Abstract
Burn time errors caused by various start-up transient effects have a significant influence on the regression modelling of hybrid rockets. Their influence is especially pronounced in the simulation model of the Cascaded Multi Impinging Jet (CAMUI) hybrid rocket engine. This paper analyses these transient burn time errors and their effect on the regression simulations for short burn time engines. To address these errors, the equivalent burn time is introduced and is defined as the time the engine would burn if it were burning at its steady-state level throughout the burn time to achieve the measured total impulse. The accuracy of the regression simulation with and without the use of equivalent burn time is then finally compared. Equivalent burn time is shown to address the burn time issue successfully for port regression and, therefore, also for other types of cylindrical port hybrid rocket engines. For the CAMUI-specific impinging jet fore-end and back-end surfaces, though, the results are inconclusive.
Highlights
In recent years, there has been an increasing trend of development of new rocket systems using hybrid rocket technology [1]
This paper investigates the burn time errors associated with start-up transients
When focusing on the port surface regressions, the simulation results become as shown in Figure 8a for the analysis of 100 Lo data to simulate 100 Lo firing, Figure 8b for analysis of 100 Lo data to simulate 200 Lo firing, Figure 8c for analysis of 230 mm diameter high Reynolds number engine (230 Hi) data for 230 Hi simulation, and Figure 8d for analysis of 230 Hi data to simulate 200 Hi firing
Summary
There has been an increasing trend of development of new rocket systems using hybrid rocket technology [1]. Hybrid rockets are inherently safer than their liquid or solid counterparts as the fuel and oxidizer are in separate states, in this case, solid state and liquid state These separate states remove the possibility of uncontrolled mixing, and an explosion if any part of the engine ruptures [2]. Once the cost of the launcher hardware is low enough, the ground costs become the main expense, with a substantial part of this being due to the explosive nature of conventional solid and liquid bi-propellant rocket engines [3] Hybrid rockets avoid this cost but have traditionally had too low fuel regression rates and, too small thrust to weight ratios to be very useful as boosters
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call