Browsing by Author "Huang, Szu-Chi"

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A new financial engineering model for analyzing the royalty of BOT projects: The Taiwan case
(2007)
Kang, Chao-Chung
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Feng, Cheng-Min
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Huang, Szu-Chi
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運輸與物流管理系註：原交通所+運管所
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Department of Transportation and Logistics Management
This paper uses the financial engineering concept to compare build, operate, and transfer (BOT) projects with non-BOT projects. The comparison reveals that there exists a difference in financial flow framework between BOT and non-BOT projects and that the benefit cost ratio (B/C) or self-liquidation ratio (SLR) cannot be used to analyze the financial plan although some earlier studies have used either of them to evaluate the financial feasibility of BOT projects. Moreover, this study construct a new financial investment evaluation model which includes the private construction cost ratio (PCCR), government construction cost ratio (GCCR), royalty, and government finance recovery ratio (GFRR) for analyzing the financial characters of BOT projects. In addition, this paper conducts a case study on the BOT concession of the Container Terminal in Taipei Port to find the solutions of PCCR, GCCR, royalty, and GFRR. Results of the case study show that the new BOT financial model could be used to interpret the financial characters of BOT projects.
Artificial Neural-Network-Based Pre-Distortion for High Loss-Budget 60-km Long-Reach Passive Optical Network
(2020-01-01)
Nguyen, Hong-Minh
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Huang, Szu-Chi
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Wei, Chia-Chien
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Chuang, Chun-Yen
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Chen, Jason Jyehong
High launch optical power can compensate for severe fading and power loss in long-reach passive optical networks (LR-PONs); however, it also aggravates nonlinear degradation, which necessitates the use of complex DSP-based nonlinear compensation techniques at optical network users (ONUs). DSP-related techniques also necessitate the use of additional hardware/software components by the receiver, which can greatly increase implementation costs and energy consumption, particularly when dealing with large-scale ONU deployment. This is the first study to propose artificial neural network (ANN)-based pre-distortion to eliminate the need for complex DSP at ONUs in a high-launch-power LR-PON, thereby permitting the use of a simplified architecture at the user end. In the first phase of the study, the proposed ANN-based pre-distortion scheme was implemented in a single-channel IMDD OFDM LR-PON, which achieved a data rate of >55 Gbps over 60-km transmission with a loss budget of 30 dB without the need for optical inline- or pre-amplification. In the second phase of experiments, the same scheme was applied to a 4-channel wavelength division multiplexing (WDM) OFDM LR-PON. Here, the proposed scheme achieved data rates of >200 Gbps using launch power of 18 dBm per lane, resulting in a loss budget of roughly 29 dB over 60-km single mode fiber transmission.
Channel orientation effect on endwall heat transfer in rotating cooling passages with pin-fins
(2019-06-01)
Huang, Szu-Chi
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Wang, Chen-Chih
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Liu, Yao-Hsien
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機械工程學系
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Department of Mechanical Engineering
Heat transfer was experimentally measured using a rotating pin-fin channel involving two channel orientations, namely 90 degrees and 150 degrees, with respect to a rotating axis. A rectangular channel with an aspect ratio of 4:1 was selected to study internal cooling near the trailing edge of a turbine blade. A newly developed method of liquid crystal thermography along with stroboscopic photography was used to obtain detailed heat transfer contours on an endwall surface. The pin-fin arrays were designed in either inline or staggered patterns, and the Reynolds number ranged from 5,000 to 20,000. The pressurized air flow acted as the working fluid, and the highest rotation number was thus 0.39. The influence of rotation was greater on the inline array than on the staggered array, engendering higher heat transfer enhancement on the leading and trailing surfaces. Compared with the other orientation, the inclined orientation (150 degrees) engendered a larger spanwise heat transfer variation because of the shifted rotation-induced secondary flows. The inline array exhibited the highest rotation-induced heat transfer enhancement at the 90 degrees orientation, and the highest enhancement levels were 90% and 40% on the trailing and leading surfaces, respectively. (C) 2019 Elsevier Ltd. All rights reserved.
