Throughflow Theory for Nonaxisymmetric Turbomachinery Flow: Part II—Assessment

R. P. Dring; G. C. Oates

doi:10.1115/1.2927664

Throughflow Theory for Nonaxisymmetric Turbomachinery Flow: Part I—Formulation

Journal of Turbomachinery ◽

10.1115/1.2927661 ◽

1990 ◽

Vol 112 (3) ◽

pp. 320-326 ◽

Cited By ~ 6

Author(s):

R. P. Dring ◽

G. C. Oates

Keyword(s):

Total Pressure ◽

Present Formulation ◽

Dominant Effect ◽

Flow Equations ◽

Blockage Factor ◽

Through Flow ◽

Benchmark Database ◽

Flow Part

Throughflow theory has been limited in its applicability and in its accuracy by the fact that it has not historically been cast in a form that can account for the non-axisymmetries that naturally arise in turbomachinery flow due to the presence of finite numbers of rotor and stator airfoils. The attempt to circumvent this limitation by the introduction of an aerodynamic blockage factor has been demonstrated in earlier work to produce fundamental inconsistencies in the calculation, which lead to significant errors in the regions of the flow where the nonaxisymmetries are severe. The formulation in Part I of the present work is a derivation of a system of through-flow equations for nonaxisymmetric flow. A benchmark database is used in Part II to provide input to the calculation and to help identify the dominant terms. It is demonstrated that the dominant effect of nonaxisymmetry is contained in two terms that relate the total pressure of the averaged flow to the mass-averaged total pressure. It also is demonstrated that the present formulation produces a result that is more accurate than that obtained with the historical blockage-based formulation.

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Through Flow Theory for Nonaxisymmetric Turbomachinery Flow: Part I — Formulation

Volume 1: Turbomachinery ◽

10.1115/89-gt-304 ◽

1989 ◽

Author(s):

Robert P. Dring ◽

Gordon C. Oates

Keyword(s):

Data Base ◽

Total Pressure ◽

Flow Theory ◽

Present Formulation ◽

Dominant Effect ◽

Flow Equations ◽

Benchmark Data ◽

Blockage Factor ◽

Through Flow ◽

Flow Part

Through flow theory has been limited in its applicability and in its accuracy by the fact that it has not historically been cast in a form which can account for the nonaxisymmetries that naturally arise in turbomachinery flow due to the presence of finite numbers of rotor and stator airfoils. The attempt to circumvent this limitation by the introduction of an aerodynamic blockage factor has been demonstrated in earlier work to produce fundamental inconsistencies in the calculation which lead to significant errors in the regions of the flow where the nonaxisymmetries are severe. The formulation in Part I of the present work is a derivation of a system of through flow equations for nonaxisymmetric flow. A benchmark data base is used in Part II to provide input to the calculation and to help identify the dominant terms. It is demonstrated that the dominant effect of nonaxisymmetry is contained in two terms that relate the total pressure of the averaged flow to the mass averaged total pressure. It is also demonstrated that the present formulation produces a result which is more accurate than that obtained with the historical blockage-based formulation.

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Through Flow Theory for Nonaxisymmetric Turbomachinery Flow: Part II — Assessment

Volume 1: Turbomachinery ◽

10.1115/89-gt-305 ◽

1989 ◽

Author(s):

Robert P. Dring ◽

Gordon C. Oates

Keyword(s):

Data Base ◽

Total Pressure ◽

Flow Theory ◽

Present Formulation ◽

Dominant Effect ◽

Flow Equations ◽

Benchmark Data ◽

Blockage Factor ◽

Through Flow ◽

Flow Part

Through flow theory has been limited in its applicability and in its accuracy by the fact that it has not historically been cast in a form which can account for the nonaxisymmetries that naturally arise in turbomachinery flow due to the presence of finite numbers of rotor and stator airfoils. The attempt to circumvent this limitation by the introduction of an aerodynamic blockage factor has been demonstrated in earlier work to produce fundamental inconsistencies in the calculation which lead to significant errors in the regions of the flow where the nonaxisymmetries are severe. The formulation in Part I of the present work is a derivation of a system of through flow equations for nonaxisymmetric flow. A benchmark data base is used in Part II to provide input to the calculation and to help identify the dominant terms. It is demonstrated that the dominant effect of nonaxisymmetry is contained in two terms that relate the total pressure of the averaged flow to the mass averaged total pressure. It is also demonstrated that the present formulation produces a result which is more accurate than that obtained with the historical blockage-based formulation.

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Analisis Pengaruh Kepemimpinan dan Komunikasi Terhadap Motivasi dan Kinerja Pegawai (Satuan Polisi Pamong Praja Kota Surabaya)

Business and Finance Journal ◽

10.33086/bfj.v2i1.467 ◽

2017 ◽

Vol 2 (1) ◽

Author(s):

Muhammad Rodhiyallah ◽

Amiartuti Kusmaningtyas ◽

Hendro Tjahjono

Keyword(s):

Linear Regression ◽

Multiple Linear Regression ◽

Sampling Technique ◽

Employee Motivation ◽

Leadership Communication ◽

Dominant Effect ◽

And Performance

The aim of the study was to analyze and determine the influence of leadership and communication, on employee motivation and performance at Satuan Polisi Pamong Praja Kota Surabaya. Branch, as many as 100 persons. Sampling technique samples (Slovin) data was analyzed with multiple linear regression with SPSS for windows program. The result of the research indicated that leadership, communication, and motivation simultaneously have significant effect on employees’ performances with determination value of 0,424 or 4,24%. Leadership, communication and motivation partially has significant effect on performance. Communication itself has dominant effect on employee’s performance.

