Research On Tesla Turbine Operational Performance And Structural Optimization Design

With the continuous changes in the world’s energy pattern,the original fossil energy on the earth is being consumed in large quantities,and the reserves of fossil energy can no longer support people’s long-term life.In the future,people will have difficulties in using insufficient energy.With the shortage of energy and the aggravation of environmental pollution caused by the use of energy,the efficient use of clean energy and renewable energy will become an extremely important research direction today and in the future.Most of the world’s area is the ocean,the ocean energy reserves are huge,and the use of ocean energy is very rich.Therefore,the rational and efficient use of ocean wave energy and the study of wave energy power generation devices will provide strong support for my country in the utilization of ocean energy.There are many islands in my country,and large-scale equipment power generation systems are time-consuming and labor-intensive to build,and the economic benefits of use on islands are not high.Therefore,the study of distributed power generation systems can supplement the shortcomings of large-scale power generation systems.Distributed power generation systems are relatively scattered and the size of the device Small,as a special turbine form,the Tesla turbine has a simple structure,low cost,and is easy to miniaturize,and has great potential for application in small and micro power generation systems.However,due to the low torque,high rotational speed during operation,and high requirements for materials,and the efficiency of large-scale equipment is not ideal,commercial applications have been limited since the development of Tesla turbines.In this paper,on the basis of the traditional Tesla turbine,by increasing the number of fluid inlet nozzles,changing the incidence angle of the nozzle,and studying the influence of the disc geometry on the operating performance of the Tesla turbine,the improved model of the Tesla turbine is proposed.One-dimensional and three-dimensional mathematical models were established.Through the established mathematical model,the fluid velocity and pressure distribution in the flow channel of the inner disc gap of the Tesla turbine can be calculated,and the torque,efficiency and output power of the Tesla turbine can be calculated through the mathematical model.Using "Fluent2021R1" to simulate the hydrodynamics of the single flow channel area between the Tesla turbine disks,changing the number of nozzles,the angle,and the ratio of the outer diameter to the inner diameter of the disk affect the fluid motion characteristics.Then,the effects of fluid inlet velocity,disk spacing,disk wall roughness,and disk edge shape on the three-dimensional flow field and the operating performance of the Tesla turbine were investigated.It is concluded that under the conditions permitting,the more the number of nozzles,the better,the distribution of the fluid in the disc gap is more uniform,and the fluid motion characteristics are better.When the angle of the nozzle is 15°,the fluid motion characteristics are better.;When the ratio of the outer diameter to the inner diameter of the disk is larger,the fluid moves on the disk with a longer path and transmits more energy;in the three-dimensional flow field,by changing the inlet velocity of the fluid,it is found that the higher the inlet velocity of the fluid is,the higher the rotational speed of the disc,the higher the output power and the operating efficiency;by changing the size of the disc gap,the operating efficiency at 0.3mm,0.6mm,0.9mm,1.5mm,and 2.5mm spacing was studied respectively.It is found that the efficiency of the Tesla turbine is the highest at 0.9mm,which can reach 53.33%;by changing the wall roughness of the disc and studying the operating performance of the Tesla turbine,it can be found that a small change in the roughness value will affect the Tesla.The operating efficiency of the turbine,but when the roughness value increases to a certain value,the operating efficiency increases to a stable range;then the shape of the edge of the disk is also studied,selecting rectangles,triangles and circles for research,and found that the disk When the edge shape is circular,the fluid has the best motion characteristics when entering the disk area,the occurrence of vortex phenomenon is the least,the energy loss is the least,and the output power and operating efficiency of the Tesla turbine are the best.On this basis,using the established mathematical model and the hydrodynamic analysis of the simplified model of the Tesla turbine,the Tesla turbine is preliminarily combined with the wave-gathering wave energy conversion device.The Tesla turbine was replaced,and the wave energy conversion device was selected at the same time,and the preliminary modeling was carried out by combining the two.The research of the paper shows that the Tesla turbine structure can be compact and miniaturized,the cost is low,and the efficiency is relatively high in the miniaturized equipment.It can be combined with the small wave energy equipment to explore the potential of the practical application of the Tesla turbine.