توجه: محتویات این صفحه به صورت خودکار پردازش شده و مقاله‌های نویسندگانی با تشابه اسمی، همگی در بخش یکسان نمایش داده می‌شوند.
۱TIP CLEARANCE FLOW IN A LOW SPEED HIGHLY STAGGERED COMPRESSOR CASCADE
نویسنده(ها): ، ،
اطلاعات انتشار: سیزدهمین کنفرانس سالانه مهندسی مکانیک، سال
تعداد صفحات: ۷
To get a better understanding of the complex flowfield in axial flow compressors, a three–dimensional incompressible solver with κ–ε turbulence model and unstructured grid has been applied to a highly staggered compressor cascade including tip clearance. For a linear compressor cascade with GE rotor B, the flowfield and pressure distributions are studied and compared with available experimental and numerical data. The computations are used to describe the features of tip clearance flow and furthermore, the tip leakage vortex and the endwall region flow characteristics are discussed.<\div>

۲CALCULATION OF TIP CLEARANCE SIZE EFFECTS FOR THE NASA ROTOR 37 COMPRESSOR BLADE
نویسنده(ها): ، ، ،
اطلاعات انتشار: سیزدهمین کنفرانس سالانه مهندسی مکانیک، سال
تعداد صفحات: ۹
Compressors often operate with a tip clearance larger than aerodynamically desired basically due to the changes of tip clearance during operations as well as manufacturing limitations. To assess the effects of tip gap size on the performance of an axial transonic compressor, the through flow in the tip gap region of NASA Rotor 37 compressor blade is numerically studied and compared to aerodynamic probe and laser
anemometer data. The computations show a good agreement. Results discuss how increasing the tip gap size degrades the efficiency, the pressure ratio and the overall performance of axial transonic compressors.<\div>

۳Experimental Investigation of Detonation Wave Initiation for Application in Pulse Detonation Engines
نویسنده(ها): ، ،
اطلاعات انتشار: شانزدهمین کنفرانس سالانه مهندسی مکانیک، سال
تعداد صفحات: ۶
We have designed, manufactured, and tested a detonation tube to investigate detonation wave initiation and propagation for application in a ingletube, single–cycle pulse detonation engine. A key issue in pulse detonation engine development is a low–energy initiation system that produces a short run–up distance to detonation and has reproducible shot–to–shot performance. In this paper, we performed primarily study of detonation initiation within a 25 mm diameter tube using spark ignition and a Shchelkin spiral. A series of experiments have been reported with hydrogen fuel mixed with oxygen .Essential parameters like pressure and velocity were measured. Effect of equivalence ratio, length tube and Shchelkin spiral investigated. Excremental results such as pressure histories, wave velocity versus position, were plotted and discussed. Results show continues increasing detonation velocity with equivalence ratio. We have used specific configuration setup to reduction DDT length.
Experimental results indicate occurrence of detonation in a short distance (~200 mm) from the ignition point.<\div>

۴Modelling of Mean Drop Size in a Extraction Spray Column and Developing a New Model
نویسنده(ها): ، ، ، ، ،
اطلاعات انتشار: Iranian Journal of Chemistry and Chemical Engineering (IJCCE)، سي ام،شماره۴(پياپي ۶۰)، ۲۰۱۱، سال
تعداد صفحات: ۸
Drop size distribution plays a key role in the liquid extraction systems and related hydrodynamic and mass transfer parameters. In current research work, the size of drops in an extraction spray column has been measured by direct photography method, and the Sauter mean diameter has been obtained accordingly. Then, two types of models are assessed based on using dimensionless analysis and appropriate software. The interfacial tension in used chemical system is 1.8–32 dyne\cm. In first type of models, the correlation is established based on dimensionless parameters similar to approaches defined by other researchers. In second types, dimensional parameters have been used and therefore a new model is introduced for multi–drop extraction columns. The results show that the drop size diameter has the most affect on Eötvös number (Eo) in the first type of model and the correlation based on Eo number predicts drop size diameter with 8.1% error. In the second ones, four dimensional parameters (dN, Dr, s, u) have been selected as the most effective variables on drop size diameters and modelling results show prediction of drop size diameters with 5.82% error. In other cases, without using «u» as a variable, the amount of error has been decreased to 5.73% which shows better fitting.
نمایش نتایج ۱ تا ۴ از میان ۴ نتیجه