Because of the potential technical advantages, the contrarotation technology has become a renewed interest in aviation and other applications. Experimental investigation of a counterrotating compressor with. Generally, maximum pressure ratio achieved in a stage of axial compressor is about 1. Contrarotating propellers have been found to be between 6% and 16% more efficient than normal propellers. Investigation of the unsteady disturbance in tip region of a. Another benefit of counterrotation is that it offers a much larger change. In so doing, the compressor 14 allow for components of conventional non axial compressor stages, such as diffuser pipes or stators, to be removed from the gas turbine engine 10. The original transient fluctuation and oscillation of the tip leakage vortex structure with varying flow capacity of the. The turbine engine includes a row of stator vanes arranged between two rows of rotor blades of the drum of the compressor, so as to straighten the flow and improve the efficiency. Design of a novel axial impeller as a part of counter. Previous numerical simulations reveal that the counter rotating compressor experiences serious. A planetary gear system is assembled along a static casing, which can be. The z axis is along the axis of rotation which is along the running length of the compressor shaft, the radius r is measured outward from the shaft.
The compressor is composed of three counterrotating, aspirated stages and has a pressure ratio of 27. It is a rotating, airfoilbased compressor in which the gas or working fluid principally flows parallel to the axis of rotation, or axially. A study of speed ratio affecting the performance of a contrarotating axial compressor yy chen, b liu, y xuan, and xr xiang proceedings of the institution of mechanical engineers, part g. Moore cornell university ithaca, new york prepared for lewis research center under intergovernmental personnel agreement 8 1 o62 6 1 national aeronautics and space administration scientific and technical information branch 1983. Such a jet engine would have contra rotating turbines, or contra rotating compressors, or both. A study of aerodynamic performance of a contrarotating. Experimental investigation on the stall inception of a. The total pressure at the inlet is artificially distorted by means of two different sets of screens with different porosities to generate a hubstrong. Because of the counter rotating technique, kinematic energy in the.
The aspirated counter rotating compressor was designed using a onedimensional stage analysis program coupled with an axisymmetric throughflow code and a quasithreedimensional cascade code for blade design. In fact i cannot think of even one aircraft that has this. The internal flow condition between the front and rear rotors of the contra rotating smallsized fan is not known well especially at the low flow rate. Presented at the international gas turbine and aeroengine congress and exposition. An axial compressor is a gas compressor that can continuously pressurize gases. The compressor has alternating rows of impellers, with each successive row of impellers being mounted a central hub or to an outer sleeve. Comparison of counterrotating and traditional axial aircraft lowpressure turbines integral and detailed performances. Aug 28, 2019 variable torque split aircraft gas turbine engine counter rotating low pressure turbines.
Transient numerical simulation was carried out in a single passage of the crac. In recent years, the contrarotating axial fancompressor arouse a greater interest that contrarotation enables to simplify machine structure and. Axial compressor design with counterrotation and variable rpm. This manual does not for designing centrifugal compressor and those parts.
Counterrotation is used to push compressor performance during stall by moving the operating point away from surge line with a higher pressure ratio rise. Compressor of axial turbine engine with contrarotating rotor. Variable torque split aircraft gas turbine engine counter rotating low pressure turbines. Contra rotating compressor rotors are known to process higher mass flows than a regular axial compressor for same flow area. Rotor 1 and rotor 2 had 19 and 17 blades, respectively. Contrarotation increases efficiency in comparison with the singlerotor design, but this advantage is not fully harnessed.
Aerodynamic design of an aspirated counterrotating. School of engines and energy, northwestern polytechnical university, xian. The aspirated counterrotating compressor was designed using a onedimensional stage analysis program coupled with an axisymmetric throughflow code and a quasithreedimensional cascade code for blade design. Structural and conceptual design analysis of an axial. The two, counterrotating, compressor rotors may also help to orient the flow of the compressed fluid to be in an axial direction. A study of aerodynamic performance of a contra rotating. Design parameters of the counter rotating axial fan. Contra rotating smallsized axial fans are used as cooling fans for electric equipment. Experimental investigation of a counterrotating compressor. A working model of a low speed contrarotating 4stage mini axial compressor has been developed to demonstrate its multifarious benefits over a conventional axial compressor that matches all the.
Pdf a study of aeroacoustic performance of a contrarotating. School of energy science and engineering, harbin institute of technology, harbin 150001, china. If some propengines have contrarotators, i dont see why some jets dont have it either. A counterrotating turbine means that blade rows are joined to two shafts with opposite. Internal flow condition between front and rear rotor of.
