A Review of Commuter Propulsion Technology

Turboprop Cycle Optimization Using Repulsive Particle Swarm Algorithm

“…[3][4][5] show that the process converges in few iterations (about 30-40). Preliminary peaks are due to the chaotic perturbation in position as well as velocity of some particles imposed to make the exploration more efficient and avoid caught in local optimum.…”

“…When considering the design of a turboprop for an appropriate flight mission, the objective is to determine the optimum cycle parameters in terms of turbine inlet temperature (TIT), overall pressure ratio (OPR) and separate pressure ratios, and power turbine temperature expansion rate (TTR) corresponding to most of the extracted power with a residual jet thrust (5-10 % [3]), as well as engines' components technology level. Many studies were undertaken by several authors to determine the turboprop's optimum cycle parameters, as an example, the PW100 turboprop [4] designed in cruise at 28,000 ft and 350 mph, has resulted in an OPR of 15 and a TITof 2000 F. Brooks and Hirschkron [5] reviewed advanced turboprops for commuter aircraft and arrived at values of 17 and 2300 F. Hirschkron and Davis [6] carried out a study of advanced turboprops for a long endurance antisubmarine warfare (ASW) aircraft and proposed an OPR of 22 and a TIT of 2400 F for an engine in the 5000-6000 shaft horse power (SHP) class. Previous studies were based on extensive variations of parameters and involved only one objective usually fuel consumption, and did not show any comparison between performance of various turboprop designs under same operating conditions while considering the on-design and the off-design.…”

Optimizations of turboprop engines using the non-dominated sorting genetic algorithm

“…Several studies were performed to determine the optimal propulsion cycle and many of them were basically parametric analyses. Brooks and Hirschkron [3] proposed, for a commuter aircraft, an overall pressure ratio (CPR) of 17 and TIT of 2300 • F. Similarly, Hirschkron and Davis [4] carried out a study of advanced turboprops in the 5000-6000 hp class and reached a CPR of 22 and a TIT of 2400 • F. In fact, the optimization tools become inevitable to explore the whole design space and produce feasible solutions without recourse to extensive parameter variations, as used in the basic parametric studies.…”

“…Several studies were performed to determine the optimal propulsion cycle and many of them were basically parametric analyses. Brooks and Hirschkron [3] proposed, for a commuter aircraft, an overall pressure ratio (CPR) of 17 and TIT of 2300 • F. Similarly, Hirschkron and Davis [4] carried out a study of advanced turboprops in the 5000-6000 hp class and reached a CPR of 22 and a TIT of 2400 • F. In fact, the optimization tools become inevitable to explore the whole design space and produce feasible solutions without recourse to extensive parameter variations, as used in the basic parametric studies.Owing to the facts that maximizing the power, minimizing the fuel consumption, while maintaining the power levels, or maximizing the engine life by reducing the temperature of the power turbine blades, while maintaining the power levels, are important objectives in the turboprop applications, thus it is very important to make trade-offs between all design criteria and constraints. When combining these objectives, which…”

Minimum power requirement for a propeller-driven aircraft and optimum cycle parameters of turboprop engines

“…Morris [2] showed that if size effects are ignored, an overall pressure ratio in excess of 30 and a turbine inlet temperature of 1700 K could be reached. Brooks and Hirschkron [3] suggested cycle parameters CPR (17)(18)(19)(20) and TIT (1535-1590 K) for commuter aircrafts. For an engine of 12 000 SHP, Banach and Reynolds [4] suggested values of 30 and 1500 K for CPR and TIT, respectively.…”