The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Jian Song - One of the best experts on this subject based on the ideXlab platform.
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performance analysis of a dual loop organic rankine cycle orc system with wet steam expansion for engine waste heat recovery
Applied Energy, 2015Co-Authors: Jian Song, C GuAbstract:A dual-loop organic Rankine cycle (ORC) system is designed to recover the waste heat of a diesel engine. The high-temperature (HT) loop utilizes the heat load of the engine exhaust gas, and the low-temperature (LT) loop uses the heat load of the jacket cooling water and the residual heat of the HT loop sequentially. These two loops are coupled via a shared heat exchanger. Water is selected as the working fluid for the HT loop and wet steam expansion, which can be implemented through screw expanders, is exploited. The dryness fraction of the wet steam at the inlet of the expander can be adjusted to attain a suitable evaporation temperature and provide a better temperature match with the heat source. The working fluid candidates for the LT loop are chosen to be R123, R236fa and R245fa. The influence of the HT loop parameters on the performance of the LT loop is evaluated. The simulation results reveal that under different operating conditions of the HT loop, the pinch point of the LT loop occurs at different locations and therefore, results in different evaporation temperatures and other thermal parameters. The maximum net power output of the dual-loop ORC system reaches 115.1kW, which leads to an increase of 11.6% on the original power output of the diesel engine.
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Parametric analysis of a dual loop Organic Rankine Cycle (ORC) system for engine waste heat recovery
Energy Conversion and Management, 2015Co-Authors: Jian Song, Chun-wei GuAbstract:This paper presents a dual loop Organic Rankine Cycle (ORC) system consisting of a high temperature (HT) loop and a low temperature (LT) loop for engine waste heat recovery. The HT loop recovers the waste heat of the engine exhaust gas, and the LT loop recovers that of the jacket cooling water in addition to the residual heat of the HT loop. The two loops are coupled via a shared heat exchanger, which means that the condenser of the HT loop is the evaporator of the LT loop as well. Cyclohexane, benzene and toluene are selected as the working fluids of the HT loop. Different condensation temperatures of the HT loop are set to maintain the condensation pressure slightly higher than the atmosphere pressure. R123, R236fa and R245fa are chosen for the LT loop. Parametric analysis is conducted to evaluate the influence of the HT loop condensation temperature and the residual heat load on the LT loop. The simulation results reveal that under different condensation conditions of the HT loop, the pinch point of the LT loop appears at different locations, resulting in different evaporation temperatures and other thermal parameters. With cyclohexane for the HT loop and R245fa for the LT loop, the maximum net power output of the dual loop ORC system reaches 111.2 kW. Since the original power output of the engine is 996 kW, the additional power generated by the dual loop ORC system can increase the engine power by 11.2%.
Chun-wei Gu - One of the best experts on this subject based on the ideXlab platform.
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Parametric analysis of a dual loop Organic Rankine Cycle (ORC) system for engine waste heat recovery
Energy Conversion and Management, 2015Co-Authors: Jian Song, Chun-wei GuAbstract:This paper presents a dual loop Organic Rankine Cycle (ORC) system consisting of a high temperature (HT) loop and a low temperature (LT) loop for engine waste heat recovery. The HT loop recovers the waste heat of the engine exhaust gas, and the LT loop recovers that of the jacket cooling water in addition to the residual heat of the HT loop. The two loops are coupled via a shared heat exchanger, which means that the condenser of the HT loop is the evaporator of the LT loop as well. Cyclohexane, benzene and toluene are selected as the working fluids of the HT loop. Different condensation temperatures of the HT loop are set to maintain the condensation pressure slightly higher than the atmosphere pressure. R123, R236fa and R245fa are chosen for the LT loop. Parametric analysis is conducted to evaluate the influence of the HT loop condensation temperature and the residual heat load on the LT loop. The simulation results reveal that under different condensation conditions of the HT loop, the pinch point of the LT loop appears at different locations, resulting in different evaporation temperatures and other thermal parameters. With cyclohexane for the HT loop and R245fa for the LT loop, the maximum net power output of the dual loop ORC system reaches 111.2 kW. Since the original power output of the engine is 996 kW, the additional power generated by the dual loop ORC system can increase the engine power by 11.2%.
C Gu - One of the best experts on this subject based on the ideXlab platform.
