662. A Semi-Empirical Method for Propellant Tank Weight Estimation

Paper

Abstract

This report presents information on a semi-empirical method for obtaining a quick and realistic tank weight for nine common configurations. An empirical weight equation is included for both pressure-fed and pump-fed systems. The equation for the pressure-fed system is based on limited data, but does have the correct relationship to the turbopump-fed system equation.
General formulae, based on tank geometry and pressure effects, by which a amore detailed tank weight analysis may be performed, are also presented. The information contained in a table of general formulae permits weights to be calculated for any tank configuration except torodial. Data necessary for determining tank design pressured based on propellant characteristics and flow rate, engine performance parameters, plumbing geometry, and missile trajectory is also included. The empirical weight increment is divided into a number of nonoptimum factors to permit a separate analysis of some of these items if sufficient data are available. Separate analysis of tank cylindrical sections may be performed by utilizing the included curves for pressure-stabilized cylindrical shells subjected to axial loads and bending moments.