Aircraft Engine Design, Second Edition

Framework for Predicting Noise–Power–Distance Curves for Novel Aircraft Designs

“…The estimation of engine stream velocities (Appendix B) is based on a number of assumptions according to references [30][31][32]. These assumptions are: a) the gas properties are fixed across the components, b) the flow is one-dimensional c) the power needed to drive the fan and high-pressure (HP) compressor equals the power delivered by the low pressure (LP) and HP turbine respectively, and d) the rotating machinery components are assigned fixed, empirically derived polytropic efficiencies that represent a technology level rather than a certain engine.…”

“…These assumptions are: a) the gas properties are fixed across the components, b) the flow is one-dimensional c) the power needed to drive the fan and high-pressure (HP) compressor equals the power delivered by the low pressure (LP) and HP turbine respectively, and d) the rotating machinery components are assigned fixed, empirically derived polytropic efficiencies that represent a technology level rather than a certain engine. According to [30][31][32], assumptions a) to c) produce insignificant stream velocities error. Regarding the last mentioned assumption, the average variation of jet velocities (that are the parameters sought from the cycle analysis) resulting from altering efficiencies by 10% was found to be less than 3%.…”

“…The total mixed jet temperature T tj,∞ of the equivalent single stream engine at rated thrust is obtained from a turbofan engine cycle thermodynamic analysis [30][31][32]. This is done under the assumption that the core stream jet temperature at rated thrust is equal to the operational limit of the low pressure turbine (LPT) exit temperature, which is publicly available in the EASA TCDS certificates [34].…”

Emission of ions and charged soot particles by aircraft engines

“…To complete the combustion process and consume the unburned fuel, additional secondary air is introduced through a second row of lines holes. Finally dilution air is introduced in the dilution zone in order to carefully control exit temperature radial profiles to ensure acceptable turbine durability and performance (Lefebvre, 1985;Mattingly et al, 1987). In the primary zone the air-fuel ratio is less than unity and the temperature is not high enough to complete the fuel burning.…”

Design Methodology of an Annular Combustor for Micro Gas Turbines

“…Aa : cross-section area of annulus Ac : surface area of casing Aft : cross-section area of liner Aw : surface area of liner A/F : air to fuel ratio dh1 : liner width × 2 dha : annulus width × 2 m : mass flow rate P : total pressure   : fuel LHV (lower heating value) T : temperature 가스터빈 연소기 개발 과정은 용도별, 제조사별 로 차이가 있지만 일반적으로 기본설계(preliminary design), 상세설계(detail design), 성능실험(performance tests)에 의한 검증 및 설계보완의 순서로 이루어진 다 [3][4][5] …”