Power house arrangements and hydraulic

Fig. 5 The arrangement of the Kaplan turbine in Solbergfoss power plant 

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Fig. 6 Kongsvinger power plant with a Kaplan Bulb turbine 
 
Hydraulic forces transferred to power house.  
This chapter gives a brief summary of the hydraulic forces transferred through the turbine 
to the power house foundations.
The main forces from a turbine installed in a power house are transferred through the spiral 
casing for Francis and Kaplan turbines with steel spiral casing. For vertical Pelton turbines 
the forces are transferred through the manifold to the concrete. 
The horizontal hydraulic force, which is the dominating force of a Kaplan Bulb turbine, is 
transferred to the concrete via the outer cone and the main struts which transfer the axial 
hydraulic forces from the turbine. The torque from the generator stator is transferred through 
the generator support. The axial hydraulic force on the runner is transferred through the 
thrust bearing via the bulb through the stress carrying structure to the concrete.
Going back to the high head turbines and starting with the vertical Pelton turbines we can 
summarise the following dimensioning forces from the turbine to the powerhouse: 
The hydraulic forces from the horizontal turbines like SKJAAK (fig 8) are normally 
transferred to the penstock inlet flange via a ridged connection through a spherical inlet 
valve. Thus only minor reaction forces from the jets and momentum forces from the 
deflectors during rejection are transferred to the turbine housing. The jet forces on the runner 
will be transferred to the radial bearing of the generator, which is bolted to the concrete 
foundation. These forces are transferred to the surrounding concrete. 

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