What is Rayleigh and Fanno line?
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What is Rayleigh and Fanno line?
Fanno and Rayleigh line, when plotted on h-s plane, for same mass velocity G, intersect at 1 and 2.as shown in fig. All states of Fanno line have same stagnation temperature or stagnation enthalpy, and all states of Rayleigh line have same stream thrust F / A.
What is isothermal flow give two examples?
11.7. 6: Isothermal Flow Examples
| Isothermal Flow | Input: P2/P1 and 4fLD | |
|---|---|---|
| M1 | M2 | 4fLD|max |
| 0.7272 | 0.84095 | 0.05005 |
| 0.6934 | 0.83997 | 0.08978 |
| 0.6684 | 0.84018 | 0.12949 |
What is fanno line expansion?
Concept: Fanno Flow: Flow in a constant area duct with friction and without heat transfer is known as Fanno Flow. As initial flow is supersonic. If we reduce the pipe length then due to this, friction will be decreased.
What is non isothermal flow?
Being nonisothermal flow refers to fluid flows with temperatures that are not constant. When a fluid is subjected to a temperature change, its material properties, such as density and viscosity, change accordingly.
What is meant by isothermal flow?
Isothermal flow is a model of compressible fluid flow whereby the flow remains at the same temperature while flowing in a conduit. In the model, heat transferred through the walls of the conduit is offset by frictional heating back into the flow.
What is critical length in Fanno flow?
Case 1: Fanno Flow: M is the inlet Mach number. The critical length of the pipe is the length required for the flow to choke at the exit (i.e. M = 1 at exit). With an inlet Mach no of 0.5 and a friction factor of 0.002, and pipe diameter of 6 inches the critical length is calculated to be 3207 inches.
What is a Fanno line in physics?
The line representing the locus of points with the same mass velocity and stagnation enthalpy is called a Fanno line. It is a one-dimensional model for adiabatic flow in a constant area duct with friction. It is a combination of continuity and energy equations.
What is bleed flow and Rayleigh flow?
The bleed flow will be studied under two cases: one involving frictional effects i.e. Fanno Flow and the other involving heat addition i.e. Rayleigh Flow. These two. cause for change of state is termed Rayleigh flow. Applied Gas Dynamics, John with no external work, is called Fanno line flow.
What is the use of Fanno flow in ductwork?
Fanno flow is used to analyze flow of fluid through a duct where heat transfer is negligible and friction must be considered. In a duct of constant cross section, entropy increases in the direction of flow as a consequence of irreversibility due to friction.
Why does the Fanno flow have a choked state?
Because the flow is viscous, energy is dissipated through the channel, generating heat. Just like the Rayleigh flow, because the Fanno flow is heated by viscous effects rather than by an external heater, the flow tends towards a choked state no matter if it’s subsonic or supersonic.