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This paper studies the temperature field, dynamic strain and forming accuracy of the Oscillate-WAAM conical shell in the forming process and manufactures the WAAM conical shell part. The results show that compared with the offset filling WAAM, the oscillate-WAAM conical shell shows the following characteristics：the temperature difference value between the inner and outer walls of the shell is significantly reduced, the cooling rate doubled decreased, the interlayer temperature is above 300°C, as well as the average temperature gradient, the dynamic strain stability value and deformation are reduced by about 50%. Under the same process parameters, the travel speed of Oscillate-WAAM is low, which increased the heat input large and the interlayer temperature high. Meanwhile, the molten pool of Oscillate-WAAM is in consistent with the width of the shell. The molten pool simultaneous solidifying changes the stress state of printed shell form three-dimensional to two-dimensional. All above are conductive to stress release, and reduce the strain and deformation of components. The bimetallic rocket motor shell composed of HS600 and HS950 is manufactured by oscillate-WAAM. The section roundness of the shell is 0.31mm and the overall forming accuracy is ±0.625mm. The deposited metal in HS600 part of conical shell is composed of pearlite and pro-eutectoid ferrite. While the deposited metal of HS950 is composed of pearlite, acicular ferrite and bainite. The forming accuracy and mechanical properties of conical shell formed by Oscillate-WAAM meet the requirements.

In the present paper, an improved multiphase weakly compressible smoothed particle hydrodynamics model for balancing the accuracy and stability of the long‐term simulations is proposed to model the forced liquid sloshing in a tank. The governing equations of the multiphase flow are discretized by considering the density discontinuity over the interface. To suppress the pressure oscillation, a previous density correction term suitable only for single‐phase problems is modified and incorporated into the discrete continuity equation to suit multiphase problems. The modified density reinitialization algorithm is implemented to calculate the pressure of the boundary particles, and the coupled dynamic solid boundary treatment (SBT) is employed to determine the rigid wall condition. For convenience, a numerical probe algorithm is also proposed to accurately measure the wave height. The present model exhibits a better numerical stability than the previous multiphase smoothed particle hydrodynamics model, and its results well confirm with the experimental data of the forced sloshing of liquid excited by swaying or rolling.