Axial compressor design with counterrotation and variable. All three blade rows plus the aspiration slot and plenum were included in the computational domain. A theory of rotating stall of multistage axial compressors loan copy. The present paper numerically conducted fullannulus investigation on the effects of circumferential total pressure inlet distortion on the performance and flow field of. Pdf design and development of low speed 4stage axial. A study of speed ratio affecting the performance of a contra. Avoidance of severe axial compressor rotating stall prevention of blade rubbing in the compressor or turbine due to an increased rate of thermal expansion and vibration although these are all important issues, this paper focuses only on the issue of axial compressor rotating stall during startup as shown highlighted in red in figure 1. Investigation of the unsteady disturbance in tip region of a contra. Because of the counter rotating technique, kinematic energy in the tangential direction can be converted into static pressure. This design is further expounded upon in section 2. Nas37618 technical management nasa lewis research center. The torque on the aircraft from a pair of contra rotating propellers effectively cancels out.
Effect of inlet distortion on the performance of axial. Such a jet engine would have contrarotating turbines, or contrarotating compressors, or both. Air flows axially into the compressor which has rotating blades on the discs and stationary vanes to direct the. The early exploration of a low speed counter rotating axial compressor in the early 1990s 1 gave a first glimpse of the influence of parameters on the aerodynamic performance. A study of aerodynamic performance of a contrarotating axial compressor stage. Find counter rotating centrifugal compressor related suppliers, manufacturers, products and specifications on globalspec a trusted source of counter rotating centrifugal compressor information. Previous numerical simulations reveal that the counterrotating compressor experiences serious.
In so doing, the compressor 14 allow for components of conventional nonaxial compressor stages, such as diffuser pipes or stators, to be removed from the gas turbine engine 10. Contra rotating wet gas compressor framo engineering as. Apr 14, 2016 the disc and the drum are connected to different parts of the epicyclic reducing gears, so as to be counter rotating. A working model of a low speed contra rotating 4stage mini axial compressor has been developed to demonstrate its multifarious benefits over a conventional axial compressor that matches all the. The torque on the aircraft from a pair of contrarotating propellers effectively cancels out. Pdf thermodynamic potential of using a counter rotating. Mar 16, 2017 the two, counter rotating, compressor rotors may also help to orient the flow of the compressed fluid to be in an axial direction. You may obtain better results by changing your search criteria, using our search tips or consulting the alphabetical list of terms. In the case of the contrarotating rotors, the blade row distance between front and rear rotors is a key parameter for the performance and stable operation. The total pressure at the inlet is artificially distorted by means of two different sets of screens with different porosities to generate a hubstrong complex distortion and a tipstrong complex distortion. Counter rotating impellers, or rotating of rotors in opposite directions, is one of the promising approaches for substantial improvement in aerodynamic performance of an axial flow compressor stage. Design of a novel axial impeller as a part of counter rotating axial compressor to compress water vapor as refrigerant. Proceedings of the institution of mechanical engineers, part g.
The axial spacing of twostage contrarotating blade rows has a significant impact on a contrarotating fancompressor. Pdf a study of aerodynamic performance of a contrarotating. Pdf the paper reports of an experimental investigation into the aeroacoustic performance of a contrarotating axial flow compressor stage having a. Air flows axially into the compressor which has rotating blades. Counter rotating turbine crt is an axial turbine with nozzle followed by a. Within the framework of the eu funded project vital, snecma group safran, as the work package leader, developed a counter rotating lowspeed fanconcept for a high bypass ratio engine. The present paper numerically conducted fullannulus investigation on the effects of circumferential total pressure inlet distortion on the performance and flow field of the axial transonic counter rotating compressor. Influence of design parameters on the global performances of. In the case of the contra rotating rotors, the blade row distance between front and rear rotors is a key parameter for the performance and stable operation. Pdf a study of aerodynamic performance of a contra.
Tiwari, madhur, axial compressor design with counterrotation and variable rpm for stall mitigation. A multistage axial compressor incorporating a counterrotational movement is provided with a series of rotors mounted along and driven by a driveshaft, and a geared counterrotating outer casing. Contrarotating smallsized axial fans are used as cooling fans for electric equipment. A planetary gear system is assembled along a static casing, which can be assembled as a forward or aft casing for the compressor.
Thermodynamic potential of using a counter rotating novel axial impeller to compress water vapor as refrigerant. This will be beneficial in terms of fuel consumption with more thrustweight ratio. Numerical simulation of unsteady aerodynamic interactions of contra. Us9534608b2 multistage axial compressor with counter. Another benefit of counter rotation is that it offers a much larger change. A counter rotating wet gas compressor for deployment and operation on the sea floor is described. A theory of rotating stall of multistage axial compressors f. The design and testing of a 400 mm diameter contrarotating fan. An unsteady analysis of the mit counterrotating aspirated compressor crac has been conducted using the numeca fineturbo 3d viscous turbulent solver with the nonlinear harmonic nlh method. Contra rotating smallsized fans are used as cooling fans for electric equipment. There are two main types of compressors used in modern jet engines.
