Modeling And Optimization Of Electrolyte Distributor For Silver-Zinc Battery

Silver-zinc battery has been used on naval vessels for more than 50 years, for its some special characters, such as high energy ratio, plat voltage curve, safety, reliability and etc. It is popularly used on blue water vessels now. After experimental analysis, a result comes out that most of the battery groups' invalidation due to some single battery's lack of electrolyte, so the groups' capability were limited by some single battery. For most battery groups, uniform section distributor systems are used. During the distributing process, batteries farther from the chief inlet will be injected more electrolyte because of the pressure change, the end battery has the most income, capability differences among batteries are significant.The main work of this paper is modeling and optimization of electrolyte distributor for silver- zinc battery, the program was divided into two parts: electrolyte injection speed and electrolyte distribution uniformity. Electrolyte injection speed modeling includes electrolyte injection and the steel container's deflation; electrolyte distribution uniformity modeling is about the electrolyte's distribution among single batteries.The VOF model in FLUENT can solve the speed modeling and uniformity modeling well. In the results, we can see that 95% electrolyte can be injected into batteries in 0.75 s, it fits the request of speed modeling. In 2 minutes, the pressure in steel container will decrease from 1.5MPa to 0.1MPa, it also works fit the requirements. To three dimension battery, the time of injecting 5.74L electrolyte to single batteries is about 0.7s, it works well, but the electrolyte volume in the front 18 batteries are little, and large differences exist among the batteries, it doesn't fit to the uniformity requirement.So the optimization is needed. First, the direction of main inlet should be changed, parallel to the main pipe will make less momentum loss, and electrolyte distribution equality become better. Then we also got better results on electrolyte distribution equality by using two inlets and subulate main inlet models. So using two inlet and subulate main inlet together will work better. The results in the paper show that the model using two inlet and subulate main inlet together got a better electrolyte distribution uniformity than using singly. In the end, for the purpose of being closer to the actual model, the couple effect of electrolyte injection and electrolyte distribution was considered. VOF model and dynamic grid technology were used to model the actual system working process. Dynamic electrolyte injection and electrolyte distribution process can be seen easily.