CAJ | 학술논문

以实验数据和理论结果作为参考,探讨基于布茨涅克各向同性假设的RNG k-ε模型、SST模型和各向异性RSM湍流模型在双向涡流数值计算中的适用性,并对不同入射速度下的双向涡流结构进行了比较分析. 计算结果表明,基于布茨涅克各向同性假设的RNG模型与SST模型在不同入射速度下均无法得到内部受迫涡、外部自由涡的双向涡流结构,而RSM模型则可以准确得到双向涡流结构. 内、外涡分界面处雷诺正应力各向异性特征显著,且随入射速度的提高而增强,最大差值达到了198%,轴线附近流场雷诺正应力各向异性特征相对较弱,但是最大差值依然达到46%,因此基于布茨涅克各向同性假设的湍流模型不适用于涡流冷壁发动机数值模拟研究.
이실험수거화이론결과작위삼고,탐토기우포자열극각향동성가설적RNG k-ε모형、SST모형화각향이성RSM단류모형재쌍향와류수치계산중적괄용성,병대불동입사속도하적쌍향와류결구진행료비교분석. 계산결과표명,기우포자열극각향동성가설적RNG모형여SST모형재불동입사속도하균무법득도내부수박와、외부자유와적쌍향와류결구,이RSM모형칙가이준학득도쌍향와류결구. 내、외와분계면처뢰낙정응력각향이성특정현저,차수입사속도적제고이증강,최대차치체도료198%,축선부근류장뢰낙정응력각향이성특정상대교약,단시최대차치의연체도46%,인차기우포자열극각향동성가설적단류모형불괄용우와류랭벽발동궤수치모의연구.
In this paper,simulation results were compared with experimental data and theoretical results.The simulation validity of RNG k-ε model and SST model based on Boussinesq isotropic hypothesis and RSM model in bidirectional vortex were discussed and bidirectional vortex properties in different inlet velocities were analyzed as well. It is pointed out that the RNG model and SST model could not achieve the bidirectional vortex which frees in outer area and is forced in inner space under any inlet velocity based on Boussinesq isotropic hypothesis,while the RSM model simulation results fit the experiment data and theoretical solutions well.In mantle surface of inner vortex and outer vortex,Reynolds stress anisotropy characteristics is significant and is strengthened with the increase of inlet velocity.The biggest difference between normal stresses in x,y,z direction can reach up to 198%.In core flow area close to axial,Reynolds stress anisotropy is relatively weak,but the greatest difference can still reach as large as 46%.Therefore,it is believed that turbulent models based on Boussinesq isotropic hypothesis are invalid in VCCWC simulation.