Analysis of Energy Utilization and Losses for Jet-Propelled Vehicles

The global control volume-based energy utilization balance for an aerospace vehicle is extended to allow for the analysis of jet-propelled vehicles. The methodology is first developed for analyzing the energy utilization and entropy generation characteristics of jet engines without airframe considerations. This methodology, when combined with separate energy utilization analysis for an unpowered airframe, allows for the assessment of a powered vehicle. Wake entropy generation for a powered vehicle is shown to be the summation of the wake entropy generation associated with the propulsion system (no airframe) and the unpowered airframe. The fundamental relationship between overall entropy generation and the flight conditions required for maximum range and endurance of a powered vehicle are also derived. Example energy utilization results obtained for a modeled turbojet engine in off-design operation are provided; wake and engine component entropy generation characteristics are directly related to engine operation and flight conditions. This engine model is then integrated with a legacy (twin-engine) Northrop F-5E Tiger II airframe. The overall entropy generation temporal rate for the vehicle is minimized, as predicted by our analysis, at flight conditions corresponding to maximum endurance. For flight conditions corresponding to maximum range, the overall entropy spatial rate is minimized.

Heat Treatment Design of Martensitic Alloys for Engine Valvetrain Component Application - Phase Transformation and Temper Response

Phase transformation and temper response of three martensitic alloys were investigated as an important portion of fundamental metallurgical information database related to heat treatment design for engine component applications. A limited metallographic evaluation has also been carried out with selected temper response run samples in this study. Basic descriptions on adequate hardening and tempering parameter design were provided in terms of optimizing the intended performance with these alloys.

Design And Build Of Gabah Processing Machine 5 Kg Capacity Transmission System

Grain processing machinesis a machine designed to improve map welfareni in the district area Nganjuk. This engine component containsri of the paring system,separator system,transmission systemand order. The transmission part serves totransmits the rotation of the drive motor to the driven mechanism through the pully and v-belt. This machine has a capacity of 5 kg at a time.The discussion focused on the transmission system and frame. Main powerin the form of an electric motorto be transmittedusing pulleys and V-belt. Using motor 0.75HP with a motor rotation of 1400 rpm on the main motor. Transmi typesi used pulleys and belts-v, with belt type A. The drive pulley on the motor is 75mm,puli on a 75mm grinder.

Study on Component Characteristic Correction Algorithm of Turbofan Engine

The optimization of component characteristics is an important part of the research on model modification of turbofan engine. This paper studied three kinds of modification and optimization algorithms: genetic algorithm (GA), differential evolution algorithm (DE) and particle swarm optimization algorithm (PSO), and made a comparative analysis on the principles of the algorithms. In addition, the DGEN380 turbofan engine component model was taken as the research object to test and compare the modification performance of each algorithm. The results show that：compared with GA, DE algorithm and PSO algorithm have higher adaptability to multi-objective and multi-parameter correction, the success rate can reach 100%, the error is kept within 1%, and the convergence ability is strong. Compared with the other two algorithms, the solving speed of PSO algorithm is more influenced by the initial parameters. This conclusion can provide an important reference for selecting and improving the algorithm.

A new method to improve the real-time performance of aero-engine component level model

In order to improve the real-time performance of aero-engine component-level models, an automatic fast positioning interpolation method is proposed. Based on the maximum parameter slope, this method can automatically determine the interpolation cut in point, change the disadvantage of low efficiency of traditional sequential interpolation from the starting point, effectively reduce the interpolation interval, thus greatly improving the efficiency of interpolation. The method is applied to the calculation of gas thermodynamic parameters and the interpolation of the characteristic of rotating parts ,so as to ameliorate the real-time performance of the single-stage flow path calculation of the component-level model. Simulation results show that, compared with the traditional method, the method proposed in this paper improves the fan characteristic calculation efficiency by 47.5%, reduces the time of single complete flow calculation by 74.3% when the dynamic and steady-state accuracy changes are less than 0.4%, which greatly improves the real-time performance of the component-level model.

Preliminary Research on Future Smart Engine Architecture

Aero engines that fit the future have now increasingly attracted the attention of aerospace industry and academia. With this trend, many research projects have been carried out to explore future aero engine technologies. This paper focuses on engine design field, and aims to satisfy the future flight missions that may be unpredictably varying. However, the intrinsic strong coupling of engine component matching mechanism blocks acceleration of engine design. Under this condition, this paper comes up with the concept of smart engine architecture that via a series of engine decoupling strategies, the components can be decoupled to an extent that by properly selecting and assembling them, an engine that satisfies certain flight mission can be designed, this is named mission-oriented pluggable design mode in this paper. Following this idea, a multi-purpose engine design scheme is presented to demonstrate the potential of this engine design mode, and further value of smart engine architecture is discussed.

Experimental Study of Filtration Materials Used in the Car Air Intake

Traditional cellulose filter media used for air filtration in vehicle engines are characterized by 99.9% filtration efficiency and accuracy above 2–5 µm. The highest engine component wear is caused by dust grains above 1 µm. Filter media with nanofiber additions provide greater filtration efficiency of dust grains below 5 µm. Filter material selection for vehicle engine air filter is a problem because their manufacturers mainly provide only the structure parameters: pore size, air permeability, and thickness. There is no information about material filtration properties using polydisperse test dust. The manuscript presents methodology and experimental test results of five samples A, B, C, D and E, filter materials differing in their chemical composition and structure parameters. In the first stage, efficiency characteristics φw, filtration accuracy dzmax and the flow resistance Δpw depending on the dust absorption coefficient km of three filter cartridges of each material, A, B, C, D and E, were determined. Then, from each material characteristics of one piece was selected in order to compare their initial and initial period efficiencies as well as changes in the flow resistance depending on the dust absorption coefficient km. Obtained results showed that the filter materials differ significantly in efficiency and accuracy values in the initial filtration period. Initial period duration is also different, i.e., filtration efficiency increasing time to a certain value, which for materials with a nanofiber layer is much shorter, which minimizes engine component wear. For materials with nanofibers, flow resistance increase intensity is greater, which results from surface filtration. Filtration efficiency of each filter material sample A, B, C, D and E was assessed with the filtration quality coefficient including the efficiency and flow resistance. In the available literature, the problem of increasing filtration efficiency in the initial period is known, but there are no results for specific filter materials. Research shows that filter material characteristics are closely related. Each increase in efficiency and accuracy of intake air filtration reduces engine components wear, but it is related to flow resistance increase in the engine intake system, which reduces its power, and increases need for more frequent filter servicing.