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-   -   I want to predict the performance of the axial flow fan. (

Sanghyun - PARK April 14, 2013 22:33

I want to predict the performance of the axial flow fan.
I speak English a little.

Fan Specifications condition

Volume Flow rate : 36.8[m^3/s]
Total Pressure : 539[Pa] = 55[mmAq]
Static Prssure : 0[pa] = 0[mmAq]
Used motor : 50Hp = 37kw
RPM : 1760 rpm

1. What conditions are optimized conditions?
ex) Inlet : no.1 Outlet : No.4

2. I want to see the Total Pressure & Static Pressure efficiency.
ex) A. Pt[pa] =Outlet Lid Pt(SG av) - Inlet Lid Pt(SG av)

B. Ps[Pa]= Outlet Lid Ps(SG av) - Inlet Lid Pt(SG av)
↑↑↑↑ What is the exact official this?

C. Volume Flow[m^3/s] = Inlet Lid (SG av) Volume Flow

D. W = Impeller Torque * Rotating region

E. (C * A or B) / ( D ) = Efficiency?

It is really important to me.?

Thank you.
Thank you.

Boris_M April 30, 2013 04:31

Hi Sanghyun,

It is not 100% clear to me what your problem is but I will try to help you.

1. The ideal boundary conditions for fan simulations are inlet volume/mass flow and outlet pressure. There is an example in the tutorials on an impeller. This model is a radial fan but the basic setup is the same. You can find it on page C5-1.

2. You can also find the right formula for this calculation in the tutorial (page C5-5)

Efficiency = (volume flow rate [m^3/s] * (Ps_outlet [Pa] - Ps_inlet [Pa]))/(torque [Nm] * rotating speed [rad/s])

I hope this helps,

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