performed with linear boundary elements, for which a constant value of unknown
functions was assumed. The verification was carried out for the case of flow in a square cavity
with one moving wall. The results obtained show that the use of approximations by simple
linear functions is relatively easy for different shapes of the area, but the result may be affected
by significant errors. |
| attributes | [reviewed] [scientific] |
| language | en |
| ATTRIBUTE | VALUE |
|---|
| type | A |
| database id | 8553 |
| title | Experimental determination of limit adhesive shear stress between solid wall and liquid |
| authors | Sawicki J. |
| pages | 175 — 181 |
| full text link | http://www.ibwpan.gda.pl/storage/app/media/ahem/ahem61str175.pdf |
| keywords | hydromechanics, slip boundary condition, adhesion |
| affiliations | - Gdańsk University of Technology, Faculty of Civil and Environmental Engineering, ul. G. Narutowicza 11/12, 80-233 Gdańsk, Poland, e-mail: jsaw@pg.gda.pl
|
| abstracts | The slip boundary condition can be a very useful relation when some specific problems of
hydromechanics are considered. According to the classical form of this condition, the slip of a
fluid with respect to the solid wall should occur even at a very low velocity of motion. However,
both theoretical analysis and certain empirical data suggest that there must be a limit value of
the wall shear stress, below which the slip does not occur. According to the simplified balance
of adhesive and gravitational forces, a simple experimental method for determining this stress
has been proposed and applied in this paper. |
| attributes | [reviewed] [scientific] |
| language | en |
| ATTRIBUTE | VALUE |
|---|
| type | A |
| database id | 8555 |
| title | Outlet flow velocity in circular culvert |
| authors | Szpakowski W. |
| pages | 193 — 203 |
| full text link | http://www.ibwpan.gda.pl/storage/app/media/ahem/ahem61str193.pdf |
| keywords | culvert conveyance, outlet velocity, circular culvert, critical flow |
| affiliations | - Gdańsk University of Technology, Faculty of Civil and Environmental Engineering, ul. G. Narutowicza 11/12, 80-233 Gdańsk, Poland, e-mail: wojciech.szpakowski@wilis.pg.gda.pl
|
| abstracts | The outlet flow velocity in the end section of the culvert barrel depends in most cases on the
culvert geometry, including the barrel slope, as well as on upstream and downstream channel
parameters. Flowing water can create pressure flow or free surface flow in the culvert barrel.
In the case of an unsubmerged barrel outlet, the free-surface flow is more frequent than the
full flow. Increased velocities can cause channel bed scour and bank erosion downstream of
the culvert outlet. Different culvert flow cases in which the barrel outlet is unsubmerged are
presented in this paper. The influence of the flow regime on the outlet velocity is also discussed. |
| attributes | [reviewed] [scientific] |
| language | en |
| ATTRIBUTE | VALUE |
|---|
| type | A |
| database id | 8557 |
| title | Numerical simulations and tracer studies as a tool to support water circulation modeling in breeding reservoirs |
| authors | Zima P. |
| pages | 217 — 229 |
| full text link | http://www.ibwpan.gda.pl/storage/app/media/ahem/ahem61str217.pdf |
| keywords | breeding reservoir hydraulics, water circulation, tracer study, mathematical modeling, kinematical models |
| affiliations | - Gdańsk University of Technology, Faculty of Civil and Environmental Engineering, ul. G. Narutowicza 11/12, 80-233 Gdańsk, Poland, e-mail: pzima@pg.gda.pl
|
| abstracts | The article presents a proposal of a method for computer-aided design and analysis of breeding
reservoirs in zoos and aquariums. The method applied involves the use of computer simulations
of water circulation in breeding pools. A mathematical model of a pool was developed,
and a tracer study was carried out. A simplified model of two-dimensional flow in the form
of a biharmonic equation for the stream function (converted into components of the velocity
vector) was adopted to describe the flow field. This equation, supplemented by appropriate
boundary conditions, was solved numerically by the finite difference method. Next, a tracer
migration equation was solved, which was a two-dimensional advection-dispersion equation
describing the unsteady transport of a non-active, permanent solute. In order to obtain a proper
solution, a tracer study (with rhodamine WT as a tracer) was conducted in situ. The results of
these measurements were compared with numerical solutions obtained. The results of numerical
simulations made it possible to reconstruct water circulation in the breading pool and to
identify still water zones, where water circulation was impeded. |
| attributes | [reviewed] [scientific] |
| language | en |
| ATTRIBUTE | VALUE |
|---|
| type | A |
| database id | 8548 |
| title | Comparison of average energy slope estimation formulas for one-dimensional steady gradually varied flow |
| authors | Artichowicz W., Mikos-Studnicka P. |
| pages | 89 — 109 |
| full text link | http://www.ibwpan.gda.pl/storage/app/media/ahem/ahem61str089.pdf |
| keywords | open channel, steady flow, gradually varied flow, standard step method, energy slope |
| affiliations | - Gdańsk University of Technology, Faculty of Civil and Environmental Engineering, ul. G. Narutowicza 11/12, 80-233 Gdańsk, Poland, e-mail: wojciech.artichowicz@wilis.pg.gda.pl
|
| abstracts | To find the steady flow water surface profile, it is possible to use Bernoulli’s equation, which is
a discrete form of the differential energy equation. Such an approach requires the average
energy slope between cross-sections to be estimated. In the literature, many methods are proposed
for estimating the average energy slope in this case, such as the arithmetic mean, resulting in the
standard step method, the harmonic mean and the geometric mean. Also hydraulic averaging
by means of conveyance is commonly used. In this study, water surface profiles numerically
computed using different formulas for expressing the average slope were compared with exact
analytical solutions of the differential energy equation. Maximum relative and mean square
errors between numerical and analytical solutions were used as measures of the quality of
numerical models. Experiments showed that all methods gave solutions useful for practical
engineering purposes. For every method, the numerical solution was very close to the analytical
one. However, from the numerical viewpoint, the differences between the methods were
significant, as the errors differed up to two orders of magnitude. |
| attributes | [reviewed] [scientific] |
| language | en |