At the top left hand side of Figure 07.05.06 a conical cylinder turbine T is shown. The pipes running up the inside of the cone are set with a 16 cm radius at the lower edge of the cone (R16) and a 24 cm radius (R24) at the top of the cone. These pipes therefore have a curved shape as they run up the inside face of the cone. These pipes can be thought of as performing the same function as turbine blades in a jet engine.
In the same way as before, a jet of water is fed at an upward angle of 30 degrees into the bottom of the pipes. Unlike the previous case, the jet of water does not strike the walls of the pipes at their lowest point because the water is entering parallel to a diagonal wall. In this case, as before, the overall height of the cylinder is 24 cm. The track taken by the water will be exactly the same as the previous track, running from A to B shown in the previous diagram, and again spanning a sector of 150 degrees (S150).
The central diagram of Figure 07.05.06 shows the conical cylinder surface laid out flat. The dark blue curve C shows the path taken by the jet of water as it spirals upwards and outwards from A to B, within the sector S150 shaded in blue. Interestingly, since the cone circumference at the outlet level is longer than at the inlet level (having 24 cm and 16 cm lengths respectively), The cone actually rotates at a greater speed than the speed of the water. This means that the water accelerates as it passes up through the curved pipes inside the cone (although that is not the intended job of any turbine).
As shown in the top right hand diagram, the pipes inside this conical turbine need to be curved backwards in the opposite direction to that in which the turbine rotates. These pipes are curved to follow the path shown in red and marked G which is contained within the 50 degree sector S50.
As stated earlier, the water flowing in these pipes presses against the outer wall, due to centrifugal force. Once the water speed is great enough, the water gets lifted upwards by its own motion. If the pipes allow that additional upward motion, then the water will exit from the top of the pipes at a more acute angle than the angle of entry at the bottom of the pipes.
The bottom diagram shows a design arrangement where the water enters at an angle of 30 degrees (point E), and exits at the same 30 degree angle (at point F). With this arrangement, the water travels along a shorter, steeper path D in a narrower sector of just 120 degrees (S120). Due to this shorter path, the pipe follows a different curve, such as the one shown in red and marked H in the diagram. The pipe itself, is contained in a sector of just 40 degrees (S40).
The diagram at the top right hand side of the Figure, show this short pipe run. The water enters at point A and flows upwards through the pipe marked G, to exit at point B. Notice that the pipe curves away from the direction of rotation. This is because the pipe acts something like a jet engine and the direction of thrust is in the opposite direction to the direction of the jet of water coming out of the pipe. The pipe shown in this illustration covers a sector of 50 degrees. However, remember that the water flowing in that pipe covers a sector of 150 degrees due to the rotation of the turbine cone. The lower pipe H shows the other design and it spans just 40 degrees. Water in that pipe flows upwards from E to F and passes through 120 degrees due to the rotation of the turbine cone, and it also flows faster and reaches its outlet earlier. These different pipes are only shown on a single turbine cone for illustration purposes, as any turbine construction will have all of its pipes constructed to one design or the other and not a mix of the two shapes.
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