Engineering topics

Sanjay Garg

Publications and source records attributed to Sanjay Garg.

4 records

NASA NTRS2009

More Intelligent Gas Turbine Engines

Increased emphasis on aircraft safety, enhanced performance and affordability, and the need to reduce the environmental impact of aircrafts are being addressed through the concept of Intelligent Propulsion Systems. These systems are potentially enabled through increased efficiencies of components through active control, advanced diagnostics and prognostics integrated with intelligent engine control, and distributed control with smart sensors and actuators. The focus of this report is on "On-Board Intelligence", and the discussions are limited to the overall engine gas-path performance perspective. The emphasis throughout the report is on identifying the sensor and actuator needs to realize these intelligent engine concepts and identifying the current sensor and actuator technologies and roadmaps for emerging technologies. The report is of interest both to the "Customers" to understand the investment needs and the "Researchers" and "Technology Developers" to understand the technology needs for closing the gap from current sensor and actuator capabilities to future performance and universal requirements and targets.

active control↗

NASA NTRS2009

Universal Sensor and Actuator Requirements

The previous chapters have focused on the requirements for sensors and actuators for "More Intelligent Gas Turbine Engines" from the perspective of performance and operating environment. Even if a technology is available, which meets these performance requirements, there are still various hurdles to be overcome for the technology to transition into a real engine. Such requirements relate to TRL (Technology Readiness Level), durability, reliability, volume, weight, cost, etc. This chapter provides an overview of such universal requirements which any sensor or actuator technology will have to meet before it can be implemented on a product. The objective here is to help educate the researchers or technology developers on the extensive process that the technology has to go through beyond just meeting performance requirements. The hope is that such knowledge will help the technology developers as well as decision makers to prevent wasteful investment in developing solutions to performance requirements, which have no potential to meet the "universal" requirements. These "universal" requirements can be divided into 2 broad areas: 1) Technology value proposition; and 2) Technology maturation. These requirements are briefly discussed in the following.

Taylor Rosenfeld↗

NASA NTRS2009

Distributed Control Architecture for Gas Turbine Engine

The transformation of engine control systems from centralized to distributed architecture is both necessary and enabling for future aeropropulsion applications. The continued growth of adaptive control applications and the trend to smaller, light weight cores is a counter influence on the weight and volume of control system hardware. A distributed engine control system using high temperature electronics and open systems communications will reverse the growing trend of control system weight ratio to total engine weight and also be a major factor in decreasing overall cost of ownership for aeropropulsion systems. The implementation of distributed engine control is not without significant challenges. There are the needs for high temperature electronics, development of simple, robust communications, and power supply for the on-board electronics.

Dennis Culley↗

NASA NTRS2009

Intelligent Control and Health Monitoring

Advanced model-based control architecture overcomes the limitations state-of-the-art engine control and provides the potential of virtual sensors, for example for thrust and stall margin. "Tracking filters" are used to adapt the control parameters to actual conditions and to individual engines. For health monitoring standalone monitoring units will be used for on-board analysis to determine the general engine health and detect and isolate sudden faults. Adaptive models open up the possibility of adapting the control logic to maintain desired performance in the presence of engine degradation or to accommodate any faults. Improved and new sensors are required to allow sensing at stations within the engine gas path that are currently not instrumented due in part to the harsh conditions including high operating temperatures and to allow additional monitoring of vibration, mass flows and energy properties, exhaust gas composition, and gas path debris. The environmental and performance requirements for these sensors are summarized.

Sanjay Garg↗