QUESTION 1 An aircraft is delivered to Kemble airport to be dismantled for scrap. The fuel in the fuel tank needs to be drained but the fuel pump is unserviceable. An engineer suggests siphoning the remaining fuel. The piping arrangement is shown in Figure 1. The initial fuel height is Im in the tank. The siphon pipe is inserted 0.9m below the level of the fuel (point A). The other end of the siphon pipe (point C) is 2m below the bottom of the tank. Point B is the highest point of the pipe and located 5m above the level of the fuel. The specific gravity of the fuel is 0.78. The siphon pipe has a 20mm inner diameter. The barometric pressure is 756mm of mercury (whose density is 13600kg/m). Assume the tank wall thickness is negligible. a) Calculate the barometric/atmospheric pressure in Pascal. b) Calculate the total head at point A using point Cas a datum. c) Calculate the volumetric flow rate and time it would take to siphon the fuel out based on initial flow rate, if the remaining fuel in the tank is 3000litres. Internal fluid losses can be ignored. Hint : the fuel tank can be considered a reservoir. d) Before commencing the job, a health and safety inspection mandates that Point B shall to be raised to the height of the hangar which is 13m above the level of the fuel, whilst the outlet location does not change. How long will the tank now take to drain? Internal fluid losses can be ignored. e) For the scenario in parts a toc, determine the velocity of fluid accounting for the friction losses if the velocity without losses is &m/s (note that this is not necessarily the velocity for Q1c). The dynamic viscosity of the fuel is 1.5x10m/s. Use g-9.80665m/s B 5m 0.9m 1m A 2m Figure 1. Tank and piping arrangement for siphon Page 2 of 5