From the Bernaulli Equation we know that when the velocity increases the pressure must decrease. So why in case of a pump the pressure increases with outlet velocity being more ? Also please explain to me how the pressure for a turbine is less at the outlet. Thank You.
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Bernoulli equation in the form you have mentioned is applicable to flows in which no work is being done on/by the flow. If there is work transfer, which is the case for flow created by a pump beginning from reservoir to outlet, we have the modified Bernoulli equation (neglecting change in height): $p_1+\frac{1}{2}\rho v_1^2+\textrm{Work done}=p_2+\frac{1}{2}\rho v_2^2$. In this case increase in outlet speed $v_2$ can be accompanied by increase in outlet pressure $p_2$ because "work done" term is positive.
