International Journal of Turbo & Jet-Engines最新文献_第2页

Air tab location effect on supersonic jet mixing 气片位置对超音速喷流混合的影响

International Journal of Turbo & Jet-Engines Pub Date : 2024-04-04 DOI: 10.1515/tjj-2024-0017

Mahendra Perumal Govindan, Aravindh Kumar Suseela Moorthi, S. Elangovan, Munisamy Sundararaj, E. Rathakrishnan

{"title":"Air tab location effect on supersonic jet mixing","authors":"Mahendra Perumal Govindan, Aravindh Kumar Suseela Moorthi, S. Elangovan, Munisamy Sundararaj, E. Rathakrishnan","doi":"10.1515/tjj-2024-0017","DOIUrl":"https://doi.org/10.1515/tjj-2024-0017","url":null,"abstract":"\u0000 Mixing of Mach 2.1 circular, jet issuing from a straight convergent-divergent circular nozzle, in the presence of sonic air tabs at exit and shifted locations along the jet axis was investigated experimentally at nozzle pressure ratios (NPR) 3–6, insteps of 1. Two constant area tubes of 1 mm diameter positioned diametrically opposite, at 0 D, 0.25 D, 0.5 D and 0.75 D (where D is the nozzle exit diameter), were used for fluidic injection. The injection pressure ratio (IPR) of air tabs was maintained at 6. The Mach 2.1 jet operated at nozzle pressure ratio (NPR) in the range of overexpanded states corresponding to NPR 3–6 was controlled with the sonic air tabs operating at the underexpanded state corresponding to IPR 6. The impact of air tabs on jet mixing was studied from the measured Pitot pressure along the jet centerline. The centerline pressure decay of the jet confirms that the air tab promotes jet mixing with the entrained air mass, and the mixing promotion caused by the air tab is dependent on tab location as well as the NPR. In the presence of air tabs, the jet possesses shorter core and experiences faster decay than the uncontrolled jet. Also, the air tabs were effective in reducing the number of shock cells and rendering the waves weaker in the jet core. Among the tab locations, the mixing promoting effectiveness of air tabs at 0 D is better than the tabs at shifted locations. The jet core length reduction caused by the air tab at 0 D increases from 25.4 % to 77.2 %, with increasing NPR from 3 to 6. The same trend was noticed for tab location 0.75 D, but not for 0.25 D and 0.5 D locations. The core length reduction for 0.75 D tab location is about 61.4 %, at NPR 6, and 62.1 % and 55.8 %, for NPR 5 and 4 for tab locations 0.25 D and 0.5 D, respectively. Shadowgraph images of the waves present in the jet core confirms the findings of centerline pressure decay results.","PeriodicalId":517068,"journal":{"name":"International Journal of Turbo & Jet-Engines","volume":"94 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140742416","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The overall film cooling performance of crescent holes 新月形孔的整体薄膜冷却性能

International Journal of Turbo & Jet-Engines Pub Date : 2024-03-26 DOI: 10.1515/tjj-2024-0008

Qiuyin Wang, Xiaozhi Duan, Chao Zhou

引用次数: 0

Research on cascade control method for turboshaft engine with variable rotor speed 转子转速可变的涡轮轴发动机级联控制方法研究

International Journal of Turbo & Jet-Engines Pub Date : 2024-03-20 DOI: 10.1515/tjj-2024-0004

