A multistage dynamic computer model has been developed for the simulation of the performance of entrainment coal gasification. The model provides for the calculation of such pertinent factors as reaction rates, physical properties of solids and gases, transport coefficients, devolatilization, effect of the type of reactor, etc. The profiles of rate-variables such as gas mixture and particle temperatures, carbon conversion, and gas composition, were tracked against time of operation by numerical integration. After a great deal of time has been consumed to assure the stability of the program, efforts were spent to compare the simulated results with experimental data both from Homer City, Pennsylvania for the Bigas reactor and from Mountain Fuels, Utah. 13 refs., 16 figs., 15 tabs.