Question about turbines logic In thermodynamics, according to some book exercises, a fluid can enter a turbine and come out with greater speed compared to the inlet speed. It makes sense looking at the conservation of energy equations, if the fluid enters with high internal and flow energy (high enthalpy). 
Thing is, isn't it required actual KINECTIC energy for the turbine blades to move? So how possible is a fluid leaving faster than when it entered in a TURBINE? That would make sense in a hidraulic pump.
 A: Energy conservation is still valid if you look at the equation $$dE=\delta Q +\delta W$$ In turbine, we can ignore potential energy, thus $$dU + dE_k=\delta Q +\delta W$$ You can then see, reduction in internal energy can be used to generate heat, output heat and increase kinetic energy. It can many thing as long as it abides the second Law. 
A: There's plenty of fluid colliding with the blades inside of a turbine.  Turbines are of two types:  'reaction' and 'impulse'.  Inside the same machine, there may be parts which operate on the reaction principle and parts which operate on the impulse principle.
Turbines are often designed with alternating rows of fixed and moving blades.  The fixed blades direct the working fluid so that the moving blades turn.
For impulse blades, the working fluid is designed to impinge on the blades directly, causing them to move.
In a reaction turbine, changes to the pressure or mass flow of the working fluid causes a reaction on the moving blades.  High-pressure in the working fluid is converted to an equivalent velocity head, which is described by Bernoulli's theorem.
A: The turbine operates with a constant mass flow rate.  If the gas pressure decreases through the turbine, and the decrease in temperature is not sufficient to offset this (which it typically won't be), the specific volume of the gas will increase.  This will mean that the volumetric flow rate at the outlet will be higher than at the inlet.  If the cross sectional areas of the inlet and the outlet are the same, the gas velocity at the outlet will be higher than at the inlet.
