scholarly journals Investigation of Rotor Blade Roughness Effects on Turbine Performance

1993 ◽  
Vol 115 (3) ◽  
pp. 614-620 ◽  
Author(s):  
J. L. Boynton ◽  
R. Tabibzadeh ◽  
S. T. Hudson
Keyword(s):  
Surface Finish ◽  
Space Shuttle ◽  
Power Level ◽  
Rotor Blades ◽  
Machining Process ◽  
Inlet Temperature ◽  
Test Results ◽  
Roughness Effects ◽  
Turbine Efficiency ◽  
Swirl Angle

The cold air test program was completed on the SSME (Space Shuttle Main Engine) HPFTP (High-Pressure Fuel Turbopump) turbine with production nozzle vane rings and polished coated rotor blades with a smooth surface finish of 30 μin. (0.76 μm) rms (root mean square). The smooth blades were polished by an abrasive flow machining process. The test results were compared with the air test results from production rough-coated rotor blades with a surface finish of up to 400 μin. (10.16 μm) rms. Turbine efficiency was higher for the smooth blades over the entire range tested. Efficiency increased 2.1 percentage points at the SSME 104 percent RPL (Rated Power Level) conditions. This efficiency improvement could reduce the SSME HPFTP turbine inlet temperature by 57 R (32 K), increasing turbine durability. The turbine flow parameter increased and the midspan outlet swirl angle became more axial with the smooth rotor blades.

scholarly journals Investigation of Rotor Blade Roughness Effects on Turbine Performance

1992 ◽  
Author(s):  
J. L. Boynton ◽  
R. Tabibzadeh ◽  
S. T. Hudson
Keyword(s):  
Surface Finish ◽  
Space Shuttle ◽  
Power Level ◽  
Rotor Blades ◽  
Machining Process ◽  
Inlet Temperature ◽  
Test Results ◽  
Roughness Effects ◽  
Turbine Efficiency ◽  
Swirl Angle

The cold air test program was completed on the SSME (Space Shuttle Main Engine) HPFTP (High Pressure Fuel Turbopump) turbine with production nozzle vane rings and polished coated rotor blades with a smooth surface finish of 30 microinch (0.76 micrometer) RMS (Root Mean Square). The smooth blades were polished by an abrasive flow machining process. The test results were compared with the air test results from production rough coated rotor blades with a surface finish of up to 400 microinch (10.16 micrometer) RMS. Turbine efficiency was higher for the smooth blades over the entire range tested. Efficiency increased 2.1 percentage points at the SSME 104 percent RPL (Rated Power Level) condition. This efficiency improvement could reduce the SSME HPFTP turbine inlet temperature by 57 degrees Rankine (32 degrees Kelvin) increasing turbine durability. The turbine flow parameter increased and the mid-span outlet swirl angle became more axial with the smooth rotor blades.

Results From High Temperature Turbine Test on the HPT of the AGTJ-100A

1984 ◽  
Author(s):  
Masashi Arai ◽  
Kiyomi Teshima ◽  
Sunao Aoki ◽  
Hiroyuki Yamao
Keyword(s):  
Experimental Investigation ◽  
High Pressure ◽  
High Temperature ◽  
Aerodynamic Performance ◽  
Inlet Temperature ◽  
Test Results ◽  
Mechanical Reliability ◽  
High Pressure Turbine ◽  
Turbine Inlet Temperature ◽  
Turbine Efficiency

An experimental investigation was conducted through the use of a High Temperature Turbine Developing Unit (HTDU) having the same two stage turbine as the high pressure turbine (HPT) of the AGTJ-100A, to ascertain the aerodynamic performance, cooling characteristics and mechanical reliability. The test was performed in three phases, and the maximum turbine inlet temperature was about 1,573 K. The test results showed that turbine efficiency was 90.2 %, the level of metal temperature for nozzles and blades was as expected, and there was little trouble with the hot parts. This paper will present these test results.

scholarly journals The Effect of Rotor Blade Thickness and Surface Finish on the Performance of a Small Axial Flow Turbine

1983 ◽  
Vol 105 (2) ◽  
pp. 377-382 ◽  
Author(s):  
R. J. Roelke ◽  
J. E. Haas
Keyword(s):  
Surface Finish ◽  
Rotor Blade ◽  
Axial Flow ◽  
Aerodynamic Performance ◽  
Rotor Blades ◽  
Performance Gain ◽  
Test Results ◽  
Blade Profile ◽  
Blade Thickness ◽  
Rough Surface Finish

An experimental investigation was conducted to determine the effect of blade profile inaccuracies and surface finish on the aerodynamic performance of a 11.15-cm tip dia turbine. The as-received cast rotor blades had a significantly thicker profile than the design intent and a fairly rough surface finish. Stage test results showed an increase of one point in efficiency by smoothing the surface finish and another three points by thinning the blade profiles to near the design profile. Most of the performance gain between the as-cast thick and the thinned rotor blades, both with the same surface finish, was attributed to reduced trailing edge losses of the recontoured blades.

