Is flow work different from displacement work?
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Is flow work different from displacement work?
Flow work is necessary for maintaining a continuous flow through a control volume. A control volume may involve one or more forms of work at the same time. Work-Energy transfer in thermodynamics under quasi static process is known as work displacement.
What is flow work?
DEFINITION: Flow work is the energy necessary to cause flow in an open system. The simplest way to account for this is to use enthalpy in open systems rather than energy since H = U + PV, in order to account for both internal energy and flow work at the same time.
What is a displacement work?
=pdV. where dV – change in volume. This work is known as displacement work or pdV work corresponding to the elemental displacement dx. To obtain the total work done in a process, this elemental work must be added from the initial state to the final state.
What is flow work in thermodynamics?
Work is needed to push the fluid into or out of the boundaries of a control volume if mass flow is involved. This work is called the flow work (flow energy). The work done due to pushing the fluid element out of the control volume is the same as the work needed to push the fluid element into the control volume.
What is an example of flow?
The definition of a flow is an act of moving or running smoothly, a movement of water or the continuous moving of ideas, stories, etc. An example of a flow is a steady movement through the development of a research paper. An example of a flow is the movement of a stream.
What is the formula for flow work?
The work done in pushing the fluid is: Wflow = F.s = PA. s = PV (kJ) or in a unit basis, wflow = Wflow / m = Pv (kJ/kg) Note that the flow work is expressed in terms of properties. The flow work can also be written as a rate equation.
What is the difference between flow and non flow process?
Differentiate between non-flow and flow process. Flow process: It is one in which fluid enters the system and leaves it after work interaction, which means that such processes occur in the systems having open boundary permitting mass interaction across the system boundary.
Why is flow work PV?
The volume is not compressed or expanded, but it is displaced. The work done is pressure (assumed constant) times volume displaced. The flow work done on a unit mass that is displaced into the control volume is Pv.