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## COMPUTATION MENU |

In this menu you can find the commands that help establish the basin's balance, its high flood flows for every section, homogeneous and permanent flow conditions verification and the riverbed section view (longitudinal profile).

Hydro graphical and Morphometrical Analysis

For every basin defined by a break point an analysis is performed regarding its morphometrical proprieties and its time of concentration. During this phase the program carries out also the computations for every sub-basin automatically generated according to the position of each breakpoint.

After the analysis is completed alterations can be undertaken for every sub-basin from the control panel in the right of the work area. Activating the <Basin vertices alteration> command every sub-basin can be shaped according to the project reqiures. After doing this the calculation must be redone.

Triangularization

This operation is carried out automatically by the program for the morphometrical and hydro graphical analysis. This command enables the basin's 3D view and its printing from the preview window - to activate it press the right button of the mouse.

Carries out the computations using Kennessey's flow coefficient. For this parameter, compulsory for the next step in the hydrological balance, the following data must be provided:

rainfall: expressed in mm of rain, for expressing P rushes;

medium temperature: monthly medium temperature;

maximum temperature: monthly maximum temperature;

minimum temperature: monthly minimum temperature.

The program calculates the aridity index for provided data, from which, depending on the calculation for the surface slices that define the vegetal distribution, the steepness and the permeability, the partial and total efflux coefficient are obtained.

In this window are asked the main basin's inflow and outflow data.

In this window are computed long rain data (1 – 3 – 6 – 12 – 24 hours for several years); consequently the basin's Rain model is defined. The program performs the calculation of the rain's maximum and critical height corresponding to every day and period (1, 3, 6, 12, 24 hours), in function of every recurrence interval assigned by the user in General Data from the Data Input menu.

Rain data acquired from a rainfall station can be directly filled in the period's table or copied from another file.

The program computes data with Gumbel's probability distribution, and finds the parameters, the medium standard deviation, k and m.

The Rainfall Probability Curve graphic is available in semi-algorithmic and algorithmic scale (x and y). By pressing the right button of the mouse you can copy the graph to clipboard, paste it in bitmap image format or copy the containing values for another project.

The print report allows sending input data and results to the printer.

High flood flow - Empirical Methods

For every transversal section the high flood flow is calculated with empirical methods. This requires the author's selection. The program reads the flow value in m³/sec, the specific flow in m³/sec Km².

High flood flow - Empirical and Rational Method

For the assigned Recurrence interval the program calculates the high flood flow corresponding with the specified transversal section. The program develops a flow analysis for every sub-basin on the activation of the <Flows analysis> command. The calculation differs on the selection of the method to use Rational, Analytical or TCEV IN General Data.

For every recurrence interval assigned by the user the program generates the high flood hygrograph with Nash's method. In the respective window, for every elected transversal section can be viewed: k and n function parameters, basin's characteristics (calculated with Nash or Mc Sparran) and n and a Rain model parameters (for every Tr). Calculation step, in hours, and the maximum period (hours) are user defined; in order to change them press the <Recalculate> button. The graphic can be copied to clipboard and can then be pasted in bitmap image format by holding down the mouse and choosing the <Copy Graphic> command. For exporting the curve's values you can choose the <Copy Format> from the same menu.

Uniform flow hydraulic verification

For every selected section the program carries out the uniform flow conditions verification. The verification sections definition (transversal sections) takes place before this stage, so, after having developed the Hygrograph and Morphological Analysis, the program proceeds with the determination of the maximum high flood flow (empirical and classical methods). Every sections' roughness and form must be defined. Sections' generation can be obtained by activating the <Transversal section> command from the Data Input menu (or the toolbar) and clicking on the section line previously determined.

Permanent flow conditions

In this window the user can assign the analysis conditions for the permanent flow for every recurrence interval. Regarding the downhill conditions the liquid section's height is defined within the transversal section; regarding the uphill conditions the liquid section's height is determined within the uphill liquid source section.

These conditions, once defined the scanning step between the sections, are use in computing the total weight and the free elevation in the successive sections.

Knowing the initial section's geometry and flow (downhill and uphill conditions) - that we indicate as i section, the program calculates the J fall and the total load, so, once the scanning step has been determined the same dimensions (fall and load) are being calculated for different h values (around the h defined).

In the next step, the program calculates the load loss between the initial section and the successive one (i+1 ) and obtains, for the interpolarisation of the values found for different h heights, the section's liquid height (i+1). For the first height obtained hi+1, the program develops the computation of J fall and obtains the medium value of the fall (the average of the fall in i and that of the fall in i+1 ), from which follows the computation of the total load loss. A t this point the program finds the hi+1 height by interpolating the previously found values with the constant scanning step.

Permanent fall hydraulical verification

For every transversal section it is being calculated the liquid section's height for a determined verification flow, as shown previously. The computation can be done for the several overflow periods' flows. In order for the computation to converge the verification flow for every section is extremely important. Once the computation has been performed the program has determined for every section the h height, establishing for every fragment if its dealing with a low or high inclination riverbed and consequently if the current is slow or fast.

Overfill mapping

The command shows the high flood area for every recurrence interval. The overfill mapping is available only after the sections' verification in permanent flow conditions. For printing it choose the <Print Preview> command.

Riverbed section preview

Views the longitudinal section of the riverbed with the water profile height determined in slice by slice flow conditions. For returning to the basin's view deselect the command.

Data block/free

command that allows to block or free the input/ output data.