Design of Cascades for Incompressible Plane Potential Flows With Prescribed Velocity Distribution

1971 ◽  
Vol 93 (3) ◽  
pp. 321-331 ◽  
Author(s):  
W. Schwering
Keyword(s):  
Velocity Distribution ◽  
Surface Velocity ◽  
Two Dimensional ◽  
Blade Profile ◽  
Method Of Calculation ◽  
Potential Flows ◽  
Loss Coefficients ◽  
Optimum Velocity ◽  
Made In

A method of calculation in designing two-dimensional cascades with given velocity distribution is described. An iterative method of the solution for the integral equation to determine the coordinate function for the blade profile is presented. A parametric formulation for the surface velocity distribution is developed. Some design examples for deceleration cascades with given flow angles and prescribed velocity distribution are discussed. Calculations of the boundary layers along the surfaces of the airfoil and cascade loss coefficients are made in order to obtain information on the quality of cascades designed by this method. Proceeding from the results of boundary layer calculations, it should be possible to further improve the parametric formulation for the surface velocity distribution and in this way prescribe better or even “optimum” velocity distributions.

Study on Blade Bend Optimization of Aircraft Engine

2012 ◽  
Vol 538-541 ◽  
pp. 516-519
Author(s):  
Wang Sheng Liu ◽  
Chun Lai Hu ◽  
Yan Sun ◽  
Guo Dong Shi ◽  
Xing Long Liu
Keyword(s):  
Velocity Distribution ◽  
Optimization Design ◽  
Aircraft Engine ◽  
Surface Velocity ◽  
Blade Profile ◽  
The Third ◽  
Blade Thickness ◽  
Design Behaviour

Whether blade profile of aircraft engine is reasonable depends on whether the surface pneumatic distribution given is satisfactory[1,2].In the experiments of optimization design,we discover that the design results are too dependent on surface velocity distribution with the following problems:The first is that the blade bend does not meet the requirements;The second is that blade thickness does not meet the requirements;The third is that the profiles of suction and pressure surfaces are not superposed very well at the leading and following edges with mouth open or cross;The fourth is that some situations of non-design behaviour are not taken into account. In this paper,these issues of blade bend optimization are discussed.

Two-Dimensional Compressor Cascades With Optimum Velocity Distribution Over the Blade

1975 ◽  
Vol 97 (1) ◽  
pp. 101-109
Author(s):  
J. Citavy´
Keyword(s):  
Velocity Distribution ◽  
Two Dimensional ◽  
Suction Surface ◽  
Inverse Cascade ◽  
Pressure Distributions ◽  
Boundary Layer Method ◽  
Optimum Velocity ◽  
Stagger Angle ◽  
The Given

Results are presented of a research on an optimum cascade problem in two-dimensional subsonic flow at SVUSS (National Research Institute for Machine Design, Bechovice). The optimisation is based on a determination of the optimum velocity distribution (OVD) and on the solution of the inverse cascade problem. The OVD has been ascertained from a variational problem formulated by Sˇpacˇek as follows: to find such a velocity distribution on the suction surface for which the momentum thickness at the trailing edge has a minimum value. The problem was solved by Ru˚zˇicˇka using a simplified boundary layer method. Inverse cascade problem due to Pola´sˇek was employed to calculate the cascade geometry for a given optimum velocity distribution and the given stagger angle and the space chord ratio. Series of compressor cascades having the optimum velocity distributions has been designed by means of a digital computer. Some cascades of the series were tested in the low-speed windtunnel as well as at the high subsonic speeds. Reasonable agreement between the predicted and the experimental pressure distributions, flow deflection and loss coefficient has been achieved.

Spectrophotometric measurements of objective-prism spectra

1966 ◽  
Vol 24 ◽  
pp. 118-119
Author(s):  
Th. Schmidt-Kaler
Keyword(s):  
Progress Report ◽  
Two Dimensional ◽  
Objective Prism ◽  
Made In

I should like to give you a very condensed progress report on some spectrophotometric measurements of objective-prism spectra made in collaboration with H. Leicher at Bonn. The procedure used is almost completely automatic. The measurements are made with the help of a semi-automatic fully digitized registering microphotometer constructed by Hög-Hamburg. The reductions are carried out with the aid of a number of interconnected programmes written for the computer IBM 7090, beginning with the output of the photometer in the form of punched cards and ending with the printing-out of the final two-dimensional classifications.

PERBANDINGAN METODE HOMOMORPHIC FILTERING DAN METODE CONTRAST STRECHING UNTUK PERBAIKAN KUALITAS CITRA UNDERWATER

2018 ◽  
Vol 2 (1) ◽  
Author(s):  
Adi Mora Lubis ◽  
Nelly Astuti Hasibuan ◽  
Imam Saputra
Keyword(s):  
Digital Image ◽  
Water Environment ◽  
Repair Process ◽  
Image Process ◽  
Two Dimensional ◽  
Two Dimensional Image ◽  
Underwater Image ◽  
Homomorphic Filtering ◽  
Contrast Stretching

Digital imagery is a two-dimensional image process through a digital computer that is used to manipulate and modify images in various ways. Photos are examples of two-dimensional images that can be processed easily. Each photo in the form of a digital image can be processed through a specific software. In the water environment, the light factor greatly influences the results of the quality of the image obtained. With the deepening of underwater shooting, the results obtained will be the darker the quality of the underwater image. . uneven lighting and bluish tones. One of the factors that influence the recognition results in pattern recognition is the quality of the image that is inputted. The image acquired from the source does not always have good quality. The process of repairing digital images that experience interference in lighting. The lighting repair process uses homomorphic filtering and uses contrast striching and will compare the quality of both methods and test to prove the results of image quality between homomorphic filtering and contrast streching. Until later the results of both methods can be seen which is better. homomorphic filtering and contrast stretching can produce image improvements with pretty good performance.Keywords: Digital Image, Underwater Image, Homomorphic Filtering, Contrast Streching, Matlab R2010a

