Figure 07.05.09 attempts to give the impression of the spiral arrangement of the previously described tooth-shaped notches running around the surface of the turbine cone. The cone-like mountain shape has faces A running all around it. These faces start at a low angle and then become steeper as they rise higher. Each of these has a vertical wall B alongside it, formed by the side of the next innermost face. These faces are not visible at the right hand side of the diagram as their downward slopes are hidden from view.
For clarity, in this diagram the cone is shown inverted, and so the direction of rotation appears clockwise, but in reality, when in its correct position, the rotation will be counter-clockwise. Notice in the upper diagram, that the incoming water D hits these faces at nearly a right-angle, providing substantial thrust in the direction of the arrows.
As the lower diagram shows the top view of the inverted cone it has the appearance of a conical hill. At points E and F, lines are marked which indicate the height of the saw tooth shaped indentations in the surface of the cone. The lines at E represent the pressure-side, while at F the inner side indicates only the slope surface and thus no 'suction-side' exists.
Now these indentations are not arranged to run straight down but are shifted as shown in the diagram at point G. Previous vertical indentations E now create the pressure-wall H, which corresponds to the previous indentation A in its spiral path. The inner-walls F of the earlier indentations thus create the surface M through their vertical walls B. In effect, the whole hill is built from these successive 'winding staircases', which admittedly actually don't have any stairs. These paths spiral upwards with progressively smaller radius and increasing steepness.
At point N in the diagram, part of several of these spiral pathways is shown. Here, the vertical walls between them are visible only as small blue curves. The whole of the surface area of this
turbine cone is a pressure-side because of these spiral surfaces running all around it. Like diagonally falling rain, water flows all around the surfaces of that hill in its downward flow, and anywhere it is forced to turn right it generates a rotational force on the turbine cone. Remember that this machine has a cone-shaped housing which ensures that the water flows exactly in its intended path.
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