EFFECT OF MISSING FIN ON ENDWALL HEAT TRANSFER IN A ROTATING COOLING CHANNEL
(2017-01-01)
Wang, Chen-Chih
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Huang, Szu-Chi
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Liu, Yao-Hsien
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機械工程學系
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Department of Mechanical Engineering
This paper experimentally investigated the endwall heat transfer distribution in a rotating rectangular cooling channel (Aspect ratio = 4:1) using a newly developed steady-state liquid crystal thermography. Three Reynolds numbers (5000, 10000 and 20000) were tested, and the highest rotation number was 0.65. The buoyancy parameter ranged from 0 to 1.0 at a fixed density ratio of 0.1. Effect of missing fin (one fin missing) on heat transfer in a staggered pin-fin array was studied. For the stationary case, absence of the fin contributed to an undisturbed wake region from the adjacent upstream fins. Both leading and trailing surfaces produced the asymmetric heat transfer distribution along the spanwise direction because of the channel orientation (150 degrees) and rotation. At the highest rotation number, a highly irregular Nusselt number contour was observed on the missing fin region. This was mainly attributed to the intensified rotation induced secondary flow from the enlarged fin spacing, and the heat transfer enhancement of the missing fin case was 20% higher than the full fin case on the trailing surface.
Effect of nonuniform pin size on heat transfer in a rotating rectangular channel with pin-fin arrays
(2019-12-25)
Hung, Shuo-Cheng
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Huang, Szu-Chi
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Liu, Yao-Hsien
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機械工程學系
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Department of Mechanical Engineering
Internal channels to cool the trailing edges of gas turbine blades were typically installed with pin-fin arrays for higher heat transfer enhancement. In this study, the heat transfer characteristics in a rotating rectangular channel (aspect ratio = 4:1) with differently sized pin-fin arrays were experimentally investigated. Liquid crystal thermography was used to measure heat transfer on the endwall in a staggered pin-fin array at a channel orientation of 135 degrees. The staggered array was composed of four or three pins in a row. Pins of varying diameters were inserted in every row exhibiting four pins; either two or four pins were replaced. The rotation numbers ranged from 0 to 0.33, and the Reynolds numbers ranged from 10,000 to 20,000. The results revealed that flow acceleration, separation, and wake flow contributed to various heat transfer contours. Larger pins contributed to higher local flow velocities through fin spacing and produced higher heat transfer distributions. The effect of rotation improved heat transfer enhancement on both trailing and leading surfaces. The friction factor ratio increased when more large-sized pins were installed in the array.
EXPERIMENTAL INVESTIGATION OF HEAT TRANSFER ON THE INTERNAL TIP WALL IN A ROTATING TWO-PASS RECTANGULAR CHANNEL
(2019-01-01)
Chia, Kai-Chieh
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Huang, Szu-Chi
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Liu, Yao-Hsien
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機械工程學系
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Department of Mechanical Engineering
The current study experimentally studied heat transfer characteristics of the blade tip wall in a rotating internal cooling channel. The aspect ratio of this rectangular channel was 1:4, and the hydraulic diameter was 25.6 mm. Due to the impact of the 180 turn, complex three dimensional flow significantly affected heat transfer on the internal tip surface. The liquid crystal method is used to capture the heat transfer contour on the internal tip surface. In this study, the leading and trailing surfaces of the channel wall were either smooth or roughened with 45 angled ribs. The Reynolds number inside the pressurize two-pass cooling channel ranged from 10,000 to 30,000 at both stationary and rotating conditions. Furthermore, two channel orientations (90 and 135) were tested. The effect of Coriolis force on heat transfer is studied with the rotation number up to 0.53. The tip heat transfer from the smooth channel wall was more sensitive to rotation and the largest heat transfer enhancement as a result of rotation was 68%.
Experimental investigation of the effect of compound protrusion-pin array on heat transfer in an internal rotating cooling channel
(2018-07-25)
Ullal, Ankith
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Hung, Shuo-Cheng
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Huang, Szu-Chi
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Liu, Yao-Hsien
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機械工程學系
An experimental investigation was conducted to study the effect of protrusions and their combination with pins on heat transfer enhancement in a rotating internal passage with an orientation angle of 90 degrees for Reynolds numbers (Re) of 10,000 and 20,000. The trailing surface showed the highest Nusselt number (Nu). The highest and lowest local Nusselt number was at the front and back of the protrusion respectively. A short disturbed wake region was observed behind the protrusion as a result of complex three dimensional flow. Addition of pins in the configuration resulted in an increase of the average Nusselt number, specifically a 35%, 50% and 142% for trailing, static and leading surfaces respectively, compared to protrusions only case for Re of 10,000. On removal of the third column of protrusions, average Nusselt number showed a decrease of 8.25%, 3.1% and 2.3% for trailing, static and leading cases respectively, compared to the protrusion-pin case for Re of 10,000. It also caused elongation of the stagnation and wake flow fields around the fourth column comprising of pins. Pressure drop results indicated that the protrusion only case was the lowest compared to protrusion-pin.
