QUESTION 5 15 marks A projectile is being tested to determine its drag when passing through air with density p = 1.2kg.m? To do this, engineers have employed a flow visualisation technique so that they can determine the velocity profile upstream and downstream of the projectile. The profile upstream is uniform at a speed V = 200ms; the profile downstream is steady and varies linearly from a flow speed of zero (relative to the projectile) at the centre axis to a streamline at a radius of 3cm. The pressure upstream is atmospheric, and downstream is 5kPa-absolute. Define and sketch a suitable control volume for a momentum conservation analysis Find the average velocity at the downstream point and the velocity at the streamline at r = 3cm Find the force exerted on the projectile. r=3cm r=lcm QUESTION 5 15 marks A projectile is being tested to determine its drag when passing through air with density p = 1.2kg.m? To do this, engineers have employed a flow visualisation technique so that they can determine the velocity profile upstream and downstream of the projectile. The profile upstream is uniform at a speed V = 200ms; the profile downstream is steady and varies linearly from a flow speed of zero (relative to the projectile) at the centre axis to a streamline at a radius of 3cm. The pressure upstream is atmospheric, and downstream is 5kPa-absolute. Define and sketch a suitable control volume for a momentum conservation analysis Find the average velocity at the downstream point and the velocity at the streamline at r = 3cm Find the force exerted on the projectile. r=3cm r=lcm