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.

Numerical Prediction of the Influence of Process Parameters on Large Area Diamond Deposition by DC Arcjet with ARC Roots Rotating and Operating at Gas Recycling Mode

Abstract: A computer model have been set up for simulation of the flow and temperature field, and the radial distribution of atomic hydrogen and active carbonaceous species over a large area substrate surface for a new type dc arc plasma torch with rotating arc roots and operating at gas recycling mode A gas recycling radio of 90% was assumed. In numerical calculation of plasma chemistry, the Thermal-Calc program and a powerful thermodynamic database were employed. Numerical calculations to the computer model were performed using boundary conditions close to the experimental setup for large area diamond films deposition. The results showed that the flow and temperature field over substrate surface of Φ60-100mm were smooth and uniform. Calculations were also made with plasma of the same geometry but no arc roots rotation. It was clearly demonstrated that the design of rotating arc roots was advantageous for high quality uniform deposition of large area diamond films. Theoretical predictions on growth rate and film quality as well as their radial uniformity, and the influence of process parameters on large area diamond deposition were discussed in detail based on the spatial distribution of atomic hydrogen and the carbonaceous species in the plasma over the substrate surface obtained from thermodynamic calculations of plasma chemistry, and were compared with experimental observations.

Nondestructive evaluation tools and experimental studies for monitoring the health of space propulsion systems

Abstract: An overview is given of background and information on space propulsion systems on both the programmatic and technical levels. Feasibility experimental studies indicate that nondestructive evaluation tools such as ultrasonic, eddy current and x-ray may be successfully used to monitor the life limiting failure mechanisms of space propulsion systems. Encouraging results were obtained for monitoring the life limiting failure mechanisms for three space propulsion systems; the degradation of tungsten arcjet and magnetoplasmadynamic electrodes; presence and thickness of spallable electrically conducting molybdenum films in ion thrusters; and the degradation of the catalyst in hydrazine thrusters.

Comparative Ablation Testing of Carbon Phenolic TPS Materials in the AEDC-H1 Arcjet *

Abstract: Candidate heat shield materials for hypersonic and reentry applications must be ground tested under severe heating and shear conditions representative of flight in order to validate thermal-structural performance prior to flight testing. Arc heaters have found widespread usage in the development of materials for hypersonic missiles, reentry vehicles, high-speed transports, military/civil space transportation and space access vehicles, and ordnance and munitions systems. The High-Enthalpy Ablation Test (HEAT) H1 and H3 arcjet facilities at Arnold Engineering Development Center (AEDC) fill a unique niche in providing high-pressure, high-enthalpy ground test simulations, and they have been widely utilized to test candidate thermal protection system (TPS) materials that are of interest for many hypersonic and reentry systems. H1 and H3 provide high-enthalpy test conditions simulating aeroheating environments consistent with endoatmospheric flight at velocities from 5,000 ft/s up to and exceeding 20,000 ft/s. The combination of high-enthalpy test gas and high plenum pressure makes possible heat flux simulations representing high Mach number flight at high dynamic pressures. The paper includes a description of the H1 test facility, the supporting facility systems, and the TPS material test procedure. A summary of the optical and instrumentation systems used to acquire heat shield ablation performance data for materials in a typical AEDC reentry ground test simulation is also presented.

Primary propulsion of electrothermal, ion and chemical systems for space-based radar orbit transfer

Abstract: An orbit transfer mission concept has been studied for a Space-Based Radar (SBR) where 40 kW required for radar operation is assumed available for orbit transfer propulsion. Arcjet, pulsed electrothermal (PET), ion, and storable chemical systems are considered for the primary propulsion. Transferring two SBR per shuttle flight to 1112 km/60 deg using electrical propulsion systems offers an increased payload at the expense of increased trip time, up to 2000 kg each, which may be critical for survivability. Trade offs between payload mass, transfer time, launch site, inclination, and height of parking orbits are presented.