Secondary Pump Research Articles

Distribution and accumulation of oil and gas in southern Huanghua Depression

Abstract On the basis of oil and gas distribution in southern Huanghua Depression, the hydrocarbon accumulation conditions and developing characteristics of the main faults of different stages are researched. The mechanism of source faults accumulating hydrocarbon is analyzed. Research shows that the seismic pumping mechanism of long-term developing source faults is the main driving force of hydrocarbon accumulation. The sources of seismic pumping control the horizontal distribution of hydrocarbons, while the sources of seismic pumping and the secondary seismic pumping sources produced by the main tensional layer control the lengthways accumulation of oil and gas. The reservoir sands or oil traps near the seismic pumping region may be the most efficient fields for hydrocarbon accumulation. Hydrocarbons sourced from the second member of the Kongdian formation are mainly distributed at the southwest tail of the Kongxi fault and the fault rapidly decreased displacement or the abruptly changed strike of the Kongxi, Fenghuadian, and Kongdong faults. The main tensional layer of the upper Kongyi formation accumulates large quantities of oil and gas.

Application of Innovative Technologies for a Continuous Commissioning Case Study

ABSTRACT This article demonstrates the implementation of innovative technologies during continuous commissioning® (CC) practices to improve building operations and reduce energy costs. A 46-year-old typical commercial building with a floor area of about 216,000 square feet was used as a case study building. The HVAC systems were upgraded and retrofitted in 2000. Variable frequency drives (VFDs) were installed for most of the fans and pumps. This CC project involved very minor HVAC retrofits and control upgrades. The new technologies include the fan airflow station (FAS) technology for building pressure control and supply fan control, and a recently developed pump water flow station for secondary pump control. The results show that these technologies improve building operation/maintenance and significantly reduce energy costs. The monthly average electricity savings for HVAC systems is 64 percent, and the average gas savings is 49 percent.

Improving the universal response of evaporative light scattering detection by mobile phase compensation

Mobile phase compensation, first reported for the charged aerosol detector (CAD), was used as a suitable method to overcome problems related to the mobile phase-dependent response of the evaporative light scattering detector (ELSD). Mobile phase compensation was effectively performed both in the flow injection- and in gradient modes. Without compensation, the response factors of the ELSD for six sulfonamide drugs differed by a factor of two when varying the mobile phase composition between 10 and 90% acetonitrile. This change could be effectively eliminated using the technique of mobile phase compensation, where a secondary pump with a reversed gradient was used to provide the detector with a constant composition of the mobile phase. For identical experimental conditions, the ELSD showed a nearly constant, albeit somewhat reduced, response with compensation. This indicates that under such conditions, the ELSD behaved as a concentration-sensitive detector. The analysis of sulfonamides drugs at 0.05% level using gradient UPLC-ELSD separation with mobile phase compensation is demonstrated.

Control of Coherent Phonon Decay in GaAs by Using a Secondary Pump Pulse

Control of Coherent Phonon Decay in GaAs by Using a Secondary Pump Pulse

Enhancement of multiwavelength generation in the L-band by using a novel Brillouin-Erbium fiber laser with a passive EDF booster section

We demonstrate a novel scheme to generate multiple wavelengths in the L-band using a Brillouin-Erbium fiber laser. Our scheme utilizes extraneous amplified spontaneous emission in the C-band as a secondary pump source for a passive Erbium-doped fiber gain section along the cavity. The Brillouin gain medium is generated by the 6.7 km long of single mode fiber (SMF-28). We experimentally demonstrate that a total of 28 stable output channels with a spacing of 0.089 nm can be generated using our new scheme. This represents a 33% increase in the number of wavelengths generated compared with conventional schemes.

Energy evaluation of optimal control strategies for central VWV chiller systems

Under various conditions, the actual load of the heating, ventilation and air conditioning (HVAC) systems is less than it is originally designed in most operation periods. To save energy and to optimize the controls for chilling systems, the performance of variable water volume (VWV) systems and characteristics of control systems are analyzed, and three strategies are presented and tested based on simulation in this paper. Energy evaluation for the three strategies shows that they can save energy to some extent, and there is potential remained. To minimize the energy consumption of chilling system, the setpoints of controls of supply chilled water temperature and supply head of secondary pump should be optimized simultaneously.

Chronic Venous Insufficiency

Chronic Venous Insufficiency

Wavelength tunable linear cavity cladding pump Er3+/Yb3+co-doped fiber laser operating in L-band

We have demonstrated a novel tunable linear cavity Er3+/Yb3+ co-doped fiber laser, which utilizes amplified spontaneous emission as a secondary pump source so that it can operate in L-band. The tuning wavelength range can be up to 34 nm, from 1588.6 to 1622.6 nm, and the output power excursion of the laser at different wavelengths can be less than 0.4 dB by using a two sections of high-birefringence fiber loop mirror as the wavelength filter. The high output power of 200 mW is realized by using the cladding-pump.