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Assessing the Impact of the Inlet Total Pressure Distortion on the Turbofan Thrust

Mechanical Engineering and Computer Science ◽

10.24108/0118.0001360 ◽

2018 ◽

pp. 19-30

Author(s):

Yu. A. Ezrokhi ◽

E. A. Khoreva

Keyword(s):

Total Pressure ◽

External Compression ◽

Average Value ◽

Inlet Distortion ◽

Air Inlet ◽

Engine Thrust ◽

Relative Value ◽

Main Effect ◽

Pressure Recovery Factor ◽

The Impact

The paper considers techniques to develop a mathematical model using a method of «parallel compressors». The model is intended to estimate the impact of the air inlet distortion on the primary parameters of the aero-engine. The paper presents rated estimation results in the context of twin spool turbofan design for two typical cruiser modes of flight of the supersonic passenger jet. In estimation the base values σbase and the average values of the inlet ram recovery σave remained invariable. Thus, parametrical calculations were performed for each chosen relative value of the area of low-pressure region.The paper shows that an impact degree of the inlet distortion on the engine thrust for two modes under consideration is essentially different. In other words, if in the subsonic mode the impact assessment can be confined only to taking into account the influence of decreasing average values of the inlet total pressure, the use of such an assumption in the supersonic cruiser mode may result in considerable errors.With invariable values of the pressure recovery factor at the engine intake, which correspond to the speed of flight for a typical air inlet of external compression σbase, and average value σave, a parameter Δσuneven has the main effect on the engine thrust, and degree of this effect essentially depends on a difference between σave and σbase values.

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Rise of total pressure near the stagnation point on a sphere

AIAA Journal ◽

10.2514/3.15099 ◽

2002 ◽

Vol 40 ◽

pp. 576-579

Author(s):

J. C. Williams III

Keyword(s):

Stagnation Point ◽

Total Pressure

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The Eﬀect of Interest, Religious Stimuli, and the Consumer’s Trust on the Digital Al Qur’an Purchase

International Journal of Islamic Business and Economics (IJIBEC) ◽

10.28918/ijibec.v2i2.1307 ◽

2018 ◽

pp. 89

Author(s):

Sokhikhatul Mawadah ◽

Nurudin Nurudin

Keyword(s):

P Value ◽

Dominant Effect ◽

Purchasing Decision ◽

A Company

PT Tigaraksa Satria branch of Semarang, is a company which runs the digital Al Qur’an product as one of its type of business’s engagement. One of the digital Al Qur’an to be sold is Mushaf Grand Maqomat. PT Tigaraksa Satria also produces Mushaf for Woman and Mushaf Maqomat for Kids. Among these three Mushaf, Mushaf Grand Maqomat-has the less selling. This study is expected to measure and analyzing the effect of interest, religious stimuli, and consumers’ trust on the decision to purchase digital Al Qur’an. It is suspected that variable of religious stimuli has the most dominant effect to the consumers. The population in this study are the current consumers of digital Al Qur’an on PT Tigaraksa Satria. The result of this study indicates that variable of interest has significant effect on the purchasing’s decision. This is resulted on p-value (sig) that is 0.001 under 0.05, the variable of stimuli has significant effect on purchasing decision indicated by 0.755 as the p-value (sig) above 0.05. Whilst, the most dominant variable that influences buyers in purchasing Al Qur’an is the religious stimuli, accordingly to the researcher’s hypothesis that states religious stimuli is the most dominant variable.

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G × E interaction studies in relation to heterosis and stability of grain yield in maize (Zea mays L.)

Indian Journal of Genetics and Plant Breeding (The) ◽

10.31742/ijgpb.80.3.3 ◽

2020 ◽

Vol 80 (03) ◽

Author(s):

K. Sumalini ◽

T. Pradeep ◽

D. Sravani

Keyword(s):

Grain Yield ◽

Zea Mays L ◽

Yield Stability ◽

Superior Performance ◽

Dominant Effect ◽

Stability Parameters ◽

Hybrid Classes ◽

Maize Inbreds ◽

Comparative Stability ◽

Potential Use

Interaction of homozygous inbreds and heterozygous single, three way and double crosses with environment had shown a differential response in achieving yield stability. Seven diverse maize inbreds, their 21 single crosses and 105 each of three way and double crosses obtained through diallel were evaluated for twelve characters across three diverse locations to estimate comparative stability of homozygous and heterozygous genotypes for grain yield. Contrasts in heterobeltiosis, combining ability and stability parameters in three environments and interaction effects were observed. Gain in heterobeltiosis (%) for grain yield was observed with decreased environmental quality in different hybrid classes suggesting that heterozygous hybrids are more stable due to individual buffering in single crosses and both individual and population buffering in case of three way and double crosses. Significant increase in SCA effects was observed in moderate environment at Hyderabad rather than at high yielding environment Palem. Significant G × E and Environment (linear) in all the crosses was observed for grain yield suggesting the effect of environment and its pre dominant effect on grain yield. Stability of hybrids was attributed to their superior performance over the parents in low yielding environment. Thus the potential use of selected heterozygous hybrids would allow under diverse environments is suggested to mitigate losses arising out of climate change.

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