Breakage resistance of a Polycarbonate plate with flowed through drill hole

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Ekaekto
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Hi everyone,

I was wondering how to best calculate the breakage resistance of a drill hole which is being flowed through with a certain volumetric throughput within a polycarbonate (PC) rectangular plate. Well basically, the breakage resistance of the PC around the drill hole :)

The plate is 150X40X12 mm in LXWXH and the smallest distance of a drill hole to the edge of the plate is 8.8mm. The drill hole is 4mm in length and 1.6mm in diameter (there is a larger drill hole, which I needn't calculate at the 8mm of the rest of the height of the plate ;) )

The volumetric throughput is at 35 ml/min = 5.833333333345e-7 m^3/s, it's water at 20°C, so the dynamic viscosity is 1e-3 kg/ms
The speed of the water through the drill hole was modeled with the use of Solidworks FloXpress to equal 0.5 m/s.
I just want to know whether the PC plate will withstand the volumetric throughput without breaking.

The idea of a friend was to approach this problem as if the drill hole and surround plate was a thick-walled hollow cylinder under only interior pressure with inner diameter=1.6mm and outer diameter=2*8.8+1.6 mm = 19.2mm.
However when he calculated it, he calculated a factor of safety around 7.5e5, which seems exorbitantly high.

Thanks for your help. :)
 
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A sectional diagram of the hole would better communicate the situation.
What is the maximum pressure drop through the hole, across the PC plate ?
Is cavitation possible at step changes in diameter ?