turbomachinery Turbomachinery, in mechanical engineering, describes machines that transfer energy between a Rotor (electric), rotor and a fluid, including both turbines and gas compressor, compressors. While a turbine transfers energy from a fluid to a rotor, ...

, a velocity triangle or a velocity diagram is a triangle representing the various

components Component may refer to: In engineering, science, and technology Generic systems *System components, an entity with discrete structure, such as an assembly or software module, within a system considered at a particular level of analysis * Lumped e ...

of velocities of the

working fluid For fluid power, a working fluid is a gas or liquid that primarily transfers force, motion, or mechanical energy. In hydraulics, water or hydraulic fluid transfers force between hydraulic components such as hydraulic pumps, hydraulic cylinders, a ...

in a turbomachine. Velocity triangles may be drawn for both the inlet and outlet sections of any turbomachine. The

vector Vector most often refers to: * Euclidean vector, a quantity with a magnitude and a direction * Disease vector, an agent that carries and transmits an infectious pathogen into another living organism Vector may also refer to: Mathematics a ...

nature of velocity is utilized in the triangles, and the most basic form of a velocity triangle consists of the tangential velocity, the absolute velocity and the relative velocity of the fluid making up three sides of the triangle.

Components

A general velocity triangle consists of the following vectors: : =

absolute velocity Velocity is a measurement of speed in a certain direction of motion. It is a fundamental concept in kinematics, the branch of classical mechanics that describes the motion of physical objects. Velocity is a vector quantity, meaning that both m ...

of the fluid. : = blade linear velocity. : =

relative velocity The relative velocity of an object ''B'' relative to an observer ''A'', denoted \mathbf v_ (also \mathbf v_ or \mathbf v_), is the velocity vector of ''B'' measured in the rest frame of ''A''. The relative speed v_ = \, \mathbf v_\, is the v ...

of the fluid after contact with

rotor ROTOR was an elaborate air defence radar system built by the British Government in the early 1950s to counter possible attack by Soviet bombers. To get it operational as quickly as possible, it was initially made up primarily of WWII-era syst ...

. : = tangential component of (absolute velocity), called ''Whirl velocity''. : = flow velocity (axial component in case of axial machines, radial component in case of radial machines). The following angles are encountered during the analysis: : = absolute angle is an angle made by with the plane of the machine (usually the nozzle angle or the guide blade angle) i.e. angle made by absolute velocity and the direction of blade rotation . : = relative angle is an angle made by relative velocity and direction of blade rotation.

References

{{Reflist Mechanical engineering Fluid mechanics