A simplified one-dimensional transient heat transfer model for rocket thrust chamber

Abstract

The heat transfer model is essential to rocket engine thrust chamber, for it determines the accuracy of chamber wall temperature and heat flux distribution. In order to predict the transient temperature field during startup and shutdown, we introduce a simplified one-dimensional model of transient heat transfer for thrust chamber. The heat transfer process is divided into two parts: the convective heat transfer from hot gas to the inner wall and the heat conductance through the chamber wall. The Bartz formula modified with constant coefficient C is used to characterize the convective heat transfer and the one-dimensional transient heat transfer model of slab is the calculative foundation of the heat conductance. Finally, we propose a strategy to iteratively solve the model. To verify the model, it is implemented in a series of hot run experiments for a LOX/Methane heat sink thrust chamber. The average error of wall temperature evaluated at different locations of the thrust chamber inner wall can be reduced up to a 1.76%. The application of our novel method provides an accurate and efficient tool to calculate chamber wall temperature and heat flux distribution in the thrust chamber design. In addition, through inverse analysis of the proposed model, we can also estimate the near-wall gas temperature, which is difficult to obtain in a hot run test, by acquiring wall temperature data.