Large liquid rocket engine transient performance simulation system

A simulation system, ROCETS, was designed and developed to allow cost-effective computer predictions of liquid rocket engine transient performance. The system allows a user to generate a simulation of any rocket engine configuration using component modules stored in a library through high-level input commands. The system library currently contains 24 component modules, 57 sub-modules and maps, and 33 system routines and utilities. FORTRAN models from other sources can be operated in the system upon inclusion of interface information on comment cards. Operation of the simulation is simplified for the user by run, execution, and output processors. The simulation system makes available steady-state trim balance, transient operation, and linear partial generation. The system utilizes a modern equation solver for efficient operation of the simulations. Transient integration methods include integral and differential forms for the trapezoidal, first order Gear, and second order Gear corrector equations. A detailed technology test bed engine (TTBE) model was generated to be used as the acceptance test of the simulation system. The general level of model detail was that reflected in the Space Shuttle Main Engine DTM. The model successfully obtained steady-state balance in main stage operation and simulated throttle transients, including engine starts and shutdown. A NASA FORTRAN control model was obtained, ROCETS interface installed in comment cards, and operated with the TTBE model in closed-loop transient mode

Large liquid rocket engine transient performance simulation system

Phase 1 of the Rocket Engine Transient Simulation (ROCETS) program consists of seven technical tasks: architecture; system requirements; component and submodel requirements; submodel implementation; component implementation; submodel testing and verification; and subsystem testing and verification. These tasks were completed. Phase 2 of ROCETS consists of two technical tasks: Technology Test Bed Engine (TTBE) model data generation; and system testing verification. During this period specific coding of the system processors was begun and the engineering representations of Phase 1 were expanded to produce a simple model of the TTBE. As the code was completed, some minor modifications to the system architecture centering on the global variable common, GLOBVAR, were necessary to increase processor efficiency. The engineering modules completed during Phase 2 are listed: INJTOO - main injector; MCHBOO - main chamber; NOZLOO - nozzle thrust calculations; PBRNOO - preburner; PIPE02 - compressible flow without inertia; PUMPOO - polytropic pump; ROTROO - rotor torque balance/speed derivative; and TURBOO - turbine. Detailed documentation of these modules is in the Appendix. In addition to the engineering modules, several submodules were also completed. These submodules include combustion properties, component performance characteristics (maps), and specific utilities. Specific coding was begun on the system configuration processor. All functions necessary for multiple module operation were completed but the SOLVER implementation is still under development. This system, the Verification Checkout Facility (VCF) allows interactive comparison of module results to store data as well as provides an intermediate checkout of the processor code. After validation using the VCF, the engineering modules and submodules were used to build a simple TTBE

Family Trusts - Time for Reconsideration

The protective legislation which frequently resulted in assets held within a family trust being removed from the ambit of a matrimonial property claim needed legislative amendment and judicial reconsideration in order to prevent potential inequity of division. This article explores the problems and anomalies in the family trusts regime in the 1990s: the Matrimonial Property Act 1976, the Trustee Act 1956, and s 182 of the Family Proceedings Act 1980. The author concludes that the question of whether there is truly equity after separation might not be able to be avoided in an increasingly sophisticated financial society

The Risk of the Female Athlete Triad in Collegiate Athletes and Non-Athletes

Prior research has found the female athlete triad in both female athletes and female non-athletes. This study consisted of 192 female participants attending Utah State University with 103 collegiate athletes and 89 non-athletes. The instruments used included the EAT-26, menstrual cycle history questionnaire, osteoporosis questionnaire, and time spent in exercise questionnaire. Results from the present study found a statistically significant difference between athletes and non-athletes being at risk for the triad with female athletes having a higher percentage (4.8%, 3.4%). No statistical significant correlation was found between the risk of the triad and excessive amounts of time spent in exercise in athletes (r=.113, p=.256) and non-athletes (r=-.041, p=.706). When athletes were divided into lean and non-lean athletes statistical significance was found with non-lean (17.4%) sport athletes (χ²(1,N=103)=83.971, p\u3c.01) having a higher overall percentage of being at risk of the triad compared to the athletes involved in lean (5%) sports