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Main Question or Discussion Point
ρ
I am trying to estimate and validate the pressure of water exiting a nozzle. For an unknown reason, the validation is consistently twice as high as the estimation.
Here the approach:
Estimation:
I am using the dynamic pressure equation for the estimation:
q = 1/2 * ρ * u^{2}
where,
q = dynamic pressure
ρ = density of water (997 kg/m^{3})
u = liquid velocity
The velocity is calculated based on the known nozzle diameter and the flow rate (u = flow rate / nozzle area)
Validation:
The measurement is performed by simply measuring the jet force with a force gauge in horizontal orientation and in short distance (<1cm)  see the schematic. The assumption is that the jet diameter is the same as the nozzle.
q_val = jet force / nozzle area.
As mentioned before, in varying measurements the validation is close to being twice of the estimation data.
Is there anything I'm missing here?
I am trying to estimate and validate the pressure of water exiting a nozzle. For an unknown reason, the validation is consistently twice as high as the estimation.
Here the approach:
Estimation:
I am using the dynamic pressure equation for the estimation:
q = 1/2 * ρ * u^{2}
where,
q = dynamic pressure
ρ = density of water (997 kg/m^{3})
u = liquid velocity
The velocity is calculated based on the known nozzle diameter and the flow rate (u = flow rate / nozzle area)
Validation:
The measurement is performed by simply measuring the jet force with a force gauge in horizontal orientation and in short distance (<1cm)  see the schematic. The assumption is that the jet diameter is the same as the nozzle.
q_val = jet force / nozzle area.
As mentioned before, in varying measurements the validation is close to being twice of the estimation data.
Is there anything I'm missing here?
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