Optimal Design Of High-power-density Hydraulic Manifolds Utilizing Additive Manufacturing

Fluid power is a transmission method that uses liquid as the working medium,and it has been widely utilized in engineering machinery,aerospace,robotics and other fields by advantages of high power-to-weight ratio.Facing the need for miniaturization and integration of hydraulic systems,it is a hotspot to increase the power density to achieve a wider application of hydraulic systems in the field of mobile robotics and aerospace.The hydraulic manifold,one of important parts in a hydraulic system,is large in size and heavy in weight,and the pressure loss inside the manifold is severe,which limits the improvement of the power density of the hydraulic system.Combined with the unprecedented freedom of additive manufacturing,it can be optimized in such a way that cannot be achieved by traditional fabrication methods.This subject focuses on the AMed hydraulic manifold block,in which a smooth transition structure is applied to replace the sharp-angle flow channel.Numerical and experimental research was carried out to investigate the mechanism of pressure drop in a manifold,and some optimized structures were used to replace the original one accordingly.Meanwhile,the Response Surface Methodology(RSM)is adopted to perform local optimization of different flow channels.An optimization selection is realized,and the optimal performance under different working conditions is guaranteed.Taking the technical limitations of AM technology,especially Selective Laser Melting(SLM),the influence of the manufacturing process like build orientation on the part properties was explored.To address its problems,special cross-section channels were designed and the geometrical accuracy and surface roughness were clarified.Furthermore,the parameters of the process were optimized to realize a better build quality.The internal and external heat transfer performance improvement technology was investigated,in order to achieve a good integration of lightweight design and heat dissipation functions.According to the changes in the working environment and the actual needs of forced convection,the hydraulic manifolds under different working modes can be changed,and the manifolds are designed from a single part to be assemblable to achieve good adaptability to various working environments.