A model for prediction of STOVL ejector dynamics
A semi-empirical control-volume approach to ejector modeling for transient performance prediction is presented. This new approach is motivated by the need for a predictive real-time ejector sub-system simulation for Short Take-Off Verticle Landing (STOVL) integrated flight and propulsion controls design applications. Emphasis is placed on discussion of the approximate characterization of the mixing process central to thrust augmenting ejector operation. The proposed ejector model suggests transient flow predictions are possible with a model based on steady-flow data. A practical test case is presented to illustrate model calibration.
Large-scale wind tunnel tests of an ejector-lift STOVL aircraft model
The initial results of a test program conducted on an ejector-augmented-lift STOVL aircraft design in the NASA-Ames 40-by-80-Foot Wind Tunnel has established the efficient performance of this full-scale aircraft realization of the propulsion-system configuration. It has also been noted that the generation of larger lift-augmentation ratios in this form than in component tests. In addition, it is found that configurations possessing thrust/weight ratios and wing loadings representative of current practice could, when outfitted with the present propulsion scheme, produce adequate level-flight acceleration through transition from VTOL hover to wingborne flight.
Fault Diagnosis and CAN Bus/Ethernet Redundancy Design of a Monitoring and Control System
The ship monitoring system is used to monitor and control the working status of various equipment on the ship. The navigational safety of the ship is affected directly by the stable working of the monitoring system. In this paper, a ship monitoring system with fault-type judgment function and bus redundancy is designed to improve system reliability and reduce fault checking cost. A redundant Ethernet/CAN bus communication network is constructed in the system, which connects multiple simulation nodes. The simulation node can simulate the faults that may occur during the communication process and feeds back the fault information to the host computer. The host computer will analyze and display the corresponding fault type on the user interface with the feedback information is received. The system reconfigures the network route autonomously when the simulation node has a communication fault. Routing of fault nodes can be switched to redundant routing, and the load balancing of the communication network can be maintained. Through experimental tests, the system can accurately locate faults and achieve fast switching of redundant routes between buses. Hence, the reliability of data transmission is improved.