Study on Characteristics of Gas Flow Pressure in Catalytic Converter with Porous

2012 ◽  
Vol 235 ◽  
pp. 30-33
Author(s):  
Zhan Jun Cai ◽  
Wei Min Kang ◽  
Bo Wen Cheng ◽  
Ya Bin Li
Keyword(s):  
Porous Material ◽  
Gas Flow ◽  
Static Pressure ◽  
Pressure Field ◽  
Fiber Diameter ◽  
Catalytic Converter ◽  
Geometric Model ◽  
Center Line ◽  
Static Pressure Distribution ◽  
Flow Pressure

This paper studies the different porosity of porous medium how to affect the flow pressure field under the conditions of same inlet velocity and fiber diameter by CFDmethod. Geometric model of the catalytic converter has been established and meshed by the pre-processing tool of FLUENT. The flow pressure simulation filled contours and the curve of center line static pressure distribution of the fiber porous material show that in the case of other conditions remain unchanged, the less the porosity of the fiber porous material, the higher the inlet pressure and the more the pressure loss of the porous material. The more porosity of fiber is beneficial to exhaust catalytic reaction.

Study on Characteristics of Gas Flow in Catalytic Converter with Different Outlet Diameters

2014 ◽  
Vol 711 ◽  
pp. 16-19
Author(s):  
Zhan Jun Cai ◽  
Wei Min Kang ◽  
Ya Bin Li
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Catalytic Reaction ◽  
Gas Flow ◽  
Static Pressure ◽  
Catalytic Converter ◽  
Geometric Model ◽  
Flow Pressure ◽  
Different Diameters ◽  
Dynamics Method

. This paper studies the different diameters of tube outlet how to affect the gas flow pressure and velocity distribution in nanofiber catalytic converter by CFD (Computational Fluid Dynamics) method. Geometric model of the catalytic converter has been established and meshed by the pre-processing tool of FLUENT. The distribution of velocity and pressure in the converter which outlet diameter is 70 mm is more evenly than the converter which outlet diameter is 50 mm. It is conducive to reducing airflow static pressure in the catalytic converter that expanding the outlet diameter in the case of other conditions remains unchanged. Therefore, the larger outlet diameter is beneficial to exhaust catalytic reaction.

Study on Characteristics of Gas Flow Velocity in Catalytic Converter with Porous

2012 ◽  
Vol 229-231 ◽  
pp. 391-394
Author(s):  
Zhan Jun Cai ◽  
Wei Min Kang ◽  
Bo Wen Cheng ◽  
Ya Bin Li
Keyword(s):  
Porous Material ◽  
Flow Velocity ◽  
Gas Flow ◽  
Distribution Curve ◽  
Catalytic Converter ◽  
Geometric Model ◽  
Flow Speed ◽  
Cfd Method ◽  
Speed Simulation ◽  
Gas Flow Velocity

This paper studies the different porosity of porous medium how to affect the flow velocity field under the conditions of same inlet velocity and fiber diameter by CFD method. Geometric model of the catalytic converter has been established and meshed by the pre-processing tool FLUENT. The flow speed simulation filled contours and velocity distribution curve of the fiber porous material show that reducing properly the porosity may improve the uniformity of the velocity in Y and Z direction of the porous material. The less porosity is beneficial to exhaust catalytic reaction.

Measurement and Analysis of Static Pressure Field in a Torque Converter Pump

1995 ◽  
Vol 117 (1) ◽  
pp. 109-115 ◽  
Author(s):  
R. R. By ◽  
B. Lakshminarayana
Keyword(s):  
Pressure Distribution ◽  
Potential Flow ◽  
Static Pressure ◽  
Pressure Field ◽  
Pressure Rise ◽  
Torque Converter ◽  
Speed Ratio ◽  
Pump Speed ◽  
The Core ◽  
Static Pressure Distribution

In this paper, the static pressure field and performance parameters of a torque converter pump are measured, analyzed, and interpreted under three turbine/pump speed ratio conditions (0, 0.6, and 0.8). A potential flow code is used to predict the static pressure distribution. Results show that: 1) centrifugal force has a dominant effect on the static pressure rise in the pump; 2) the static pressure field is generally poor at the core section; and 3) the potential flow code can fairly well predict the static pressure distribution at the blade mid-span, but not at the core and shell sections.