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performance analysis of a dual loop organic rankine cycle orc system with wet steam expansion for engine waste heat recovery
Applied Energy, 2015Co-Authors: Jian Song, C GuAbstract:A dual-loop organic Rankine cycle (ORC) system is designed to recover the waste heat of a diesel engine. The high-temperature (HT) loop utilizes the heat load of the engine exhaust gas, and the low-temperature (LT) loop uses the heat load of the jacket cooling water and the residual heat of the HT loop sequentially. These two loops are coupled via a shared heat exchanger. Water is selected as the working fluid for the HT loop and wet steam expansion, which can be implemented through screw expanders, is exploited. The dryness fraction of the wet steam at the inlet of the expander can be adjusted to attain a suitable evaporation temperature and provide a better temperature match with the heat source. The working fluid candidates for the LT loop are chosen to be R123, R236fa and R245fa. The influence of the HT loop parameters on the performance of the LT loop is evaluated. The simulation results reveal that under different operating conditions of the HT loop, the pinch point of the LT loop occurs at different locations and therefore, results in different evaporation temperatures and other thermal parameters. The maximum net power output of the dual-loop ORC system reaches 115.1kW, which leads to an increase of 11.6% on the original power output of the diesel engine.
Shen-iuan Liu - One of the best experts on this subject based on the ideXlab platform.
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A Bang Bang Phase-Locked Loop Using Automatic Loop Gain Control and Loop Latency Reduction Techniques
IEEE Journal of Solid-State Circuits, 2016Co-Authors: Ting-kuei Kuan, Shen-iuan LiuAbstract:This paper presents a digital bang–bang phase-locked loop (DBPLL) that employs automatic loop gain control and loop latency reduction techniques to enhance the jitter performance. Due to noise filtering properties, a DBPLL has an optimal loop gain which gives rise to the best jitter performance, taking into account external and internal noise sources. By using the automatic loop gain control technique, the DBPLL can automatically attain this loop gain in background to minimize the jitter. This paper also exploits time-series analysis to analyze the DBPLL. In particular, the closed-form gain of a bang–bang phase detector (BBPD) is first derived, taking into account reference clock noise and oscillator noise simultaneously. The chip was fabricated in a 40 nm CMOS process. This DBPLL achieves $ fs integrated rms jitter and $ dBc reference spurs. It consumes 3.8 mW from a 1.1 V supply while operating at 3.96 GHz. This translates to an figure-of-merit (FOM) of $- 245$ dB.
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a digital bang bang phase locked loop with automatic loop gain control and loop latency reduction
Symposium on VLSI Circuits, 2015Co-Authors: Ting-kuei Kuan, Shen-iuan LiuAbstract:This paper presents a digital bang-bang phase-locked loop that employs automatic loop gain control and loop latency reduction techniques to enhance the jitter performance. The chip is fabricated in a 40nm CMOS process. This bang-bang phase-locked loop achieves 290fs rms integrated jitter and reference spurs <-72.89dBc. It consumes 3.8mW from a 1.1V supply while operating at 3.96GHz. This translates to an FOM of −245dB.
Taohong Huang - One of the best experts on this subject based on the ideXlab platform.
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a novel two dimensional liquid chromatography mass spectrometry method for direct drug impurity identification from hplc eluent containing ion pairing reagent in mobile phases
Analytica Chimica Acta, 2019Co-Authors: Zhen Long, Zhaoqi Zhan, Zhimou Guo, Jinting Yao, Xin Zheng, Biao Ren, Taohong HuangAbstract:Abstract In this study, a novel two dimensional liquid chromatography – mass spectrometry (2D-LC-MS) method with use of a weak anion exchange column between the 1st DLC RP column and the 2nd DLC RP column (RP1-WAX-RP2) was developed and applied to identify drug impurities from MS incompatible mobile phases containing sodium 1-octanesulfonate and non-volatile buffer. The 1st DLC conditions follow exactly the original standard HPLC method recorded in Chinese Pharmacopeia (ChP), European Pharmacopeia (EP) or US Pharmacopeia (USP). An impurity fraction was collected with a built-in sample loop (100 μL) and transferred to the WAX column where 1-octanesulfonate and phosphate were trapped and removed. While, the impurity and other cations were eluted to the 2nd D column (RP2) for separation and identification by connected IT-TOF MS. Methods were programmed and applied to identify impurities in two generic drugs, sulpiride (hydrophilic drug with logP 0.57) and dobutamine (hydrophobic drug with logP 3.6). The results indicate that the methods based on RP1-WAX-RP2 column configuration offer a feasible solution for direct impurity identification in generic drug product or API without needs of off-line desalting from the MS incompatible mobile phases containing ion-pairing reagent and non-volatile buffer.