Analysis of Variable Fluid Properties, Turbulent Annular Seals

1991 ◽  
Vol 113 (4) ◽  
pp. 694-702 ◽  
Author(s):  
Luis A. San Andres
Keyword(s):  
Space Shuttle ◽  
Power Level ◽  
Fluid Motion ◽  
Dynamic Force ◽  
Computationally Efficient ◽  
Roughness Effects ◽  
Reference Case ◽  
Numerical Predictions ◽  
Fluid Properties ◽  
Cryogenic Liquids

A computational analysis for calculation of the dynamic force response in turbulent flow annular pressure seals of arbitrary nonuniform clearance is presented. Cryogenic liquids are considered as barotropic. The fluid motion is described by a bulk flow model and Moody’s friction factor is introduced to accomodate surface roughness effects. The numerical solution scheme is computationally efficient and accurate for seal operation at arbitrary eccentricity ratios. Numerical predictions show good agreement with available experimental results. The effects of eccentricity and liquid properties on the performance of the Space Shuttle Main Engine High Pressure Fuel Turbopump interstage seal at full power level are discussed as a reference case.

scholarly journals Metal Machining—Recent Advances, Applications, and Challenges

Metals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 580
Author(s):  
Francisco J. G. Silva
Keyword(s):  
Surface Finish ◽  
Manufacturing Process ◽  
Dimensional Accuracy ◽  
Machining Process ◽  
High Dimensional ◽  
Manufacturing Processes ◽  
Recent Advances ◽  
Metal Machining ◽  
Rapid Manufacture

Though new manufacturing processes that revolutionize the landscape regarding the rapid manufacture of parts have recently emerged, the machining process remains alive and up-to-date in this context, always presenting itself as a manufacturing process with several variants and allowing for high dimensional accuracy and high levels of surface finish [...]

Effects of Surface Finish and Loading Conditions on the Low Cycle Fatigue Behavior of Austenitic Stainless Steel in PWR Environment for Various Strain Amplitude Levels

2009 ◽  
Author(s):  
Jean Alain Le Duff ◽  
Andre´ Lefranc¸ois ◽  
Jean Philippe Vernot
Keyword(s):  
Stainless Steel ◽  
Austenitic Stainless Steel ◽  
Strain Amplitude ◽  
Surface Finish ◽  
Low Cycle Fatigue ◽  
Fatigue Behavior ◽  
Complex Loading ◽  
Loading Conditions ◽  
Test Results ◽  
Cycle Fatigue

In February/March 2007, The NRC issued Regulatory Guide “RG1.207” and Argonne National Laboratory issued NUREG/CR-6909 that is now applicable in the US for evaluations of PWR environmental effects in fatigue analyses of new reactor components. In order to assess the conservativeness of the application of this NUREG report, Low Cycle Fatigue (LCF) tests were performed by AREVA NP on austenitic stainless steel specimens in a PWR environment. The selected material exhibits in air environment a fatigue behavior consistent with the ANL reference “air” mean curve, as published in NUREG/CR-6909. LCF tests in a PWR environment were performed at various strain amplitude levels (± 0.6% or ± 0.3%) for two loading conditions corresponding to a simple or to a complex strain rate history. The simple loading condition is a fully reverse triangle signal (for comparison purposes with tests performed by other laboratories with the same loading conditions) and the complex signal simulates the strain variation for an actual typical PWR thermal transient. In addition, two various surface finish conditions were tested: polished and ground. This paper presents the comparisons of penalty factors, as observed experimentally, with penalty factors evaluated using ANL formulations (considering the strain integral method for complex loading), and on the other, the comparison of the actual fatigue life of the specimen with the fatigue life predicted through the NUREG report application. For the two strain amplitudes of ± 0.6% and ± 0.3%, LCF tests results obtained on austenitic stainless steel specimens in PWR environment with triangle waveforms at constant low strain rates give “Fen” penalty factors close to those estimated using the ANL formulation (NUREG/6909). However, for the lower strain amplitude level and a triangle loading signal, the ANL formulation is pessimistic compared to the AREVA NP test results obtained for polished specimens. Finally, it was observed that constant amplitude LCF test results obtained on ground specimens under complex loading simulating an actual sequence of a cold and hot thermal shock exhibits lower combined environmental and surface finish effects when compared to the penalty factors estimated on the basis of the ANL formulations. It appears that the application of the NUREG/CR-6909 in conjunction with the Fen model proposed by ANL for austenitic stainless steel provides excessive margins, whereas the current ASME approach seems sufficient to cover significant environmental effects for representative loadings and surface finish conditions of reactor components.