Steady pressure-flow relationship of a model of the canine bronchial tree

1981 ◽  
Vol 51 (5) ◽  
pp. 1072-1079 ◽  
Author(s):  
D. B. Reynolds ◽  
J. S. Lee
Keyword(s):  
Reynolds Number ◽  
Pressure Drop ◽  
Kinetic Energy ◽  
Total Pressure ◽  
Gas Flow ◽  
Static Pressure ◽  
Bronchial Tree ◽  
Flow Pressure ◽  
Expiratory Flow ◽  
Relationship Of

Static pressure differences (deltaP) across the entire length and portions of a latex reproduction of a canine bronchial tree were measured during steady inspiratory or expiratory flow (V). The reproduction consists of a 10-cm length of trachea through bronchi of about 2 mm in diameter. The airflow was simulated by a water flow with tracheal Renolds number (Re0) in the range from 1,500 to 10,000. Loss in total pressure (deltaPt) was computed by summing deltaPt and V were well described (r greater than 0.98) by a dimensionless Rohrer equation deltaPt/deltaPd0 = A + B Re0 applicable to gas flow, in which deltaPd0 is a Poiseuille pressure drop. For expiratory deltaPt, A was about twice that for inspiration, while the values for B were nearly equal. Differences in kinetic energy between sites of static pressure measurement are important in determining loss in total pressure. Rohrer's equation is a good approximation to the phenomenological laws of steady inspiratory and expiratory flow-pressure relations in the canine bronchial tree for the range of Reynolds number investigated.

Effect of Clocking on the Second Stator Pressure Field of a One and a Half Stage Transonic Turbine

2004 ◽  
Author(s):  
J. Gadea ◽  
R. De´nos ◽  
G. Paniagua ◽  
N. Billiard ◽  
C. H. Sieverding
Keyword(s):  
Pressure Distribution ◽  
Static Pressure ◽  
Pressure Field ◽  
Pressure Fluctuations ◽  
Leading Edge ◽  
Fast Response ◽  
Time Resolved ◽  
Pressure Transducers ◽  
Static Pressure Distribution ◽  
Transonic Turbine

This paper focuses on the experimental investigation of the time-averaged and time-resolved pressure field of a second stator tested in a one and a half stage high-pressure transonic turbine. The effect of clocking and its influence on the aerodynamic and mechanical behaviour are investigated. The test program includes four different clocking positions, i.e. relative pitch-wise positions between the first and the second stator. Pneumatic probes located upstream and downstream of the second stator provide the time-averaged component of the pressure field. For the second stator airfoil, both time-averaged and time-resolved surface static pressure fields are measured at 15, 50 and 85% span with fast response pressure transducers. Regarding the time-averaged results, the effect of clocking is mostly observed in the leading edge region of the second stator, the largest effects being observed at 15% span. The surface static pressure distribution is changed locally, which is likely to affect the overall performance of the airfoil. The phase-locked averaging technique allows to process the time-resolved component of the data. The pressure fluctuations are attributed to the passage of pressure gradients linked to the traversing of the upstream rotor. The pattern of these fluctuations changes noticeably as a function of clocking. Finally, the time-resolved pressure distribution is integrated along the second stator surface to determine the unsteady forces applied on the vane. The magnitude of the unsteady force is very dependent on the clocking position.

Static pressure distribution in the free turbulent jet

1957 ◽  
Vol 3 (1) ◽  
pp. 1-16 ◽  
Author(s):  
David R. Miller ◽  
Edward W. Comings
Keyword(s):  
Static Pressure ◽  
Longitudinal Velocity ◽  
Fluid Motion ◽  
Mean Velocity ◽  
Free Jet ◽  
Static Pressure Distribution ◽  
Two Dimensional Flow ◽  
The Common ◽  
Jet Theory ◽  
Made In

Measurements of mean velocity, turbulent stress and static pressure were made in the mixing region of a jet of air issuing from a slot nozzle into still air. The velocity was low and the two-dimensional flow was effectively incompressible. The results are examined in terms of the unsimplified equations of fluid motion, and comparisons are drawn with the common assumptions and simplifications of free jet theory. Appreciable deviations from isobaric conditions exist and the deviations are closely related to the local turbulent stresses. Negative static pressures were encountered everywhere in the mixing field except in the potential wedge region immediately adjacent to the nozzle. Lateral profiles of mean longitudinal velocity conformed closely to an error curve at all stations further than 7 slot widths from the nozzle mouth. An asymptotic approach to complete self-preservation of the flow was observed.

Experimental Inverstigations On the Pressure Fluctuations in the Sealing Gap of Dry Gas Seals with Embedded Pressure Sensors

2021 ◽  
Author(s):  
Jingjing Luo ◽  
Dieter Brillert
Keyword(s):  
High Speed ◽  
Gas Flow ◽  
Static Pressure ◽  
Pressure Sensors ◽  
Operating Conditions ◽  
Test Facility ◽  
Experimental Investigations ◽  
Mechanical Seals ◽  
Process Gas ◽  
Sealing Gap