Heat transfer measurement in a rotating cooling channel with staggered and inline pin-fin arrays using liquid crystal and stroboscopy
(2017-12-01)
Huang, Szu-Chi
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Wang, Chen-Chih
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Liu, Yao-Hsien
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機械工程學系
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Department of Mechanical Engineering
Endwall heat transfer in the stationary and rotating cooling channels with pin-fin arrays (inline and staggered pattern) were experimentally measured by wide band liquid crystal. The temperature measurement was performed with the stroboscopic photography to capture the reflected color from the liquid crystal coatings on the rotating object. A detailed calibration was performed to quantify the uncertainties in the liquid crystal measurement from the stroboscope frequency, flash duration, and viewing angle. The Reynolds numbers ranged from 5000 to 20000 and the rotation numbers ranged from 0 to 0.52. This measurement technique provided detailed heat transfer variations caused by the distinct secondary flow patterns from pin-fin and rotation. Results showed that the heat transfer from the staggered array was 25-30% higher than the inline array in the stationery channel. The rotation led to unsymmetrical heat transfer distributions along the spanwise direction. The heat transfer variation caused by rotation was more noticeable for the inline array, and the heat transfer in the rotating channel was more than 50% than that in the stationary channel. (C) 2017 Elsevier Ltd. All rights reserved.
High Rotation Number Effect on Heat Transfer in a Leading Edge Cooling Channel of Gas Turbine Blades With Three Channel Orientations
(2013-12-01)
Huang, Szu-Chi
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Liu, Yao-Hsien
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機械工程學系
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Department of Mechanical Engineering
Heat transfer in a leading edge, triangular-shaped cooling channel with three channel orientations under high rotation numbers is investigated in this study. Continuous ribs and V-shaped ribs (P/e = 9, e/Dh = 0.085), both placed at an angle (alpha = 45 deg) to the mainstream flow, are applied on the leading and trailing surfaces. The Reynolds number range is 15,000-25,000 and the rotation number range is 0-0.65. Effects of high rotation number on heat transfer with three angles of rotation (90 deg, 67.5 deg, and 45 deg) are tested. Results show that heat transfer is influenced by the combined effects of rib and channel orientation. When the rotation number is smaller than 0.4, rotation causes a decrease in the average Nusselt number ratios on the leading surface at a channel orientation of 90 deg. Heat transfer is enhanced gradually on the leading surface when the channel orientation varies from 90 deg to 45 deg for both ribbed cases. The highest heat transfer enhancement due to rotation is found at the highest rotation number of 0.65.
HIGH ROTATION NUMBER EFFECT ON HEAT TRANSFER IN A LEADING EDGE COOLING CHANNEL WITH THREE CHANNEL ORIENTATIONS
(2012)
Huang, Szu-Chi
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Liu, Yao-Hsien
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機械工程學系
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Department of Mechanical Engineering
Heat transfer in a leading edge, triangular shaped cooling channel with three channel orientations under high rotation numbers is experimentally studied. Continuous ribs and V-shaped ribs, both at 45 degrees rib angle of attack, are applied on the leading and trailing surfaces. For each rib case, three channel orientations (90 degrees, 67.5 degrees, and 45 degrees) with respect to the plane of rotation are tested. The rib height to hydraulic diameter ratio (e/D-h) is 0.085 and the rib pitch to height ratio (Pie) is 9. Reynolds numbers are from 15000 to 25000, and the rotation numbers are from 0 to 0.65. Results show that the heat transfer variation is influenced by the combined effects of rib configuration and channel orientation. Effect of channel orientation influences local heat transfer distribution inside this triangular channel, and heat transfer is enhanced gradually on the leading surface when the channel orientation varies from 90 to 45 for both ribbed cases in this study.
INFLUENCES OF THE NON-UNIFORM PIN-FIN ARRAY ON HEAT TRANSFER DISTRIBUTION IN A ROTATING RECTANGULAR CHANNEL
(2018-01-01)
Hung, Shuo-Cheng
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Huang, Szu-Chi
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Liu, Yao-Hsien
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交大名義發表
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National Chiao Tung University
The liquid crystal thermography was used to investigate the heat transfer of non-uniform pin-fin arrays in a rotating rectangular channel (AR = 4:1) at a channel orientation of 135 degrees. The pin-fin array consisted of four and three pins in a staggered arrangement. The different sized pins were inserted at the rows exhibiting four pins, which produced a non-uniform distribution of the pin-fin array. The experiments were operated at Reynolds numbers of 10,000 and 20,000 for both stationary and rotating conditions. The rotation number varied from 0 to 0.33 and the buoyancy parameter ranged from 0 to 0.27. Results indicated that various heat transfer contours were observed as a result of flow separation and vortices caused by non-uniform pins. Compared to the stationary case, rotation increased heat transfer on both trailing and leading surfaces. The pin-fin array consisted of 6 and 9 mm pins produced the highest heat transfer and frictional losses under rotation condition.