Numerical assessment of four-part through-flow wave rotor cycles with passage height variation

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National Aeronautics and Space Administration, National Technical Information Service, distributor , [Washington, DC], [Springfield, Va
Computational fluid dynamics., Flow distribution., Ro
Other titlesNumerical assessment of four part through-flow wave rotor cycles with passage height variation.
StatementD.E. Paxson and Jules W. Lindau.
SeriesNASA technical memorandum -- 107490.
ContributionsLindau, Jules W., United States. National Aeronautics and Space Administration.
The Physical Object
Pagination1 v.
ID Numbers
Open LibraryOL15503719M

Wave diagrams as well as on and off-design performance data will then be presented and compared with that from a constant cross section passage for a four-port, through-flow cycle designed to top a small helicopter engine with a mass flow rate of approximately lbm/s, and an upstream compressor pressure ratio of File Size: 1MB.

Numerical assessment of four-part Numerical assessment of four-part through-flow wave rotor cycles with passage height variation book wave rotor cycles with passage height variation (OCoLC) Material Type: Document, Government publication, National government publication, Internet resource: Document Type: Internet Resource, Computer File: All Authors / Contributors: Daniel E Paxson; Jules W Lindau; Lewis Research Center.

Get this from a library. Numerical assessment of four-part through-flow wave rotor cycles with passage height variation. [Daniel E Paxson; Jules W Lindau; United States.

National Aeronautics and Space Administration.]. The objective of this paper is to provide a succinct review of past and current research in developing wave rotor technology. This technology has shown unique capabilities to enhance the performance and operating characteristics of a variety of engines and machinery utilizing thermodynamic by: loads during surge cycles.

During surge cycles the flow breaks down completely in the compressor. This is aerodynamically and mechanically undesirable since parts of the rotor can be damaged and the whole cycle operation may be affected. Fur-thermore, it results in high temperatures, high levels of vibra-tion and leads to flow reversal.

The Rampressor rotor impeller can be developed with two, three, four, or more inlets according to the Rampressor flow. The Rampressor rotor model in this study is established with three inlet flow paths as shown in Figure 1.

The supersonic rotor flow path is formed by three strakes mounted on the rim of the : Weijia Kang, Zhansheng Liu, Jiangbo Lu, Yu Wang, Yanyang Dong. A numerical analysis has been conducted in order to simulate the characteristics of complex flow through linear cascades of high performance turbine blade with/without tip clearance by using a pressure-correction based, generalized 3D incompressible Navier-Stokes CFD code.

The development and generation of horseshoe vortex, passage vortex, leakage vortex, tip vortex within tip Cited by: 3. A numerical model has been developed at the NASA Lewis Research Center which can predict both the unsteady flow quantities within a wave rotor passage and the steady averaged flows in the ports.

rotor are of the greatest concern. Most often, they represent the lowest modes of the entire machine structure.

Details Numerical assessment of four-part through-flow wave rotor cycles with passage height variation FB2

Next, through the supporting bearings and through the fluid encircling the rotor (unless the rotor operates in vacuum), the rotor lateral vibrations are. Physics. STUDY. Flashcards. Learn. Write. Spell. Test. PLAY. Match. Gravity.

Created by. bigdog Terms in this set (25) Phase. A single part of a cycle. in-phase. When two waves are at the same part of their cycle.

out-of-phase. When two waves are at different parts of their cycle. Damping. The process of harmonic motion losing amplitude over. 7 and 8 show, respectively, the phase-averaged velocity distributions in and around the rotating Savonius rotors at two typical rotor angles 0 = 0and 90 Each figure shows the measurements and numerical calculations for the rotors at various overlap ratios (OL = 0, ).Cited by: Rotor assembly with stationary seal plates [Left] Developed view of WRCVC [Right] Wave rotor constant volume combustor rig at Purdue Zucrow Lab Wave Rotor Cycle • High pressure hot exhaust gas purged from the passages when the passage opens to the exhaust port.

• Passage is filled with air-fuel mixture for the next combustion cycle. A numerical model has been developed which can predict the dynamic (and steady state) performance of a wave rotor, given the geometry and time dependent boundary conditions.

The one-dimensional, perfect gas, CFD based code tracks the gas dynamics in each of the wave rotor passages as they rotate past the various Size: KB. Acoustic wave can be reflected by a solid surface. If a travelling wave is reflected, the reflected wave can interfere with the incident wave causing a standing wave in the near field.

As a result, the local pressure in the near field is doubled, and the particle velocity becomes zero and flow becomes stagnant. The pattern of flow through a porous windbreak has been investigated numerically using several well-known closure schemes (turbulence models).

The shelter is included as a momentum extraction term in the streamwise momentum equation, for a fence having the value k r u | u |δ(x,0)s(z,H) where k r is the pressure-loss coefficient of the fence, ū is the local mean horizontal (x) velocity, δ(x Cited by: This is only apparent above ° yaw with an approximate 20% power reduction at ° yaw [8].

