
This value of slope has the same order of magnitude
as the experimental value.
3.7 Calculations in large rivers.
One strategy may be to adjust a sufficient mass of
tracer, M, and place two fluorimetry measurement
devices, E1 and E2, in sequence, so that several state
function data can be obtained. With equation (8) and
the adjustment of the experimental data, an
extrapolation can be made to the required distance,
D, in the section of the channel under study. within
reasonable limits, which allow the tracer
concentration curve to be modeled, and from there
the corresponding calculations can be derived, as
explained in this article. The variances of the data at
the extrapolation point will be minimized if it is
considered that in principle, the river is in “Dynamic
equilibrium”. Figure 15.
Figure 15.- Extrapolation of measurements by means
of State function.
In the case being studied, applying the approximate
model for Φ(tp), from equation (8), the comparison
is made with the experimental data as shown below.
As you can see, the data is of the same order.
Table 4:
Table 4.- Comparison between Φ(tp) calculated with equation
(8), and the experimental data in Table 3.
Φ (t) model,
equation (8)
4. Conclusions
1.- The key to revealing the values of the hydraulics
in a natural cause is to have a state function such as
Φ(t) that allows calculating the various parameters
involved, both dispersive and advective, and also
making an approximate connection with the
geomorphological parameters.
2.- With this theoretical tool it is possible to
extrapolate calculations to greater distances to which
tracer tests are carried out, which in this way will
require less mass of tracer and facilitate the
experimental part.
3.- A criterion is developed to know when a natural
flow has assimilated (diluted) the mass of
contaminant, based on the calculation of the
percentage of the cross-sectional area covered by the
tracer.
4.-The method presented based on a new equation of
the average velocity, allows connecting and
calculating the most important parameters of river
mechanics, ensuring precise and statistically
homogeneous values to successfully feed the models.
5.- The method is applied to examine in detail an
experiment documented by the USGS in 1963, with
satisfactory results. These results suggest that the
presented method can be applied to solve the
obtaining of critical data for the modeling of large or
medium-sized channels.
References
[1] Fischer H.B. The mechanics of dispersion in
natural streams. Journal of Hydraulics Division.
November, (1967).
[2] Godfrey R.& Frederick B. Dispersion in natural
streams. USGS Open file. (1963).
[3]Fischer H.B. Dispersion predictions in natural
streams. Journal of Sanitary Eng. October, (1968).
[4] Constain A. Verificación del transporte de
trazador radiactivo usando un Coeficiente función del
tiempo en cauces naturales. Dyna, No.175. Medellín,
(2012).
[5] Constaín A., Lemos R. & Carvajal A. Tecnología
IMHE: Nuevos desarrollos de la hidráulica. Revista
Ingeniería Civil, CEDEX, Madrid. No. 129. (2003).
[6] Constain A. Definición y análisis de una función
de evolución de solutos dispersivos en flujos
naturales. Dyna, No. 175. Medellín, (2012).
[7] Stewart I. ¿Juega Dios a los dados? Grijalbo-
Mondadori. Barcelona. (1991).
[8] Karapetiants M. & Drakin S. Estructura de la
sustancia. Editorial Mir, Moscú.(1974).
EARTH SCIENCES AND HUMAN CONSTRUCTIONS
DOI: 10.37394/232024.2024.4.11
Alfredo Jose Constain Aragon