Molecular diffusion and phase stability in high-pressure combustion
Molecular diffusion and phase stability in high-pressure combustion
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高压燃烧中的分子扩散和相稳定性
DOI：
10.1016/j.combustflame.2019.08.036
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发表时间：
2019
影响因子：
4.4
通讯作者：
M. Ihme
中科院分区：
文献类型：
--
作者：
Matthew X. Yao;Jean;P. Ma;M. Ihme
模拟火箭发动机高压燃烧所需的建模复杂性的增加导致了显着的计算成本-成本并不总是合理的工程应用。对于最简单的氢/氧燃烧，多组分扩散计算比恒定刘易斯数扩散假设至少贵40%;计算代价随着所考虑的物种数迅速增加。在低温燃料燃烧中，如果扩散影响推进剂的相稳定性，则更高保真的扩散模型是合理的。我们调查的混合物平均，多组分，和恒定的刘易斯数扩散模型的层流逆流火焰在跨和超临界条件下的典型火箭推进剂，即：氢，甲烷和煤油的影响。使用汽液平衡（VLE）理论，我们表明，即使在极限情况下，质量扩散模型的相稳定性和伪相变化的推进剂的影响有限;大多数的微分扩散误差位于高温/理想气体区域的火焰。由真实的流体热力学引起的微分扩散误差最多约为在火焰的理想气体区域中出现的微分扩散误差的20%。因此，差分扩散的影响仍然类似于低压燃烧条件，从而支持使用工程级简化这些复杂的高压反应流的模拟。
The increased modeling complexity needed to simulate high-pressure combustion in rocket engines results in significant computational costs–costs which are not always justified for engineering applications. Multicomponent diffusion computations are at least 40% more expensive than the constant Lewis number diffusion assumption for the simplest hydrogen/oxygen combustion; the computational penalty increases rapidly with the number of species under consideration. The higher-fidelity diffusion modeling is justified in cryogenic fuel combustion if it affects the phase-stability of the propellants. We investigate the impact of the mixture averaged, multicomponent, and constant Lewis number diffusion models of a laminar counterflow flame at trans- and supercritical conditions for typical rocket propellants, namely: hydrogen, methane, and kerosene. Using vapor liquid equilibrium (VLE) theory, we show that, even in the limit cases, the mass diffusion model has a limited effect on the phase stability and pseudo-phase change of the propellants; the majority of the differential diffusion errors are located in the high temperature/ideal gas regions of the flame. The differential diffusion error due to real fluid thermodynamics is at most about 20% of the differential diffusion error which occurs in the ideal gas region of the flame. As a result, the impact of the differential diffusion remains similar to low-pressure combustion conditions, thus supporting the use of engineering-level simplifications for the simulation of these complex high-pressure reactive flows.
高压条件下非预混燃烧的高效热化学表格
DOI：
10.1007/s10494-018-9932-4
发表时间：
2018
期刊：
Flow, Turbulence and Combustion
影响因子：
--
作者：
Zips J;Müller H.;Pfitzner M.
通讯作者：
Pfitzner M.
影响因子：
4.4
作者：
E. Richardson;Jacqueline H. Chen
通讯作者：
E. Richardson;Jacqueline H. Chen