Alexandria Engineering Journal (Dec 2022)
Numerical simulation on fluid flow and temperature prediction of motorcycles based on CFD
Abstract
The temperature distributions of solid parts in motorcycle is of significance to give an quantitative cooling performance evaluation for assuring the feasible running of motorcycles. Therefore, the present work mainly tend to systematically investigate the flow velocity distributions and temperature distributions of motorcycle by constructing a fluid-solid coupling analysis model via CFD using commercial software STAR-CCM+. Based on computational fluid dynamics method (CFD), fluid-solid coupling analysis model of motorcycle is realized by integration of porous media model, heat exchanger model and fluid-solid co-simulation module and numerical investigations on fluid flow and temperature distribution characteristics at maximum running speed 120 km/h is conducted. The thermal management experiment test considering three pressure measuring points, fifty-eight temperature measuring points and two flowrate measuring points is investigated to know its cooling performance of motorcycle experimentally and provide experimental data for validation of simulation model. Results show that CFD results are in good agreement with experimental results and the maximum relative error is less than 10%. Thermal management test results show that left and right cylinder temperature, oil temperature are 183 °C, 190 °C, 120 °C, respectively. Air temperature of radiator at inlet side are from 29 °C to 35 °C, Air temperature of radiator at outlet side are from 60 °C to 90 °C, water temperature of radiator inlet and radiator outlet are 96 °C and 89 °C, respectively. The air temperature around left thigh and right thigh are 31 °C and 34 °C, respectively. CFD results show that there is no flow dead-zone and high temperature area in engine main components and muffler front cover. The temperature around motorcycle covering and both two thigh is not high due to the radiation of high-temperature components and the outlet temperature of exhaust muffler is also not high, which will not cause enough heat feelings to the riders for being uncomfortable. From the temperature field analysis results, there is no obvious poor temperature distributions for thermal comfort of this motorcycle. The results of this work can provide simulation data support and theoretical reference for the design and development of motorcycle and its crucial components. Through engineering applications of fluid-solid coupling model in a two-cylinder engine and electric generator, it verifies the universality of fluid-solid coupling model and it can be an effective way for the temperature predictions of industrial products.