WenRong Yao, Wenbo Li, JinDong Wu, Chong Su

{"title":"Research on cascade control method for turboshaft engine with variable rotor speed","authors":"WenRong Yao, Wenbo Li, JinDong Wu, Chong Su","doi":"10.1515/tjj-2024-0004","DOIUrl":"https://doi.org/10.1515/tjj-2024-0004","url":null,"abstract":"\u0000 In order to realize high-quality control for turboshaft engine with variable rotor speed, a cascade control method based on the acceleration estimator of gas turbine speed (N\u0000 \u0000 gdot\u0000 ) through Complementary filtering – incremental nonlinear dynamic inversion (CF-INDI)with Newton’s prediction is proposed. Firstly, an adaptive torsional suppression method based on the Recursive Least Square (RLS) algorithm and combined with the control index of power turbine speed is proposed and designed to solve the torsional instability of control system in turboshaft engine with variable rotor speed. Then, an online N\u0000 \u0000 gdot\u0000 estimated method based on CF-INDI with Newton’s prediction is developed, and the complementary filtering method is applied to compensate for the inaccuracy of the state variable model available at a single working point, and Newton prediction is used to alleviate the problem of lagging acceleration estimate, which is accessible to realize the cascade control for turboshaft engine based on N\u0000 \u0000 gdot\u0000 . The simulation results show that the RLS adaptive torsional filter can effectively suppress the low-order torsional components with frequencies of 1.2 Hz and 2.0 Hz mixing in power turbine speed, and the torsional suppression effect is remarkable. In addition, under different flight conditions, CF-INDI with Newton prediction is faster and more accurate than INDI N\u0000 \u0000 gdot\u0000 estimate, and smoother than central difference method, which proves the feasibility of INDI N\u0000 \u0000 gdot\u0000 estimator. Meanwhile, after the application of CF-INDI with Newton prediction N\u0000 \u0000 gdot\u0000 estimator in cascade control, the anti-interference capacity of power turbine speed is stronger, and the dynamic control effect is superior, which has satisfactory robustness performance.","PeriodicalId":517068,"journal":{"name":"International Journal of Turbo & Jet-Engines","volume":"8 5","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140226452","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Investigation on effect of injector orifice diameter on injector atomization and combustion characteristics of pulse detonation combustor 喷射器孔径对脉冲爆燃燃烧器喷射器雾化和燃烧特性影响的研究

International Journal of Turbo & Jet-Engines Pub Date : 2024-03-11 DOI: 10.1515/tjj-2023-0088

Dingding Wang, Longxi Zheng, Lu Jie, Wenhao Tan, Li Qing

引用次数: 0

Improving thermal performance of turbine blade with combination of circular and oblong fins in a wedge channel: a numerical investigation 在楔形通道中结合圆形和长方形翅片提高涡轮叶片的热性能：数值研究

International Journal of Turbo & Jet-Engines Pub Date : 2024-03-06 DOI: 10.1515/tjj-2024-0010

Goveraiahgari Venkatesh, Reddygari Meenakshi Reddy, Pabbisetty Mallikarjuna Rao

{"title":"Improving thermal performance of turbine blade with combination of circular and oblong fins in a wedge channel: a numerical investigation","authors":"Goveraiahgari Venkatesh, Reddygari Meenakshi Reddy, Pabbisetty Mallikarjuna Rao","doi":"10.1515/tjj-2024-0010","DOIUrl":"https://doi.org/10.1515/tjj-2024-0010","url":null,"abstract":"\u0000 Because of its narrow and aerodynamic design, cooling the trailing edge of a turbine blade offers an essential problem. For the trailing edge internal cooling of gas turbine blades, wedge-shaped channels are used. Pin-fin arrays play a critical role in enhancing heat transmission at the trailing edge of turbine blades. The flow and heat transfer properties of a number of wedge channels with staggered pin-fins of varied shapes are used to develop a design with a more effective heat transfer effect and reduced flow resistance. The present study compares the combination of circular pin fins and oblong pin fins in a wedge duct with a Reynolds number range of 12,000–85,000 and a constant heat flux (surface) of 3280 W/m2 applied to the bottom wall, top wall, and surfaces of the fins. The results indicate that the pressure loss is less in circular fins at the centre and oblong fins side by side, and it is 23.67 % less than circular and oblong fins in opposite positions. The Heat transfer coefficient for circular and oblong fins in opposite positions is 16.72 % higher than circular fins at centre and oblong fin side by side. The thermal performance factor is almost the same for both cases.","PeriodicalId":517068,"journal":{"name":"International Journal of Turbo & Jet-Engines","volume":"33 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140262652","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Numerical investigation of force over the horizontal jet tab of various sector angle fixed to the convergent-divergent nozzle exit 对固定在汇聚-发散喷嘴出口的不同扇形角水平射流片上的力进行数值研究

International Journal of Turbo & Jet-Engines Pub Date : 2024-02-29 DOI: 10.1515/tjj-2023-0107

Asad R. Ahmed, Manikandan Subramaniyan, Sarann Venkataraman, Sri Venkateshwaran Thamizhselvan

引用次数: 0

Influence of metal magnesium addition on detonation initiation in shock wave focusing Pulse Detonation Engine 金属镁添加量对冲击波聚焦脉冲起爆发动机起爆的影响

International Journal of Turbo & Jet-Engines Pub Date : 2024-02-28 DOI: 10.1515/tjj-2023-0070

