液化石油气自然气化量的数值模拟

根据液化石油气自然气化的相变传热过程，应用传热传质的基本方程，导出了储罐气化规律的微分方程组。采用数值积分法，根据储罐容积、液化石油气质量、组成、环境温度等条件计算其气化参数。     

液化石油气瓶组气化供气系统的安全分析

分析了液化石油气瓶组气化系统存在的不安全因素、产生的原因、造成的后果，探讨了采取的对策。     

Thermodynamic characteristics of vaporization of alkali metals

The saturation vapor of an alkali metal is treated as a monatomic particle real gas whose volumetric behavior is described by a truncated form of virial equation. The condensed state-vapor equilibrium constant, equal to the saturation fugacity for Li, Na, K, and Cs, is determined through evaluation of the second virial coefficient's temperature dependence. The third and the second law values of standard enthalpy of vaporization at the reference temperature 298 K for the same metals are determined. The applied procedure for evaluation of the second virial coefficient's temperature dependence produced small deviations for the resulting second law values and gave mean values in good agreement with literature data, especially with those of the JANAF Tables.     

Enthalpies of vaporization of oligomers of poly(hexamethylene sebacate) and esters of alkylcarboxylic acids

Enthalpies of vaporization for esters covering a molecular weight range of about 74–939 g/mol · [monocarboxylics; linear esters of sebacic series; branched esters of triglyceride series; and, oligomer esters of poly(hexamethylene sebacate)] and a temperature range of about 273.15–523.15 K have been empirically fitted to within about 5% to an equation of the following form: ΔHv(T,M) = S(T)f(M) + I₀(T), where S(T) = C Ln(T) + K₀, I₀(T) = aT + b₀, and f(M) = M/(1 + a₀M), M is the molecular weight (molar mass); T is in degrees Kelvin; and, C, K₀, a, b₀, and a₀ are constants. These results were used to determine the heat capacity difference, ΔC_p = C_p(l) − C_p(g), and compared to calculated values from functional relationships of C_p(l) and C_p(g), l is liquid g is gas. The heat capacity difference results in conjunction with C_p(l) were used to empirically calculate the heat capacity of the gas, C_p(g), over the molecular weight and temperature ranges investigated and compared to a group contribution method. The functional forms for ΔHv(T,M), ΔC_p(T,M), C_p(l), and C_p(g) were also found to be applicable for n-alkanes. © 1998 John Wiley & Sons, Inc. J. Appl. Polym. Sci. 70: 731–746, 1998     

气化器后气态液化石油气带液的解决方案

分析了液化石油气混空气生产中液化石油气气化器后气态液化石油气带液的原因,提出了气化器温度控制、气化器后管道保温等技术措施。     

调节阀汽蚀现象的分析与控制

分析了汽蚀的产生原因和给调节阀带来的影响与危害，介绍了有效防止汽蚀破坏阀门的方法，以延长阀门的使用寿命，保证阀门的可靠性能。     

液化石油气泡点的直接计算及其应用

讨论了泡点的计算方法,提出了泡点的直接计算公式,介绍了泡点在气化器研究中的应用。     

Drawbacks of phase change models in simulating flashing of steam with a subsaturation downstream boundary condition

The development of phase change models applicable to a wide range of temperatures, pressures, and mass flow rates is primarily limited by the metastable or partially stable behaviour of the fluid. Due to this, the fluid does not change phase even after crossing saturation conditions. Most liquid–vapour phase change models have been developed primarily for the cavitation process where the phase change is not sustained, occurs in a very narrow region of space, or occurs under equilibrium conditions. In this paper, the mechanism of phase change is discussed along with the review of three different computational fluid dynamics (CFD)-based phase change methods available in OpenFOAM, which are used to simulate flashing of steam, in applications related to steam assisted gravity drainage (SAGD) systems. The first method is based on barotropic compressibility (BC) used with the realizable $k-\epsilon$ turbulence model, the second combination is of mass transfer model (MTM) with the realizable $k-\epsilon$ turbulence model, and the third one is based on two fluid (TF) method along with a family of $k-\omega$ turbulence models. These methods are tested on a converging–diverging nozzle with pressure driven phase change. It is demonstrated that these methods are not able to adjust their physics to different depressurization rates, do not account for liquid to be in superheated conditions, and have significant discrepancies with experimental results. In the end, better approaches to model this category of phase change are discussed.