(4. 1.35b. Hydrodynamic flow through a porous diaphragm Consider the hydrodynamic flow of nitrogen at 400K through the porous diaphragm described in Example 1.24. It is desired to achieve a superficial gas velocity through the diaphragm of 0.28kg of N2/m2s by increasing the upstream pressure while maintaining the downstream pressure constant at 0.1atm. Calculate the upstream pressure required. Answer: 13.64kPa