Numerical EES Code of Liquid Piston Hydrogen Compression ,and hydrophobic thermophysical properties of some ILs_2026 Data sets
Description
This dataset contains an Engineering Equation Solver (EES) model of a single-stage liquid piston compressor for hydrogen gas. The model simulates the transient compression process inside a cylindrical chamber where a liquid piston compresses hydrogen while accounting for energy balances, Convection-based heat transfer at the liquid–gas interface, and wall heat transfer through finite-difference discretization. The code numerically solves the coupled mass and energy balance equations for the gas, liquid, and chamber wall over a defined time domain. The primary objective of the model is to evaluate: Gas pressure evolution during compression Gas temperature rise during compression Heat transfer at the liquid–gas interface (conduction only) Thermal interaction between working fluid and vessel wall Thermodynamic behavior of hydrogen under compression
Files
Steps to reproduce
The dataset contains thermophysical property correlations and thermodynamic modeling data for an ionic-liquid piston compressor using 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([EMIM][Tf₂N]). The thermophysical properties (density, viscosity, specific heat capacity, and thermal conductivity) were obtained from peer-reviewed literature sources and validated databases, then correlated as functions of temperature and pressure using nonlinear regression analysis. Curve fitting was performed in Engineering Equation Solver (EES, F-Chart Software) employing least-squares optimization to determine empirical coefficients for temperature- and pressure-dependent property equations. These correlations were implemented within a thermodynamic compression model developed in EES to simulate transient hydrogen compression in an ionic-liquid piston configuration. The model solves mass and energy balance equations for a control volume under polytropic/real-gas conditions, incorporating hydrogen property routines available in EES and the fitted ionic-liquid property correlations. Simulations were conducted over a pressure range of 100–700 bar and time steps of 0.5–5.0 s to generate outlet temperature and performance data. The shared materials include the fitted correlation equations, regression outputs, and the complete EES source code to ensure reproducibility of the thermodynamic calculations and compression process simulations