Explain the following terms. i) Spcific speed (ii) Run away speed (iii) Degree of reaction

i) Specific speed: Specific speed is a term used in fluid dynamics to describe the characteristic speed of a pump or turbine. It is defined as the speed at which a geometrically similar impeller would operate if it were of unit size and were delivering or absorbing unit power. Specific speed is typically denoted by the symbol Ns and is calculated using the formula Ns = (N * √Q) / H^(3/4), where N is the rotational speed of the impeller, Q is the flow rate, and H is the head.

ii) Runaway speed: Runaway speed refers to the maximum speed at which a rotating machine, such as a turbine or motor, can operate without experiencing any mechanical failure or damage. It is the speed beyond which the machine's components, such as bearings or shafts, may become unstable or fail due to excessive centrifugal forces or other factors. Runaway speed is an important parameter to consider in the design and operation of rotating machinery to ensure safe and reliable operation.

iii) Degree of reaction: Degree of reaction is a term used in the analysis of axial flow turbines and compressors. It is a measure of the proportion of the total pressure drop that occurs in the rotor section of the machine. In other words, it quantifies the extent to which the rotor blades convert the kinetic energy of the fluid into mechanical work. The degree of reaction is typically expressed as a percentage and is calculated by dividing the pressure drop in the rotor by the total pressure drop across the machine. A higher degree of reaction indicates a greater conversion of kinetic energy into mechanical work by the rotor blades.