In the study of hydrogen economy

the thermophysical properties of normal hydrogen are required to simulate a hydrogen system

including the thermodynamic properties

such as heat capacity and vapor pressure

and transport properties

such as thermal conductivity and viscosity.The thermal conductivity has a large effect on the heat transfer characteristics

which

in turn

greatly impact the cost and economic feasibility of the hydrogen system.Hence

a new equation for thermal conductivity of normal hydrogen(25% parahydrogen)is proposed by fitting extensive experimental data using a simplex method in this work.The deviations between the values calculated by the equation and the experimental data are generally less than 5.0%.The valid range of the equation is from 100 K to 500 K at pressures up to 150 MPa

and the uncertainty of the equation is estimated to be 3.0%. The extrapolation of the equation is reasonable

so the equation can be used at temperatures below 100 K or from 500 K to 1000 K at pressures up to 250 MPa.