OPTIMISING CUTTING PARAMETERS FOR HOT TURNING ON EN31 MATERIAL

2021 ◽  
Vol 5 (10) ◽  
Author(s):  
Prof. Hemant k. Baitule ◽  
Satish Rahangdale ◽  
Vaibhav Kamane ◽  
Saurabh Yende
Keyword(s):  
Surface Roughness ◽  
Surface Finish ◽  
Cutting Speed ◽  
Cutting Parameters ◽  
Machining Process ◽  
Depth Of Cut ◽  
Multiple Time ◽  
Turning Process ◽  
Workpiece Material ◽  
Hot Turning

In any type of machining process the surface roughness plays an important role. In these the product is judge on the basis of their (surface roughness) surface finish. In machining process there are four main cutting parameter i.e. cutting speed, feed rate, depth of cut, spindle speed. For obtaining good surface finish, we can use the hot turning process. In hot turning process we heat the workpiece material and perform turning process multiple time and obtain the reading. The taguchi method is design to perform an experiment and L18 experiment were performed. The result is analyzed by using the analysis of variance (ANOVA) method. The result Obtain by this method may be useful for many other researchers.

As-Built Geometry and Surface Finish Effects on Fatigue and Tensile Properties of Laser Fused Titanium 6Al-4V

2017 ◽  
Author(s):  
Onome Scott-Emuakpor ◽  
Tommy George ◽  
Emily Henry ◽  
Casey Holycross ◽  
Jeff Brown
Keyword(s):  
Tensile Properties ◽  
Surface Finish ◽  
Fatigue Behavior ◽  
Turbine Blades ◽  
Material Behavior ◽  
Small Scale ◽  
Internal Cooling ◽  
Roughness Effects ◽  
Form And Function ◽  
And Function

The as-built material behavior of additive manufactured (AM) Titanium (Ti) 6Al-4V is investigated in this study. A solution heat treated, aged, stress relieved, and hot isostatic pressed Laser Powder Bed Fusion (LPBF) AM process was used to manufacture the specimens of interest. The motivation behind this work is based on the ever-growing desire of aerospace system designers to use AM to fabricate components with novel geometries. Specifically, there is keen interest in AM components with complex internal cooling configurations such as turbine blades, nozzle vanes, and heat exchangers that can improve small scale propulsion performance. Though it is feasible to three-dimensionally print parts that meet the Fit portion of a part characteristic description and identification, the Form and Function portions have proven to be more difficult to conquer. This study addresses both the Form and Function characteristics of the LPBF AM process via the investigation of geometry variation and surface roughness effects pertaining to mechanical properties and fatigue behavior of Ti 6Al-4V. Results show that geometry variation may be the cause of increased vibration fatigue life uncertainty. Also, both fatigue and tensile properties show profound discrepancies associated with surface finish. As-built surface finish specimens have lower fatigue and ductility performance, but the results are more consistent than polished data.

Rolls Royce/Allison 501-K Gas Turbine Anti-Fouling Compressor Coatings Evaluation

2002 ◽  
Author(s):  
Daniel E. Caguiat
Keyword(s):  
Gas Turbine ◽  
Fuel Consumption ◽  
Gas Turbines ◽  
Performance Degradation ◽  
Specific Fuel Consumption ◽  
Inlet Temperature ◽  
Test Results ◽  
Turbine Inlet ◽  
Compressor Performance ◽  
Compressor Efficiency

