Influence of Rectifier Nozzles on the Flow Distribution Characteristics of Parallel Pipes

Abstract

The inhomogeneous distribution of parallel pipe flow leads to difficulty in the efficient and reliable operation of fluid power equipment. In view of this, a new type of rectifier nozzle has been proposed in parallel pipelines. Numerical simulation and experimental studies were used to reveal the influence of the rectification nozzle on the flow distribution characteristics. The hydraulic characteristics of the parallel pipelines with and without rectifier nozzles were compared and analyzed. The effects of the temperature and inlet flow on the flow uniformity were studied. The results showed that the initial temperature had little effect on the flow distribution of parallel pipelines, and the flow rates of the branches were not much different. The inlet flow had great influence on the distribution characteristics of the parallel pipelines, but the rectifier nozzles changed the local resistance structure and pressure distribution at the shunt, thereby improving the non-uniformity of the flow distribution of the parallel pipelines, and the maximum difference between the two pipes was optimized from 28.89 t/h (20.3%) to 2.2 t/h (1.5%). The rectifying nozzle could distort the flow field of each branch during the split, making the distribution of flow rate and flow state more uniform and stable. At high inlet fluid temperatures, cavitation could occur under the pressure drop of the nozzle, and partial cavitation had little effect on the flow distribution.

Optimization design of flow distribution manifold structure in fuel cell engine cooling system

“…In theory, the flow distribution in parallel pipes is influenced by the resistance along the pipe and local resistance [6], and the flow losses of each branch in the parallel pipes in the cooling system are equal [7]. The flow distribution in the system is affected by both the branching and merging of cooling water in the pipes and the resistance.…”