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What is constant in throttling?

What is constant in throttling?

Throttling is a process where a high-pressure fluid is converted into low-pressure by using a throttle valve. In a throttling process, the enthalpy remains constant and the work done is zero.

Which process is constant after throttling?

Explanation: If steam is throttled, its enthalpy remains constant and pressure drop takes place.

How can you explain the steady flow condition?

Steady-state flow is defined as a flow condition under which the pressure at any point in the reservoir remains constant over time. This flow condition prevails when the pressure funnel shown in Fig. 3.1 has propagated to a constant-pressure boundary.

What is throttling phenomenon?

When the fluid flows through the pipe with the throttling device, the phenomenon that the static pressure of the fluid is different at the pipe bores before and after the throttling device is called the throttling phenomenon.

Is throttling always Isenthalpic?

A throttling process is a thermodynamic process, in which the enthalpy of the gas or medium remains constant (h = const). In fact, the throttling process is one of isenthalpic processes.

Why Does entropy increase in throttling?

Because of the viscous heat generation in the throttling operation, the temperature change is small, and so the decrease in pressure (increase in volume) will result in an increase in entropy.

Is free expansion reversible?

The free expansion of a gas is an irreversible process; in principle, the temperature of a gas undergoing a free expansion is not a meaningful quantity.

What is an example of steady flow?

Steady flow of fluid is a condition where the function of fluid property is time independent. For example consider fluid flow in a tapered pipe, which may be steady, but the velocity and acceleration need not be constant. Some examples of steady flow devices include pipes, nozzles, diffusers, and pumps.

What does a steady flow mean?

A steady flow is one in which all conditions at any point in a stream remain constant with respect to time. The exact term use for this is mean steady flow. Steady flow may be uniform or non-uniform. Uniform flow. A truly uniform flow is one in which the velocity is same at a given instant at every point in the fluid.

What happens in a throttling valve?

With the throttling valve control method, the pump runs continuously, and a valve in the pump discharge line is opened or closed to adjust the flow to the required value. To understand how the throttling controls flow rate, see Figure 4.11. With the valve fully open, the pump operates at Flow 2.

How throttling process is isenthalpic?

A throttling process is a thermodynamic process, in which the enthalpy of the gas or medium remains constant (h = const). During the throttling process no work is done by or on the system (dW = 0), and usually there is no heat tranfer (adiabatic) from or into the system (dQ = 0).

What is the purpose of throttling process?

Throttling process is a thermodynamic process which is used to reduce or decrease the pressure of a fluid. In this process a liquid having high pressure is converted into low pressure fluid.

Is the throttling process an irreversible steady flow expansion?

The throttling process is an irreversible steady flow expansion process in which a perfectgas is expanded through an orifice of minute dimensions such as a narrow throat or aslightly opened valve.

What are the characteristics of a throttling process?

Characteristics of throttling process: A throttling of the flow causes significant reduction in pressure, becauses a throttling device causes a local pressure loss. A throttling can be achieved simply by introducing a restriction into a line through which a gas or liquid flows.

How are throttling valves used in steady flow engineering devices?

If a pump tried to pump a gas it could be damaged. The same goes for a compressor, if it were used to compress a liquid it would most likely ruin the compressor. A throttling valve is a steady flow engineering device that is used to restrict flow. A considerable pressure drop will result from the restricted flow.

When does throttling process cause no change in enthalpy?

If the changes in kinetic and potential energy are negligible, this flow process is called as throttling process, which causes no change in enthalpy between the inlet and the outlet: Δ H = 0. Some properties of throttling processes are: In an ideal gas, enthalpy is a function of temperature only, and temperature remains constant.