The Naval Surface Warfare Center, Carderock Division (NSWCCD) Gas Turbine Emerging Technologies Code 9334 was tasked by NSWCCD Shipboard Energy Office Code 859 to research and evaluate fouling resistant compressor coatings for Rolls Royce Allison 501-K Series gas turbines. The objective of these tests was to investigate the feasibility of reducing the rate of compressor fouling degradation and associated rate of specific fuel consumption (SFC) increase through the application of anti-fouling coatings. Code 9334 conducted a market investigation and selected coatings that best fit the test objective. The coatings selected were Sermalon for compressor stages 1 and 2 and Sermaflow S4000 for the remaining 12 compressor stages. Both coatings are manufactured by Sermatech International, are intended to substantially decrease blade surface roughness, have inert top layers, and contain an anti-corrosive aluminum-ceramic base coat. Sermalon contains a Polytetrafluoroethylene (PTFE) topcoat, a substance similar to Teflon, for added fouling resistance. Tests were conducted at the Philadelphia Land Based Engineering Site (LBES). Testing was first performed on the existing LBES 501-K17 gas turbine, which had a non-coated compressor. The compressor was then replaced by a coated compressor and the test was repeated. The test plan consisted of injecting a known amount of salt solution into the gas turbine inlet while gathering compressor performance degradation and fuel economy data for 0, 500, 1000, and 1250 KW generator load levels. This method facilitated a direct comparison of compressor degradation trends for the coated and non-coated compressors operating with the same turbine section, thereby reducing the number of variables involved. The collected data for turbine inlet, temperature, compressor efficiency, and fuel consumption were plotted as a percentage of the baseline conditions for each compressor. The results of each plot show a decrease in the rates of compressor degradation and SFC increase for the coated compressor compared to the non-coated compressor. Overall test results show that it is feasible to utilize anti-fouling compressor coatings to reduce the rate of specific fuel consumption increase associated with compressor performance degradation.

scholarly journals Numerical Investigation on the Influence of Hot Streak Temperature Ratio in a High-Pressure Stage of Vaneless Counter-Rotating Turbine

2007 ◽  
Vol 2007 ◽  
pp. 1-14 ◽  
Author(s):  
Zhao Qingjun ◽  
Wang Huishe ◽  
Zhao Xiaolu ◽  
Xu Jianzhong
Keyword(s):  
High Pressure ◽  
Secondary Flow ◽  
Heat Load ◽  
Rotor Blades ◽  
Inlet Temperature ◽  
Combined Effects ◽  
Temperature Ratio ◽  
Flow Angle ◽  
Hot Streak ◽  
Relative Flow

The results of recent studies have shown that combustor exit temperature distortion can cause excessive heat load of high-pressure turbine (HPT) rotor blades. The heating of HPT rotor blades can lead to thermal fatigue and degrade turbine performance. In order to explore the influence of hot streak temperature ratio on the temperature distributions of HPT airfoil surface, three-dimensional multiblade row unsteady Navier-Stokes simulations have been performed in a vaneless counter-rotating turbine (VCRT). The hot streak temperature ratios from 1.0 (without hot streak) to 2.4 were used in these numerical simulations, including 1.0, 1.2, 1.6, 2.0, and 2.4 temperature ratios. The hot streak is circular in shape with a diameter equal to 25%of the span. The center of the hot streak is located at 50%of span and 0%of pitch (the leading edge of the HPT stator vane). The predicted results show that the hot streak is relatively unaffected as it migrates through the HPT stator. The hot streak mixes with the vane wake and convects towards the pressure surface (PS) of the HPT rotor when it moves over the vane surface of the HPT stator. The heat load of the HPT rotor increases with the increase of the hot streak temperature ratio. The existence of the inlet temperature distortion induces a thin layer of cooler air in the HPT rotor, which separates the PS of the HPT rotor from the hotter fluid. The numerical results also indicating the migration characteristics of the hot streak in the HPT rotor are predominated by the combined effects of secondary flow and buoyancy. The combined effects that induce the high-temperature fluid migrate towards the hub on the HPT rotor. The effect of the secondary flow on the hotter fluid increases as the hot streak temperature ratio is increased. The influence of buoyancy is directly proportional to the hot streak temperature ratio. The predicted results show that the increase of the hot streak temperature ratio trends to increase the relative Mach number at the HPT rotor outlet, and decrease the relative flow angle from 25%to 75%span at the HPT rotor outlet. In the other region of the HPT outlet, the relative flow angle increases when the hot streak temperature ratio is increased. The predicted results also indicate that the isentropic efficiency of the VCRT decreases with the increase of the hot streak temperature ratio.

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