Development of CAMUI hybrid rocket to create a market for small rocket experiments

Abstract

By introducing various innovative ideas, the difficult-to-develop small hybrid-type rocket is successfully developed. The main purpose is to drastically reduce the cost of rocket experiments and thus attract potential users such as metrological and microgravity researchers. A key idea is a new fuel grain design to accelerate the gasification rate of solid fuel. The new fuel grain design, designated as CAMUI as an abbreviation of "Cascaded Multistage Impinging-jet", is that the gas flow repeatedly collides with the solid fuel surface to accelerate the heat transfer to the fuel. To install a regenerative cooling system using cryogenic liquid oxygen as coolant in a small launcher, the authors devised a valveless supply system (with no valves in the liquid oxygen flow line). Four serial successful launch verification tests by 10 kg vehicle equipped with a 50 kgf thrust CAMUI motor have shown the feasibility of the motor system. The meteorological observation model of 400 kgf class motor is under development and the development of microgravity experiment class of 1.5 to 2 tonf motor will follow subsequently. The authors plan to complete the development of the 400 kgf class motor for meteorological observation model by the end of FY2005.

Research Activities of Advanced Propulsion Technology in JAXA

“…To modify the design technology of the ejector system, subsonic/transonic flight tests are planned by the CAMUI hybrid rocket 12 with Hokkaido University. In the tests, the ejector performance in the subsonic/transonic conditions is measured with an ejector rocket engine based on the original CAMUI rocket engine.…”

Development of Wall Regression Model of Hybrid Rocket Solid Fuel

“…[2] Calculate the heat flux from the gas to the wall. [3] Estimate the amount of regression. [4] Change the wall shape.…”

“…To resolve this problem, several new ideas have been proposed and/or developed, such as a swirling-oxidizer-type or cascaded multistage impinging-jet (CAMUI) type. [1][2][3] In a combustion chamber of a hybrid rocket engine, the channel wall surrounding the combustion field is a solid fuel. The shape of the flow field changes depending on the regression and vaporization of the solid fuel.…”

Kinetic modelling of High Density PolyEthylene pyrolysis: Part 2. Reduction of existing detailed mechanism

“…This is a coupled system which deserves to be studied numerically to investigate in details the way the fuel is pyrolysed to produce the species which diffuse from the solid surface to the gas flow. While experiments from lab scale to full scale with firing conditions do exist [5], [6], numerical modelling often remains limited in terms of chemistry because the fluid mechanics description is favoured [7], [8].…”