Hi PF! Can someone help me understand how to draw lines of constant pressure in an inviscid flow field, say flow around a cylinder. I am having trouble understanding how to draw these. Any help is greatly appreciated! I ask this question because I am preparing for the Q exam for PhD and one of my classmates asked me about a Hele-Shaw flow: imagine two circular plates very close to each other (infinitely close). Now compare the streamlines of this Hele-Shaw flow and inviscid flow around a cylinder. Also draw lines of constant pressure for both cases. Evidently the streamlines looks identical but the pressure lines are different.