Technical Reports

Development of a Computer Program for Modeling the Heat Effects on a Railroad Tank Car

  • 01
  • Jan
  • 1973
AUTHOR: K.W. Graves
SUBJECT: Hazardous Materials
KEYWORDS: tank car; liquefied petroleum gases, heat transfer, self-pressurization
ABSTRACT: A mathematical model has been programmed in FORTRAN IV that represents the response to a fire environment of a railroad tank car laden with a volatile, flammable fluid. Inputs to the program include total mass of lading per foot of tank length, tank length, number and flow area of relief valves, their opening and closing pressure, thickness and thermal conductivity of exterior insulation, an array of the thermodynamic properties of the lading, its initial condition, and heat transfer coefficient and fire temperature at various points on the tank. Output includes tank pressure, temperatures of the liquid and vapor, temperatures of the interior surface of the shell, mass of liquid remaining, and location of the liquid level. These are printed for the end of every computing interval, thus indicating the history of each. Computer solutions have been obtained using input data representing problems for which explicit solutions are available and good agreement was achieved. Attempts to represent fire tests were not completely successful but computer results are encouraging. Recommendations are made for further improvements, some of which require more fire tests data.