Yun-Kai Wu, Yun-Tian Zhang, Peng Du, Xi-Wei Cao, Rui Xue

{"title":"Influence of metal magnesium addition on detonation initiation in shock wave focusing Pulse Detonation Engine","authors":"Yun-Kai Wu, Yun-Tian Zhang, Peng Du, Xi-Wei Cao, Rui Xue","doi":"10.1515/tjj-2023-0070","DOIUrl":"https://doi.org/10.1515/tjj-2023-0070","url":null,"abstract":"\u0000 The process of shock wave focusing can make the strength of shock waves be continuously accumulated and turned into detonation wave in Pulse Detonation Engine (PDE). However, its effective application needs the inlet jets be in high temperature and velocity, which is difficult to be satisfied under certain conditions. Therefore, in this paper, metal magnesium assisted detonation initiation is proposed and the effect of magnesium particle addition on the shock wave focusing process in a kerosene-fueled PDE with cavity configuration is investigated through numerical simulation. The result showed that when the temperature of the premixed fuel/air jets injected in opposite direction was set as 650 K, the collision of leading shock waves on the central axis was the main source of energy deposition and the shock wave focusing could make the detonation be initiated in the cavity. When the temperature of jets is reduced to 550 K, fuel ignition and detonation could not be achieved through shock wave focusing. Then adding metal magnesium particles into the combustor made the energy deposition be enhanced and the detonation be induced. The diffusion of metal particles can significantly change the structure, motion, merging and dissipation of vortices in the flow field. Generally, the shock wave focusing process is basically not affected with metal particles injection. Therefore, this method can be successfully employed for detonation initiation in the cavity when the fuel/air premixed jet temperature is not high for PDE.","PeriodicalId":517068,"journal":{"name":"International Journal of Turbo & Jet-Engines","volume":"174 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140422099","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Numerical study on aerodynamic performance of an intake duct affected by ground effect 受地面效应影响的进气管气动性能数值研究

International Journal of Turbo & Jet-Engines Pub Date : 2024-02-22 DOI: 10.1515/tjj-2022-0056

Yalin Shi, Lingling Chen, Pengfei Chen, Qingzhen Yang, Y. Shi, Hua Yang

引用次数: 0

Finite element based dynamic analysis of a porous exponentially graded shaft system subjected to thermal gradients 基于有限元的受热梯度影响的多孔指数分级轴系统动态分析

International Journal of Turbo & Jet-Engines Pub Date : 2024-02-16 DOI: 10.1515/tjj-2023-0103

Vijayakumar Vaka, P. Sathujoda, N. Bhalla, Satishkumar V. Yelike

{"title":"Finite element based dynamic analysis of a porous exponentially graded shaft system subjected to thermal gradients","authors":"Vijayakumar Vaka, P. Sathujoda, N. Bhalla, Satishkumar V. Yelike","doi":"10.1515/tjj-2023-0103","DOIUrl":"https://doi.org/10.1515/tjj-2023-0103","url":null,"abstract":"\u0000 In modern applications, demand for the rotor shafts made of FGM has increased in aerospace, gas turbine and turbo jet engines due to its improved dynamic characteristics at elevated temperatures. The dynamic vibration response of a functionally graded Jeffcott rotor-bearing system with induced porosities has been studied for non-uniform porosity distributions. The functionally graded (FG) shaft’s radial direction exhibits continuous variation in the material qualities. The FG rotor’s cross-sectional material properties have been graded using the exponential law. The temperature gradients have been considered to be varied across the cross-section based on exponential temperature distribution. For the first time, using the FE method, it has been possible to study the impact of induced porosities on the free vibration frequencies and steady-state vibration responses of the functionally graded rotor-bearing system. This has led to the development of a two-node porous functionally graded rotor element with uneven porosity distributions using the Timoshenko beam theory. It has been observed that the free vibration frequencies and the FG rotor-bearing system critical speeds are affected by increased porosity and thermal gradients. The frequency responses demonstrate that as temperature gradient and volume fraction of porosity rise, the FG rotor-bearing system’s critical speeds shift to the left.","PeriodicalId":517068,"journal":{"name":"International Journal of Turbo & Jet-Engines","volume":"321 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139894225","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Numerical investigation on mixing of heated confined swirling coaxial jets with blockage 带阻塞的受热密闭漩涡同轴射流的混合数值研究

International Journal of Turbo & Jet-Engines Pub Date : 2024-02-16 DOI: 10.1515/tjj-2023-0100

Ritesh Srivastava, Vivek Kumar Patel

引用次数: 0

International Journal of Turbo &amp; Jet-Engines最新文献

International Journal of Turbo & Jet-Engines最新文献