Answer Happy

(a) Describe with the aid of sketches two types of surge tanks used to improve the degree of damping. (b) An oil company wishes to construct a pressurised pipeline of 300 mm diameter to convey freshwater, of bulk modulus 2.10x10 N/m2 from a desalination plant to a refinery at a rate of 350 l/s and with a pipe period of 4 seconds. Calculate the corresponding theoretical surge pressure induced within the pipeline by the complete closure of an on-line valve in 8 seconds. The valve generates non- uniform retardation of type R = At0.85. The steel pipe has 5 mm thick walls, a Young's modulus of 2.1x1011 N/m2 and Poisson's ratio of 0.28. Calculate the pressure transients at 1 second intervals for the mid-point of the pipeline, for the first 12 seconds after the valve starts close. Assume that pipe is longitudinally restrained.