氢能是一种清洁能源。氢能源系统中高温高压部件的可靠性是系统安全高效运行的关键，高温高压含氢混合物密度及黏度的精确测量对于系统的设计和优化具有重要意义。本文测量了高温高压含氢混合物的密度及黏度，建立了计算模型。针对高温高压下含氢混合物是否均相的问题，基于立方型状态方程计算了CH4?C2H6、H2?CO2、H2?CH4和H2?CO混合物的相平衡与H2?CO2、CO2?H2O系统的临界线，与实验值符合，验证了计算方法的可行性；对H2?CO2−CH4?CO−H2O体系均相区及临界点的计算结果表明体系在本文实验温度压力范围内处在均相区。针对经典膨胀法密度测量在573 K以上阀门泄露的难题，提出了一种改进膨胀法，将阀门及管路置于较低且保证样品均相的温度，设计并搭建了实验装置，使用N2在353?923 K、He和H2在673 K测量校验了仪器的可靠性，测量了673 K，0?25 MPa下H2?CO2和H2?CO2−CH4混合物的密度，扩展相对不确定度(k = 2)为0.008。针对膨胀法在高温下测量中氢渗透及化学反应影响较大的问题，设计并搭建了定容法测量高温高压流体密度的实验装置，使用H2O、N2和H2在722?927 K测量标定仪器并校验了仪器的可靠性，测量得到了722?930 K，15?31 MPa下H2?CO2−CH4?CO−H2O体系的密度数据，扩展相对不确定度(k = 2)为0.0125。基于实验密度数据计算了N2、He和H2在353?923 K的维里系数，与标准值符合较好。基于实验密度数据计算了H2?CO2和H2?CO2−CH4混合物在673 K的维里系数和相互作用维里系数。针对多元含氢混合物pVT模型中相互作用维里系数较多且难于定性正负值的问题，建立了高温高压H2?CO2−CH4?CO−H2O体系的维里型状态方程，对722?939 K、最高35 MPa的密度计算值与实验值的偏差小于1.5%。针对微管法黏度测量中金属微管高温易失效的问题，设计并搭建了采用石英微管两相进样的装置，通过对H2O、N2和H2在279?979 K的测量验证了其可靠性，测量了H2?CO2、H2?CO2−CH4、H2?H2O混合物和H2?CO2−CH4?CO−H2O体系在280?924 K、0?34 MPa的黏度，动力黏度的扩展相对不确定度(k = 2)为0.05。建立了考虑非理想气体效应的黏度计算模型，黏度计算值与实验值的偏差小于5%。

Hydrogen energy is a kind of clean energy. The reliability of the high-temperature and high-pressure parts in the hydrogen energy systems is crucial to the safe and efficient running of the systems, and the precise measurement of the density and viscosity of hydrogen-containing mixtures is significant for the design and optimization of the hydrogen energy systems. In this thesis, the density and viscosity of hydrogen-containing mixtures at high temperatures and high pressures were measured, and the theoretical models for calculating the density and viscosity of hydrogen-containing mixtures at high temperatures and high pressures were developed.To answer the question whether the hydrogen-containing mixtures at high temperatures and high pressures are homogeneous, the phase equilibria of the CH4?C2H6, H2?CO2, H2?CH4, and H2?CO mixtures and the critical curves of the H2?CO2 and CO2?H2O mixtures were calculated based on the cubic equations of state. The calculated values agreed with the experimental values, which validated the feasibility of the method. The calculation results of the stability limits of temperature and pressure and the critical points of the H2?CO2−CH4?CO−H2O system indicated that the temperatures and pressures of the experiments in this thesis were in the stable region.A modified Burnett method for measuring the density of gases was developed to solve the problem of gas leakage at the valves at above 573 K in the classical Burnett method. The valves and tubes were maintained at a lower temperature which could also guarantee the homogeneity of the sample. The apparatus of the modified Burnett method was designed and built. The reliability of the method and apparatus was validated by the measurements of N2 at 353?923 K and of He and H2 at 673 K. The densities of the H2?CO2 and H2?CO2−CH4 mixtures were measured at 673 K and 0?25 MPa with the combined expanded relative uncertainty (k = 2) of 0.008.An isochoric apparatus for measuring the density of fluids at high temperatures and high pressures was designed and built to solve the problems of hydrogen permeation and chemical reactions at high temperatures in the Burnett density measurements. Measurements of H2O, N2, and H2 at 722?927 K were carried out to calibrate the apparatus and validate the reliability of the apparatus. The densities of the H2?CO2−CH4?CO−H2O system were measured at 722?930 K and 15?31 MPa with the combined expanded relative uncertainty (k = 2) of 0.0125.The virial coefficients of N2, He, and H2 at 353?923 K were calculated using the experimental density data and they agreed with the reference values. The virial coefficients and interaction virial coefficients for the H2?CO2 and H2?CO2−CH4 mixtures at 673 K were calculated using the experimental density data. A virial equation of state for the H2?CO2−CH4?CO−H2O system at high temperatures and high pressures was developed to solve the problem of determining the signs of the numerous interaction virial coefficients. The absolute relative deviations of the calculated density values at 722?939 K and up to 35 MPa from the experimental values were less than 1.5%.A capillary apparatus for measuring the viscosity of fluids at high temperatures and high pressures using quartz capillaries and two-phase inlets was designed and built to solve the problem of the easily failure of the metallic capillaries at high temperatures. The reliability of the apparatus was validated by the measurements of H2O, N2, and H2 at 279?979 K. The viscosities of the H2?CO2, H2?CO2−CH4, and H2?H2O mixtures and the H2?CO2−CH4?CO−H2O system were measured at 280?924 K and 0?34 MPa. The combined expanded relative uncertainty (k = 2) of the measured dynamic viscosities was 0.05. The viscosity calculation model for the hydrogen-containing mixtures considering the non-ideal gas effect was developed. The absolute average deviation of the calculated dynamic viscosities from the experimental values was less than 5%.