To measure flow rate, the float method (also known as the cross-sectional method) is used. It is found by
multiplying a cross sectional area of the stream by the velocity of the water.
To measure the flow rate using the float method:
1. Locate a spot in the stream that will act as the cross section of the stream.
2. Using a meter stick, or some other means of measurement, measure the depth of the stream at
equal intervals along the width of the stream. Once this data is gathered, multiply each depth by the
interval it was taken in and add all the amounts together. This calculation is the area of a cross
section of the stream.
3. Decide on a length of the stream, typically longer than the width of the river, to send a floating object
down.
4. Using a stopwatch, measure the time it takes the float to travel down the length of stream.
5. Repeat it 5-10 times and determine the average time taken for the float to travel the stream. Throw
the float into the water at different distances from the shoreline in order to gain a more accurate
average.
6. Divide the stream length by the average time to determine the average velocity of the stream.
7. Alternatively use a water flow velocity meter to measure the speed.
8. The velocity must be multiplied by a friction correction factor. Since the top of a stream flows faster
than the bottom due to friction against the stream bed, the friction correction factor evens out the
flow. For rough or rocky bottoms, multiply the velocity by 0.85. For smooth, muddy, sandy, or
smooth bedrock conditions, multiply the velocity by a correction factor of 0.9.
9. The corrected velocity multiplied by the cross sectional area yields the flow rate in volume/time.
(Be sure to keep consistent units of length/distance when measuring the cross section and the
velocity e.g. meters, feet).
To measure the water flow velocity perform steps 3-7.
https://www.appropedia.org/How_to_measure_stream_flow_rate
What are considered to be the maximum feasible distances for transmission wire run?
This depends on the scale of the system, the power available, cost of alternatives, the system voltage, and
the terrain, among other factors.
There are too many variables involved to generalize on distance limits. Financial feasibility is usually the
governing factor. How much is the power worth? Note that transmitting small amounts of energy, such as
an energy-efficient household would use, can be pretty inexpensive over long distances.
Every site is unique, and careful balancing of factors is required. Ultimately, the maximum feasible
distance is directly related to the depth of your checkbook and what is “worth it” to you.
Bigger diameter wires allow for longer distances but they also cost more.
What are the advantages of the SETUR system compared to other renewable electricity systems
(wind turbine, PV array)?
SETUR system will generate continuously, if it has a constant water supply. This alone is a significant
advantage over either wind or solar power because a battery bank may not be required, and a smaller
battery bank will suffice if one is needed.
Vortex Hydrokinetics LLC © 2019
SETUR-M User's Manual - Rev. 2M-A
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