Abstract Dry gas lubricated non-contacting mechanical seals (DGS), most commonly found in centrifugal compressors, prevent the process gas flow into the atmosphere. Especially when high speed is combined with high pressure, DGS is the preferred choice over other sealing alternatives. In order to investigate the flow field in the sealing gap and to facilitate the numerical prediction of the seal performance, a dedicated test facility is developed to carry out the measurement of key parameters in the gas film. Gas in the sealing film varies according to the seal inlet pressure, and the thickness of gas film depends on this fluctuated pressure. In this paper, the test facility, measurement methods and the first results of static pressure measurements in the sealing gap of the DGS obtained in the described test facility are presented. An industry DGS with three-dimensional grooves on the surface of the rotating ring, where experimental investigations take place, is used. The static pressure in the gas film is measured, up to 20 bar and 8,100 rpm, by several high frequency ultraminiature pressure transducers embedded into the stationary ring. The experimental results are discussed and compared with the numerical model programmed in MATLAB, the characteristic and magnitude of which have a good agreement with the numerical simulations. It suggests the feasibility of measuring pressure profiles of the standard industry DGS under pressurized dynamic operating conditions without altering the key components of the seal and thereby affecting the seal performance.

Development of a Lifetime Pressure Sensitive Paint Procedure for High-Pressure Vane Testing

2021 ◽  
Author(s):  
Papa Aye N. Aye-Addo ◽  
Guillermo Paniagua ◽  
David G. Cuadrado ◽  
Lakshya Bhatnagar ◽  
Antonio Castillo Sauca ◽  
...  
Keyword(s):  
High Pressure ◽  
Test Section ◽  
Static Pressure ◽  
Pressure Field ◽  
Optical Measurements ◽  
Wall Region ◽  
Pressure Amplitude ◽  
Pressure Sensitive Paint ◽  
Suction Surface ◽  
Pressure Sensitive

Abstract Optical measurements based on fast response Pressure Sensitive Paint (PSP) provide enhanced spatial resolution of the pressure field. This paper presents laser lifetime PSP at 20 kHz, with precise calibrations, and results from a demonstration in an annular vane cascade. The laser lifetime PSP methodology is first evaluated in a linear wind tunnel with a converging-diverging nozzle followed by a wavy surface. This test section is fully optically accessible with maximum modularity. A data reduction procedure is proposed for the PSP calibration, and optimal pixel binning is selected to reduce the uncertainty. In the annular test section, laser lifetime PSP was used to measure the time-averaged static pressure field on a section of the suction surface of a high-pressure turbine vane. Tests were performed at engine representative conditions in the Purdue Big Rig for Annular Stationary Turbine Analysis module at the Purdue Experimental Turbine Aerothermal Lab. The 2-D pressure results showed a gradual increase of pressure in the spanwise and flow directions, corroborated with local static pressure taps and computational results. The variation in PSP thickness was measured as a contribution to the uncertainty. The discrete Fourier transform of the unsteady pressure signal showed increased frequency content in wind-on conditions compared to wind-off conditions at the mid-span and 30% span. Compared to the mid-span region, the hub end wall region had an increase in frequencies and pressure amplitude. This result was anticipated given the expected presence of secondary flow structures in the near hub region.

Ingestion Into the Upstream Wheelspace of an Axial Turbine Stage

1994 ◽  
Vol 116 (2) ◽  
pp. 327-332 ◽  
Author(s):  
T. Green ◽  
A. B. Turner
Keyword(s):  
Pressure Distribution ◽  
Static Pressure ◽  
Three Dimensional ◽  
Computer Code ◽  
Rotor Blades ◽  
Rotor Speed ◽  
Turbine Stage ◽  
Flow Rates ◽  
Static Pressure Distribution ◽  
Axial Clearance

The upstream wheelspace of an axial air turbine stage complete with nozzle guide vanes (NGVs) and rotor blades (430 mm mean diameter) has been tested with the objective of examining the combined effect of NGVs and rotor blades on the level of mainstream ingestion for different seal flow rates. A simple axial clearance seal was used with the rotor spun up to 6650 rpm by drawing air through it from atmospheric pressure with a large centrifugal compressor. The effect of rotational speed was examined for several constant mainstream flow rates by controlling the rotor speed with an air brake. The circumferential variation in hub static pressure was measured at the trailing edge of the NGVs upstream of the seal gap and was found to affect ingestion significantly. The hub static pressure distribution on the rotor blade leading edges was rotor speed dependent and could not be measured in the experiments. The Denton three-dimensional C.F.D. computer code was used to predict the smoothed time-dependent pressure field for the rotor together with the pressure distribution downstream of the NGVs. The level and distribution of mainstream ingestion, and thus the seal effectiveness, was determined from nitrous oxide gas concentration measurements and related to static pressure measurements made throughout the wheelspace. With the axial clearance rim seal close to the rotor the presence of the blades had a complex effect. Rotor blades in connection with NGVs were found to reduce mainstream ingestion seal flow rates significantly, but a small level of ingestion existed even for very high levels of seal flow rate.

Sign in / Sign up

Export Citation Format

Share Document