QS Energy Inc (QSEP)

[Myrka]

Suppose you have a pipe with a length of 3 miles. The liquid of viscosity V has a flow rate of F thanks to the pump at the beginning of the pipe.
You miraculously change the viscosity of the 1 mile in the middle from V to 0.
You then have a system equivalent to 2 miles at viscosity V, right ?
The pump is the same. So the flow should be higher than F, no ???

In previous posts Alkaline and I agreed that lowering the viscosity is like having a larger pipe size. So I am going to use that premise and exaggerate sizes to make my point more visual. As you say, lets imagine viscosity of nearly 0 in the middle segment of your 3 mile pipe. In other words, a larger pipe, to properly visualize this setup, lets go further and make it a reservoir one mile long followed by the last segment of a one mile pipe. Apply to the system a flow rate F, the results would be: filling of the reservoir first between the two length of pipes. Once full, resumption of the flow rate F down the last mile of pipe. This is where you need to read about conservation of mass in a closed system. That reservoir or the larger segment of pipe will not speed up the flow, in fact it will take more time for a quantity of oil to reach the end of the 3 mile pipe even though it is at the same flow rate. That's because it has to continually fill that reservoir before reaching the end of the pipe. Now, you are going to argue that increasing the pipe size and lowering the viscosity are not the same. You would be right, but it does illustrate the law of conservation of mass. Hence, a constant flow rate whether you stick a larger pipe size or a length of pipe with fluid at a lower viscosity in the middle of a closed system.

Wikipedia:
The law of conservation of mass, or principle of mass conservation, states that for any system closed to all transfers of matter and energy (both of which have mass), the mass of the system must remain constant over time, as system mass cannot change quantity if it is not added or removed. Hence, the quantity of mass is "conserved" over time. The law implies that mass can neither be created nor destroyed, although it may be rearranged in space, or the entities associated with it may be changed in form, as for example when light or physical work is transformed into particles that contribute the same mass to the system as the light or work had contributed. The law implies (requires) that during any chemical reaction, nuclear reaction, or radioactive decay in an isolated system, the total mass of the reactants or starting materials must be equal to the mass of the products.

The concept of mass conservation is widely used in many fields such as chemistry, mechanics, and fluid dynamics.