Cylinder head hydropulse fatigue test method

Abstract: To be able to verify that a cylinder head design meats the expectations a good test method is needed. The aim of this thesis is to determine the best way of testing with respect to validity, cost, time consumption, quantity of tested material and repeatability. The base of the new method is the current single head method and this have been expanded to the suit the cylinder head of a seven litre engine currently in production. In order to determine how many cylinders to test and the order of these simulations of fatigue have been performed. Comparing these different ways of testing was done with a comparison of the safety factor against fatigue in a reference case composed of the ignition sequence and 17 feasible test methods. From the simulation results two suitable test fixtures have been designed in Catia. A method composed of two phases of pulsation with cylinders 1, 3 and 5 in the first phase and 2, 4 and 6 in the second phase is suggested as test method.