The MPE toolkit for supporting distributed applications

This paper presents a toolkit for supporting the execution of coarse-grain, parallel (distributed) applications under the MOSIX multicomputer operating system. These tools use standard UNIX System V process control and message-passing facilities, as well as the dynamic process migration mechanisms of MOSIX. The MPE tools can be used to modify sequential applications that were originally written for execution in a uniprocessor environment, to run efficiently in a distributed environment, consisting of several loosely coupled independent computers that communicate by messages. After presenting the MPE tools, the paper gives examples of several sequential algorithms that have been modified for execution in such a distributed multicomputer, as well as the resulting execution speed-ups that were obtained.     

Numerical Solution of the Flow of Power‐Law Gel Propellants in Converging Injectors

The governing equations of the steady, incompressible, isothermal, laminar flow of a power‐law, shear‐thinning gel propellant in a converging injector were formulated. The equations were transformed to a ψ–ω system, then discretized and solved. A numerical algorithm was developed for the solution of the flowfield. A parametric investigation was conducted to evaluate the effect of the injector geometry and the flow rate on the velocity and viscosity fields, for various gel propellants. In comparison to a straight injector, a convergent one can produce additional decrease in the mean apparent viscosity of the fluid. The mean apparent viscosity decreases significantly with increasing the convergence angle of the injector. In general, increasing the gel flow rate results in a decrease of the mean apparent viscosity of the fluid. Increasing the gellant content of gel propellants results in an increase of the fluid viscosity that decreases when the gel flows through the injector. Gels of different gellant content that flow through the same geometry injector exhibit similar relative reduction in viscosity.