This is a noticeable difference and is likely to be higher than the 20% suggested because the rotor experiences a reduced effective velocity in yawed flow, hence reduced TSR.

- - Spalart-Allmaras turbulent model [10]. The k – ω SST is a two equations turbulent model, which combines the excellent modeling of the main flow provided by the k – ε model and the reliable near wall modeling of the flow provided by the k – ω model [8, 7].

By incorporating the. k – ω. SST. model, Abraham et al.

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[1] carried out an 2D numericalFile Size: 1MB. Table 1 Comparison of numerical results for flow past a stationary triangular cylinder at Re = Studies CD, mean CL, rms St De and Dalal () Alawadhi () - The present The solution procedure based on the fractional step algorithm can be described here as: (i) solve : Q.

Zhai, H. Wang, G. The influence on the flow pattern of the gradual passage opening in the wave rotor is studied on the basis of numerical simulation. It is found that, in most cases, significant volume of the. Three-Dimensional Numerical Analysis of Internal Flow Phenomena 29 2.

Fan geometry and design specifications The diagonal rotor analyzed in this study is widely used in engineering. It was designed by the modified quasi three-dimensional method. The design format utilized a streamline curvature to determine the average stream surface by.

NUMERICAL MODEL The real flow structures within rotor passage could not account by 1D analysis so, 3D numerical investigation was carried out using ANSYS-CFX software. A single passage model was used with periodic interface to account the domain motion.

The rotor- shroud clearance was considered as 5% of the rotor blade : Samip Shah, Salim Channiwala, Digvijay Kulshreshtha, Gaurang Chaudhari. Numerical results are achieved by applying of the continuity equation taking into account any type of flow regime in the interface vicinities.

The four equations that consider the direction of wavefront propagation and the type of pressurized or depressurized wavefront.

Description Numerical assessment of four-part through-flow wave rotor cycles with passage height variation PDF

Electromagnetic Waves. Do not require a medium; can travel through a medium, electric and magnetic fields vibrate to carry the energy. Amplitude of a Wave. Height of the wave indicates how much energy the wave is carrying.

The model considered here is a reverse-flow wave disc with 60 straight channels as shown in Fig. The disc has an inner radius of m and an outer radius of m, rotating clockwise at rpm. Two sets of four ports, as in a conventional four-port pressure exchanger, are used. Rotor Track and Balance Improvements Eric Bechhoefer1, Austin Fang2 and Ephrahim Garcia2 1Green Power Monitoring Systems, LLC, Vermont,USA [email protected] 2Cornell University, Ithaca, New York,USA [email protected] [email protected] ABSTRACT Vibration derived from the main rotor dynamics andFile Size: 2MB.

Flow over a circular cylinder at Reynolds number is studied numerically using the technique of large eddy simulation. The computations are carried out with a high-order accurate numerical method based on B-splines and compared with previous upwind-biased and central finite-difference simulations and with the existing experimental data.

In the very near wake, all three simulations are in Cited by: Statistics based models have been developed previously to predict a priori the performance of new radial flow compressors and pumps and to model test data of previously designed and tested machines.

Unfortunately, critical dynamics in the inlet region of the machines were neglected. Consequently, room for improvement in the previous modeling : Nathan O. Packard. The performance equations of an induction motor are given in the rotor reference frame of two of the three phases.

These equations are used to analyse the steady state performance of an induction motor with square wave currents in the rotor and sinusoidal voltages on the stator.

A closed form solution for stator flux linkages in the time domain is obtained using state transition signal flow Cited by: 1. Wave rotor machinery represents a promising technology that can enhance cycle power and efficiency, plus possibly reduce the overall size, weight and cost.

It allows a higher cycle peak temperature without need for a cooling system. Furthermore, the rotational speed of a wave rotor. refined variation asymptotic method and Hamilton’s principle.

The numerical results determined by Galerkin method are analyzed to indicate the effects of ply angle, taper ratio, and transverse shear total deformation on the first natural frequency and critical rotating speed. MODELING AND ANALYSISFile Size: KB.

NUMERICAL AND EXPERIMENTAL STUDY OF A FLOW NUMERICAL AND EXPERIMENTAL STUDY OF A FLOW OVER STRAIGHT AND SWEPT HIGH-LIFT WINGS 5 OVER STRAIGHT AND SWEPT HIGH-LIFT WINGS and influence of the cross flow in the stagnation zone. At high angles of attack = 17º consider the influence of main parameters only.(Fig.

8) in. This paper presents numerical simulations of a circular cylinder under the action of current or wave only. The model solves the three-dimensional (3D) Reynolds-averaged Navier-Stokes equations using an explicit projection method.

The 3D grid system is made of lots of prisms, which are built from a two-dimensional horizontal triangular grid by adding a number of horizontal layers.By using MIKE21SW module to simulate the waves, the paper explores the influence of bottom friction parameter and wave breaking parameter on wave height and wave period.

The law for future MIKE21 parameter calibration is : Jin Song Gui, Ming Wei Feng, Rui Jin Zhang.