IMPLEMENTASI METODE RETINEX UNTUK MENINGKATKAN KUALITAS CITRA UNDERWATER

2018 ◽  
Vol 2 (1) ◽  
Author(s):  
Bainun Harahap
Keyword(s):  
Water Environment ◽  
Repair Process ◽  
Image Process ◽  
Two Dimensional ◽  
Two Dimensional Image ◽  
Underwater Image ◽  
Object Search ◽  
Image Improvement ◽  
Underwater Object

Digital imagery is a two-dimensional image process through a digital computer that is used to manipulate and modify images in various ways. Photos are examples of two-dimensional images that can be processed easily. Each photo in the form of a digital image can be processed through certain software devices. In the water environment, light factors greatly influence the results of image quality obtained. With the deepening of underwater shooting, the results obtained will be the darker the quality of the underwater image. Underwater imagery is widely used as an object in various activities such as underwater habitat mapping, underwater environment monitoring, underwater object search. Uneven lighting and colors that tend to be bluish and runny. One of the factors that influence the recognition results in pattern recognition is the quality of the image that is inputted. The image acquired from the source does not always have good quality. The process of improvement in digital images that experience interference in lighting and exposure to sunlight. The lighting repair process uses the retinex method and will compare the quality of the two methods later. Until later the results of both methods can be seen which is better. Retinex method can produce image improvement with high performance.Keywords: Digital Cintra, Underwater, Matlab Retinex Method

Reuse of Sludge from Pulp and Paper Industry Pilot and Full Scale Applications

1993 ◽  
Vol 28 (2) ◽  
pp. 17-26 ◽  
Author(s):  
V. Eroǧlu ◽  
A. M. Saatçi
Keyword(s):  
Economic Analysis ◽  
Paper Industry ◽  
Pulp And Paper Industry ◽  
Pulp And Paper ◽  
Full Scale ◽  
Primary Sludge ◽  
Recent Advances ◽  
Made In

Recent advances made in the reuse of pulp and paper industry sludges in hardboard production are explained. Data obtained from pilot and full-scale plants using primary sludge of a pulp and paper industry as an additive in the production of hardboard is presented. An economic analysis of the reuse of pulp and paper primary sludge in hardboard manufacturing is given. The quality of the hardboard produced is tested and compared with the qualities of the hardboard produced by the same plant before the addition of primary sludge. The hardboard with primary sludge additive has been used in Turkey for about a year in the manufacturing of office and home furniture. The results are very satisfactory when the primary sludge is used at 1/4 ratio.

scholarly journals Two-Dimensional Sampling-Recovery Algorithm of a Realization of Gaussian Processes on the Input and Output of Linear Systems

Entropy ◽  
2020 ◽  
Vol 22 (10) ◽  
pp. 1079
Author(s):  
Vladimir Kazakov ◽  
Mauro A. Enciso ◽  
Francisco Mendoza
Keyword(s):  
Gaussian Processes ◽  
Research Method ◽  
General Algorithm ◽  
Two Dimensional ◽  
Recovery Algorithm ◽  
Conditional Mean ◽  
Quality Of Recovery ◽  
Input And Output ◽  
Statistical Relationships

Based on the application of the conditional mean rule, a sampling-recovery algorithm is studied for a Gaussian two-dimensional process. The components of such a process are the input and output processes of an arbitrary linear system, which are characterized by their statistical relationships. Realizations are sampled in both processes, and the number and location of samples in the general case are arbitrary for each component. As a result, general expressions are found that determine the optimal structure of the recovery devices, as well as evaluate the quality of recovery of each component of the two-dimensional process. The main feature of the obtained algorithm is that the realizations of both components or one of them is recovered based on two sets of samples related to the input and output processes. This means that the recovery involves not only its own samples of the restored realization, but also the samples of the realization of another component, statistically related to the first one. This type of general algorithm is characterized by a significantly improved recovery quality, as evidenced by the results of six non-trivial examples with different versions of the algorithms. The research method used and the proposed general algorithm for the reconstruction of multidimensional Gaussian processes have not been discussed in the literature.

Wrist strength limitations to manual exertion capability

1998 ◽  
Vol 1 (2) ◽  
pp. 107-121
Author(s):  
Khaled W. Al-Eisawi ◽  
Carter J. Kerk ◽  
Jerome J. Congleton
Keyword(s):  
Biomechanical Modeling ◽  
Two Dimensional ◽  
Wrist Flexion ◽  
College Age ◽  
Biomechanical Models ◽  
Radial Deviation ◽  
Flexion Strength ◽  
Made In

This study evaluated wrist strength limitations to manual exertion capability in two-dimensional static biomechanical modeling. The researchers hypothesized that wrist strength does not limit manual exertion capability - an assumption commonly made in many strength biomechanical models. An experiment was conducted on 15 right-handed males of college age. Isometric wrist flexion strength was measured at two elbow angles: 90 degree and 135 degree and in two wrist positions: neutral and 45 degree extended. Isometric wrist radial deviation strength was measured at the same two elbow angles and in two wrist positions: neutral and 30 degree ulnarly deviated. Minimum wrist strength limits for which wrist strength does not limit maximal moments about the elbow in manual hand exertions were calculated and compared to their corresponding measured wrist strength moments using paired t-tests. In general, wrist strength was non-limiting. However, wrist flexion strength in the 45 degree extended wrist posture was limiting. Weak-wrist subjects showed more wrist strength limitations than strong-wrist subjects.

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