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If throttling reduces mass flow rate then how can we say it as steady flow process where the mass flow rate is constant?
boneh3ad said:Yes but for a set valve position, mass flow doesn't change between the upstream and downstream side of the valve, yet it has still reduced the maximum flow rate that the system can attain. If you change the valve position while it is running there will be a brief transient period but then it settles into a steady state with lower mass flow.
What kind of pump is it?Signature said:If my pump's rated capacity is 100 Cu.m/hr and i adjusted the valve position to get only 50 Cu.m/hr. How the pump's capacity will reduce according to the valve position?
Just for example I quoted, CentrifugalChestermiller said:What kind of pump is it?
I couldn't get your point. How mass would accumulate in valve?CWatters said:If the mass flow rate was higher before the valve than if was after the valve then mass would accumulate in the valve!
(Rate of Flow in) - (Rate of Flow out) = (Rate of Accumulation). According to what you have been saying, this has to be what is happening in the valve.Signature said:I couldn't get your point. How mass would accumulate in valve?
Chestermiller said:(Rate of Flow in) - (Rate of Flow out) = (Rate of Accumulation). According to what you have been saying, this has to be what is happening in the valve.
But in steady flow process Mass flow rate in and out should be equal. So there won't be any mass accumulation in valve, but may be in pipeline upstream of the valveChestermiller said:(Rate of Flow in) - (Rate of Flow out) = (Rate of Accumulation). According to what you have been saying, this has to be what is happening in the valve.
Signature said:If my pump's rated capacity is 100 Cu.m/hr and i adjusted the valve position to get only 50 Cu.m/hr. How the pump's capacity will reduce according to the valve position?
Signature said:I couldn't get your point. How mass would accumulate in valve?
Signature said:So in a pipeline if there is a flow rate of 50 Cu.m/hr upstream of the valve and 40 Cu.m/hr flow rate downstream of the valve (incompressible fluid), then the fluid entering the valve is only 40 Cu.m/hr. Is that right?
Thanks a lot...CWatters said:This is the equivalent of an irresistible force applied to an immovable object. They both cannot "win".
Either
a) The valve wins, restricting the flow to 50. eg by causing an increase in back pressure that slows down the pump.
or
b) The pump wins and delivers 100. The valve is unable to restrict the flow.
or
c) Something in between a and b. For example the valve partially manages to slow the pump and you get somewhere between 50 and 100.
Throttling is a process in which the flow rate of a fluid is controlled by restricting its cross-sectional area. This results in a decrease in the fluid's velocity and an increase in its pressure.
Throttling causes a decrease in the velocity of the fluid, which leads to an increase in its pressure. This is due to the conservation of mass and energy principles, where the decrease in velocity results in an increase in pressure.
Yes, throttling is considered a steady flow process because the flow rate remains constant throughout the process. This means that the fluid properties, such as velocity and pressure, do not change with time.
The main factor that affects throttling is the size of the restriction or valve used to control the flow rate. Other factors that may affect throttling include the properties of the fluid, such as density and viscosity, and the initial pressure and temperature of the fluid.
Throttling is commonly used in various engineering and scientific applications, such as in engines to control the flow of fuel, in refrigeration systems to regulate the flow of refrigerant, and in industrial processes to control the flow of fluids. It is also used in hydraulic systems, turbines, and many other devices that require precise control of fluid flow.