Arcjet rocket

About: Arcjet rocket is a research topic. Over the lifetime, 1121 publications have been published within this topic receiving 9687 citations. The topic is also known as: Arcjet.

Evaluation of Prediction Accuracy of Thermal Response of Ablator Under Arcjet Flow Condisions

Abstract: Using a cloth-layered carbon fiber reinforced plastic ablator with a specific gravity of about 1.5, the thermal response model of ablator is studied experimentally and numerically. Heating tests are carried out in the arcjet wind tunnel to quantify the thermal performance of ablator. In the tests, the surface temperatures and in-depth temperatures of ablative test pieces are measured during the testing. The experimental results obtained in the heating tests are analyzed by using a two-dimensional analysis method developed earlier. In the method, the thermal response of ablator is calculated by loosely coupling the shock layer computational fluid dynamics code and the 2-D version of ablation code using an arcjet freestream condition. The arcjet freestream condition in the test section is evaluated by calculating the flows in the arcjet wind tunnel. The present analyses are made especially focusing on an anisotropic nature of thermal conduction of ablator. Thermal conduction inside the ablator is modeled in the present analysis method based on thermal conductivity values measured for different ply angles of carbon cloths of ablator. By comparing the calculated results with the arcjet data, the prediction accuracy of thermal response models of ablator is discussed.

Transient heat-transfer analysis of a conical cathode of an MPD arcjet

Abstract: Most magnetoplasmadynamic thrusters operate with high temperatures at the cathode root in order to allow the emission of electrons with a moderate electric field while suffering minimum material loss. Attention is presently given to a two-time level implicit scheme for the numerical solution of the nonlinear transient energy equation of a conical cathode. The scheme is simple, unconditionally stable, and convergent. 7 references.

Conceptual spacecraft and arcjet propulsion system design for the SP-100 interim reference mission

Abstract: An arcjet propulsion system, delivering 7.5 N thrust, was defined for the SP-100 Space Reactor Power System Interim Reference Mission. Conceptual design trades and configuration studies of a spacecraft suitable for the mission were performed to the extent necessary to define propulsion system requirements and interfaces. The propulsion system design is based on the use of 30-kW, constricted arc, ammonia arcjet engines operating in parallel during orbit boost from low earth to geosynchronous orbit.

Two-Dimensional LTE Modeling of a Low-Power Argon Arcjet Thruster

Abstract: The extension to a higher specific impulse of an arcjet requires deeper understanding of the physics process in the thruster. In this paper, low-power arcjet thrusters are studied numerically using argon as the propellant. The all-speed SIMPLE algorithm is used for the solution of the governing equations, including temperature- and pressure-dependent gas properties. Computed results are presented concerning the temperature, pressure, axial velocity and Mach number distributions within in the thruster nozzle under typical operating conditions. It is found that the heating of the propellant takes place mainly in the constrictor. Under typical operating conditions studied here, the computed specific impulses and mass flow rates of the argon arcjet thruster are roughly consistent with corresponding experimental data. The effects of the geometrical sizes of the arcjet are also investigated.

Radiometric Analysis from the 26-kW Electric Propulsion Space Experiment (ESEX) Flight

Abstract: : The United States Air Force Research Laboratory's Electric Propulsion Space Experiment (ESEX) was launched and operated in early 1999 in order to demonstrate the compatibility and readiness of a 30 kW class ammonia arcjet for satellite propulsion applications. As part of this flight, an array of on-board contamination sensors was used to assess the effect of the arcjet and other environments on the spacecraft. The sensors consisted of microbalances to measure material deposition, radiometers to assess material degradation due to thermal radiation, and solar cell segments to investigate solar array degradation. Over eight firings of the ESEX arcjet, (3 minutes, 26 seconds operating time) the radiometer near the thruster, viewing the arcjet plume and body, experienced a change in the thermal properties of its coating (repetitive) Radiometers with no view of the arcjet, or a view of only the plume, show no change. In general, contamination effects are observed only on sensors near the thruster exhaust nozzle, a location unlikely to be used in an operational high-power electric propulsion system. No contamination effects are observed in the backplane of the thruster. For future programs, while engineering measures may be needed for spacecraft equipment in the immediate vicinity of the thruster body, the arcjet environment is generally benign.