I am working on an old and progressively added to STW with three separate process streams. Flow splitting is achieved by hydraulic balance but because distribution channels are of different lengths and shapes the associated head losses also differ. Ideally I require equal flow division between the three streams but because of the differing head losses, flow to the three streams can vary by up to +/- 20%.
I am charged with providing a more equal flow division. The preferred method is via modulating penstocks (there is not the head or space for a weir based system) to counter the different losses through the distribution channels. However the required head loss is typically between 20mm and 40mm and no more than 100mm. Using the formulas for a vertical sluice gate it appears that the penstocks need to operate in the lower quarter to generate sufficient velocity through the opening but the results are dependant on discharge coefficient used (assumed for our purposes 0.3) but for this application, is outside the normal parameters of these formulas. Consequently the results have to be viewed with some suspicion. Does any one have any a experience of such obtaining such small relative losses via this method, are there other formulas I can use or other cost effective methods.
Key data
The distribution channels I am interested in have a width of 1.2m with a depth that varies between 2.3 and 2.6m. The flow in each channel will nominally vary between 500l/s and 1900l/s. The penstock is only intended to modulate 2-3 times per hour.
I am charged with providing a more equal flow division. The preferred method is via modulating penstocks (there is not the head or space for a weir based system) to counter the different losses through the distribution channels. However the required head loss is typically between 20mm and 40mm and no more than 100mm. Using the formulas for a vertical sluice gate it appears that the penstocks need to operate in the lower quarter to generate sufficient velocity through the opening but the results are dependant on discharge coefficient used (assumed for our purposes 0.3) but for this application, is outside the normal parameters of these formulas. Consequently the results have to be viewed with some suspicion. Does any one have any a experience of such obtaining such small relative losses via this method, are there other formulas I can use or other cost effective methods.
Key data
The distribution channels I am interested in have a width of 1.2m with a depth that varies between 2.3 and 2.6m. The flow in each channel will nominally vary between 500l/s and 1900l/s. The penstock is only intended to modulate 2-3 times per hour.
