Pratt and Whitney Aircraft Nuclear J58 Turbojet Engine Performance of 1800F NaK Radiator Derated to 1600F

Purpose This study aims to investigate the aviation, energetic, exergetic, environmental, sustainability and exergoeconomic performances of a micro turbojet engine used in unmanned aerial vehicles at four different modes. Design/methodology/approach The engine data were collected from engine test cell. The engine performance calculations were performed for four different operation modes. Findings According to the results, maximum energy and exergy efficiency were acquired as 19.19% and 18.079% at Mode 4. Total cost rate was calculated as 6.757 $/h at Mode-1, which varied to 10.131 $/h at Mode-4. Exergy cost of engine power was observed as 0.249 $/MJ at Mode-1, which decreased to 0.088 $/MJ at Mode-4 after a careful exergoeconomic analysis. Originality/value The novelty of this work is the capability to serve as a guide for similar systems with a detailed approach in the thermodynamic, thermoeconomic and environmental assessments by prioritizing efficiency, fuel consumption and cost formation. This investigation intends to establish a design of the opportunities and benefits that the thermodynamic approach provides to turbojet engine systems.

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Experimental investigation of infrared signal characteristics in a micro-turbojet engine

The Aeronautical Journal ◽

10.1017/aer.2018.164 ◽

2019 ◽

Vol 123 (1261) ◽

pp. 340-355 ◽

Cited By ~ 1

Author(s):

S. M. Choi ◽

S. Kim ◽

R. S. Myong ◽

W. Kim

Keyword(s):

Temperature Distribution ◽

Aspect Ratio ◽

Fuel Consumption ◽

Engine Performance ◽

Gas Temperature ◽

Fuel Consumption Rate ◽

Aspect Ratios ◽

Turbojet Engine ◽

Signal Characteristics ◽

Cone Type

ABSTRACTInfrared signal measurements from a micro-turbojet engine are conducted to understand the characteristics of the engine performance and the infrared signal by varying the exhaust nozzle configuration. A cone type nozzle and five rectangle type nozzles whose aspect ratios vary from one to five are used for this experimental work. As a result, it is confirmed that the thrust and the fuel consumption rate of the engine do not change greatly by varying the exhaust nozzle shape. In the case of the aspect ratio of 5, the specific fuel consumption of the engine is increased by about 3% compared to the reference cone nozzle, but the infrared signal can be reduced by up to 14%. As a result of measuring the temperature distribution of the plume gas, the correlation of infrared signal with plume gas temperature distribution can be understood. In the case of a cone shape, the distribution of plume gas formed to circular shape, and the high-temperature core region of plume gas continued to develop farther to the downstream. However, the temperature distribution was maintained in the rectangular shape as the aspect ratio increased, and the average temperature decreased sharply. As the aspect ratio increases, the plume spreads more widely.

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ATF Test Evaluation of Model Based Control for a Single Spool Turbojet Engine

Volume 1: Aircraft Engine; Ceramics; Coal, Biomass and Alternative Fuels; Controls, Diagnostics and Instrumentation; Education; Electric Power; Awards and Honors ◽

10.1115/gt2009-59854 ◽

2009 ◽

Cited By ~ 1

Author(s):

Takeshi Tagashira ◽

Takuya Mizuno ◽

Masaharu Koh ◽

Nanahisa Sugiyama

Keyword(s):

Control System ◽

Engine Performance ◽

Good Control ◽

Test Facility ◽

Sensor Failure ◽

Component Level ◽

Feedback Controls ◽

Model Based Control ◽

Model Based ◽

Turbojet Engine

This paper introduces a model based control system for a single spool turbojet engine. It consists of a feedback control (FBC) and a component level model (CLM) enhanced by the Constant Gain Extended Kalman Filter (CGEKF). The control system is implemented on a rugged PC, and verified to run in much faster than real time, which is essential requirement for a model based control. Then, the model based control system developed is applied to an actual engine and evaluation test is conducted by using an Altitude Test Facility (ATF). Several types of model based feedback controls are evaluated under various flight conditions, giving intentional engine performance change by varying nozzle area, and intentional sensor failure. It is concluded that the model based control using CGEKF is stable and shows good control performances over the whole flight envelope.

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