Browsing by Author "HUANG, CC"

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BUOYANCY-INDUCED FLOW TRANSITION IN MIXED CONVECTIVE FLOW OF AIR THROUGH A BOTTOM HEATED HORIZONTAL RECTANGULAR DUCT
(1994-05-01)
HUANG, CC
;
LIN, TF
;
交大名義發表
;
機械工程學系
;
National Chiao Tung University
A detailed numerical simulation was carried out to study the buoyancy induced flow transition in a mixed convective flow of air through a bottom heated horizontal rectangular duct. The unsteady three-dimensional Navier-Stokes and energy equations were directly solved by a higher order finite difference numerical scheme without using any turbulence modeling. Results were particularly presented for Re = 500 and A = 2 covering a wide range of Gr/Re2 from steady laminar longitudinal vortex now to unsteady chaotic flow. The results indicate that the increasing buoyancy causes the steady laminar flow for Gr/Re2 < 4 to become a periodic laminar flow for 4 less-than-or-equal-to Gr/Re2 < 19, then to a quasiperiodic flow for 19 less-than-or-equal-to Gr/Re2 < 25 and finally to a chaotic flow in the downstream for 25 < Gr/Re2 less-than-or-equal-to 40. Thus, the buoyancy induced laminar to turbulent flow transition follows the Ruelle-Taken route. An empirical equation was proposed to correlate the locations for Hopf bifurcation.
COMPUTER-SIMULATION OF A DIRECT SEQUENCE SPREAD SPECTRUM CELLULAR RADIO ARCHITECTURE
(1992-11-01)
HUANG, CC
;
交大名義發表
;
電信工程研究所
;
National Chiao Tung University
;
Institute of Communications Engineering
This paper describes a computer simulation study to evaluate the channel capacity of a direct sequence spread spectrum cellular radio architecture which is based on code division. The cellular radio architecture utilizes the processing pin provided by a wide-band multipath RAKE receiver to suppress multicell/multiuser interference. As a result, the same piece of radio spectrum can be reused in every cell. We use a step-by-step approach to verify the basic idea behind the spread spectrum cellular radio architecture. Computer simulations are used to calculate the distributions of signal-to-reference ratio (SIR). From SIR distributions, we can easily calculate the channel capacity of the cellular radio architecture. Technical requirements to fulfill potential system performance are also discussed. Finally, an 800 MHz system example is given for cellular mobile radio telephone application.
Factors affecting remote positioning performance
(1995)
HSU, SH
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HUANG, CC
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工業工程與管理學系
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Department of Industrial Engineering and Management
LOW-PRESSURE CHEMICAL VAPOR-DEPOSITION OF TIN AND ZRN THIN-FILMS FROM TI(NET2)4 AND ZR(NET2)4
(1990-08-26)
CHIU, HT
;
HUANG, CC
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應用化學系
;
Department of Applied Chemistry
LOW-PRESSURE CHEMICAL VAPOR-DEPOSITION OF TITANIUM AND ZIRCONIUM CARBONITRIDE THIN-FILMS FROM M(NET2)4 (M = TI AND ZR)
(1993-04-01)
CHIU, HT
;
HUANG, CC
;
交大名義發表
;
應用化學系
;
National Chiao Tung University
Ti (NEt2)4 and Zr (NEt2)4 were used as single-source precursors to deposit titanium and zirconium carbonitride thin films on Si( 100) and glass substrates at temperatures 673-923 K by low-pressure chemical vapor deposition. The thin films were analyzed by X-ray diffraction, scanning electron microscopy, X-ray photoelectron spectroscopy, wavelength dispersive spectroscopy, and infrared spectroscopy. The films deposited at high temperatures crystallized into cubic structures as shown by X-ray diffraction. The nitrogen-to-metal ratios were close to unity in most cases while the carbon-to-metal ratios decreased with increasing deposition temperature. At deposition temperatures below 773 K, hydrocarbon stretchings were observed by IR, Attempts to decrease carbon levels in thin films by adding H-2 into the carrier gas showed opposite effects.
TRANSIENT BINARY MIXTURE NATURAL-CONVECTION IN SQUARE ENCLOSURES
(1990-02-01)
LIN, TF
;
HUANG, CC
;
CHANG, TS
;
交大名義發表
;
機械工程學系
VORTEX FLOW AND THERMAL-CHARACTERISTICS IN MIXED CONVECTION OF AIR IN A HORIZONTAL RECTANGULAR DUCT - EFFECTS OF THE REYNOLDS AND GRASHOF NUMBERS
(1995-06-01)
HUANG, CC
;
LIN, TF
;
機械工程學系
;
Department of Mechanical Engineering
A three-dimensional unsteady numerical simulation was carried out to study the effects of Reynolds and Grashof numbers on the vortex flow structure and thermal characteristics in a buoyancy-induced time periodic mixed convective air flow through a bottom heated horizontal rectangular duct. The unsteady Navier-Stokes equations along with the continuity and energy equations were integrated by the Projection method with the convective and diffusive terms discretized by higher order finite difference schemes. Results for the Reynolds number varied from 1000 to 200 at a fixed Grashof number clearly show the splitting and merging of the longitudinal rolls. The flow destabilizes during the processes of roll merging and splitting. After the merging and splitting the flow gradually stabilizes as it moves downstream. For the Reynolds number at 100, stable thermal stratification appears in the upper half of the duct and the flow oscillation is significantly suppressed there.