First since they extract energy from the flow rather than adding it, the pressure drops throughout a turbine. Observations of the growth and decay of stall cells during stall and surge in an axial compressor international journal of rotating machinery, vol. Design and development of a multi stage contra rotating mini. Prediction of rotating stall during start up for axial. Initially an axial compressor is designed with counterrotation at design point. A study of speed ratio affecting the performance of a contra rotating axial compressor yy chen, b liu, y xuan, and xr xiang proceedings of the institution of mechanical engineers, part g. The design volume flow is 64 m3s, and the other main design parameters of the crf are shown in table 1. However they differ from compressors in some important ways. Unsteady simulations of a counterrotating aspirated compressor. Initially an axial compressor is designed with counter rotation at design point. Sep 01, 2011 read design of a novel axial impeller as a part of counter rotating axial compressor to compress water vapor as refrigerant, applied energy on deepdyve, the largest online rental service for scholarly research with thousands of academic publications available at your fingertips.
Aircraft gas turbine engine with control vanes for counter rotating low pressure turbines. Counter rotation is used to push compressor performance during stall by moving the operating point away from surge line with a higher pressure ratio rise. A theory of rotating stall of multistage axial compressors. The compressor is composed of three counter rotating, aspirated stages and has a pressure ratio of 27. The bearings of the planetary gear system typically will be aligned. Because of the novel technique, an unusual set of constraints required a simplified 1 and 2d design methodology to be developed and investigated through cfd. Flow studies in ducted twinrotor contrarotating axial flow fans. Rotating stall suppression in axial compressors with casing. Contra rotating propellers have been found to be between 6% and 16% more efficient than normal propellers. Design and development of a multi stage contra rotating. However they can be very noisy, with increases in noise in the axial forward and aft direction of up to 30 db, and tangentially 10 db. Design of a novel axial impeller as a part of counterrotating axial compressor to compress water vapor as refrigerant. Experimental investigation of steady and unsteady flow field.
Axial flow compressor stators located in the casing as with other types of rotating machinery, an axial compressor can be described in a cylindrical coordinate system. You may obtain better results by changing your search criteria, using our. The compressor resulting from the analysis presented in this paper is shown in figure 1. It is a rotating, airfoilbased compressor in which the gas or working fluid principally flows parallel to. Degree of reaction turbines behave according to the same principles of dynamic energy exchange as compressors. Inlet guide vanes optional on some models, inlet guide vanes can be installed to improve performance at partial load conditions. A multistage axial compressor incorporating a counter rotational movement is provided with a series of rotors mounted along and driven by a driveshaft, and a geared counter rotating outer casing. All three blade rows plus the aspiration slot and plenum were included in. The internal flow condition between the front and rear rotors of the contrarotating smallsized fan is not known well especially at the low flow rate. The ind100 has a sixteen stage axial compressor and a vigv for part load operation, with a constant hub diameter annulus configuration and operating at isosls conditions as shown in figure 1. The present study investigated the spectrum characteristics of unsteady disturbance and the tip leakage vortex evolution during prestall process for a contrarotating axial compressor crac. Unsteady flow condition between front and rear rotor of. Read design of a novel axial impeller as a part of counterrotating axial compressor to compress water vapor as refrigerant, applied energy on deepdyve, the largest online rental service for scholarly research with thousands of academic publications available at your fingertips. Seven high response pressure sensors were mounted at the leading edge of rotor 1r1 and rotor 2r2 as well as at the outlet of r2 blade tip and root.
Experimental investigation of steady and unsteady flow field in a counterrotating axial fan lu huawei1, guo shuang1, gang hyungoo2 1. A counterrotating wet gas compressor for deployment and operation on the sea floor is described. The detailed aerodynamic and mechanical optimization of one blading version crtf2. Compressor performance has a large influence on total engine performance. Experimental investigation of a high aspect ratio, low speed.
A study of speed ratio affecting the performance of a contrarotating. The z axis is along the axis of rotation which is along the running length of the compressor shaft, the radius r. This paper focuses on the response of a high aspect ratio, low speed contrarotating fan with complex inflow distortion. Experimental investigation of a counterrotating compressor with boundary layer suction 1045. Us20140147243a1 contra rotating wet gas compressor. Effect of speed ratio on the performance and flow field of a. For investigating the flow phenomena in the stall process of a counterrotating compressor crc, static and dynamic experiment have been carried out on a low speed counterrotating compressor. Manual purpose to be used for selection, application into the system, power and cooling water estimation. Aug 28, 2019 the present study investigated the spectrum characteristics of unsteady disturbance and the tip leakage vortex evolution during prestall process for a contra rotating axial compressor crac. The bearings can be inspected and serviced without removing the coupling hub or breaking the casing joint. Contrarotating smallsized fans are used as cooling fans for electric equipment.
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