High‐efficiency generation of cladding pumped Erbium‐ytterbium co‐doped double clad fiber ring laser operating in L‐band

AbstractA novel Er3+/Yb3+ co‐doped double‐clad fiber‐ring laser, which utilizes amplified spontaneous emission as a secondary pump source in order to operate in L‐band, is demonstrated. Six laser diodes are used to cladding‐pump Er3+/Yb3+ co‐doped double‐clad fiber. When the pumping power of entering fiber is 2731.8 mW, the maximum output power is 518.4 mW, and the slope efficiency is 19%. The relationship between the output power and the splitting ratio of the output coupler is also studied in this paper. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 43: 213–215, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20422

Optimum Pumping Configuration for<tex>$L$</tex>-Band EDFA Incorporating ASE Pump Source

L-band gain improvement through usage of secondary pumping sources in the form of amplified spontaneous emission (ASE) was conducted. A simulation of the three-level rate equation that precedes the experimental approach provides a limited overview of the behavior of various inputs into the active medium-the erbium-doped fiber. Gain improvement as high as 6 dB was attained while incurring minimal noise figure penalty; in this case as low as 1 dB. For an L-band amplifier system employing ASE to improve gain, pumping the system counterdirectionally with ASE while the 980- or 1480-nm pumps are being used in a copropagating configuration would yield the best overall performance in terms of gain.

Pumping scheme optimisation of 980-nm pumped L-band EDFA associated with broadband noise as the secondary pump

L-band gain improvement through usage of secondary pumping sources in the form of broadband noise (amplified spontaneous emission, ASE) is conducted. For an L-band amplifier system employing ASE to improve gain, pumping the system counter-directionally with ASE while the 980-nm pump is being used in a co-propagating configuration would yield the best overall performance in terms of gain and noise figure. For high power applications, the 980-nm and ASE sources must be counter-directionally pumped to the direction of the L-band signal. Gain improvement of 1570-nm signal in between 6 and 8.5 dB is attained at 12 mW of 980-nm pump laser.

Reflection L‐band erbium‐doped fiber‐amplifier‐based on a fiber‐loop mirror

AbstractA novel reflection L‐band erbium‐doped fiber amplifier, based on a fiber loop mirror, is constructed. This amplifier reflects the backward ASE to the EDF as a secondary pumping source. A gain of 30 dB (an increase of 6 dB) is obtained, compared to the forward‐end‐pumped EDFA in the range of 1570–1603 nm. The saturated output power was 7.63 dBm and 7.6 dBm for 1580 nm and 1600 nm signals, with increases of 2.98 dB and 3 dB, respectively, compared to the forward end‐pumped EDFA. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 36: 501–503, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10803

Double Pass L-Band EDFA with Unpumped EDF

A new double pass long wavelength band erbium-doped fibre amplifier (L-band EDFA) with a further improved gain is demonstrated using double pass technique with a first 5 m of the EDF is unpumped. The wasted conventional band (C-band) backward amplified spontaneous emission (ASE) is used as a secondary pump source for the unpumped EDF. Our experimental results have shown that, compared to a conventional double pass amplifier, the gain coefficient can be improved considerably from 0.24 dB/mW to 0.40 dB/mW. The new amplifier uses only 67% of the pump power to achieve a gain value equal to that for the conventional amplifier. The maximum gain enhancement of 22.5 dB was observed at a signal wavelength of 1568 nm of while signal and pump powers were fixed at -30 dBm and 62 mW, respectively.

Wavelength tunable erbium-doped fiber ring laser operating in L-band

We describe a novel erbium-doped fiber ring laser utilizing the backward amplified spontaneous emission (ASE) power as a secondary pump source so that it can operate in L-band stably. The output wavelength can be tuned in a wide range of 45 nm, from 1560 to 1605 nm. We also compared this scheme with the condition of not using the ASE as secondary pump source, and found this scheme could improve the performance of the laser when using the same components.

Efficient multiwavelength generation of Brillouin/erbium fiber laser at 1600‐nm region

AbstractAn efficient Brillouin/erbium fiber laser, which operates in the 1600‐nm (L‐band) region, is demonstrated for potential applications in future dense‐wavelength division multiplexing communication systems. The laser configuration consists of an L‐band EDFA (to enable L‐band amplification) where two 3‐dB couplers take a portion of the generated BEFL signal and re‐inject it into the single‐mode fiber in order to seed a cascaded BEFL line in the same direction as the first BEFL line. An efficient BEFL can be obtained by recycling backward a 1550‐nm‐band amplified spontaneous emission as a secondary pump source for the unpumped EDF in the L‐band EDFA section. As a result, the lasing threshold is reduced and slope efficiency is improved. A stable and strong laser comb of up to five lines with 10‐GHz spacing has been obtained with a Brillouin pump of 4.8 mW and a 980‐nm pump of 92 mW. © 2002 Wiley Periodicals, Inc. Microwave Opt Technol Lett 35: 506–508, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10650

Variable Water Flow Pumping for Central Chilled Water Systems

A new variable water (VW) flow system for chilled water system application is presented. Design, operational, and control issues are discussed. Analytical models of pump power and evaporative temperature are developed. The VW systems consume considerably less pump and compressor energy than the primary secondary (PS) systems under partial load conditions for most existing chillers. The VW system consumes less compressor energy since it results in higher refrigerant temperature in the evaporator. The VW systems also have the decoupling capability of the primary and secondary pumping systems.

Efficient multiwavelength linear cavity erbium‐doped fiber laser over 1570–1600 nm

AbstractA simple and efficient L‐band multiwavelength linear cavity fiber laser was obtained at room temperature by recycling detrimental 1550‐nm band amplified spontaneous emission as a secondary pump source for the unpumped EDF section of fiber laser. The cavity was formed by two linear fiber loops. By changing the states of PCs inserted to fiber loops, stable dual‐ and tri‐wavelength lasers with about 1‐mW/channel were generated at room temperature. © 2002 Wiley Periodicals, Inc. Microwave Opt Technol Lett 34: 296–299, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10441

Long‐wavelength EDFA gain enhancement through 1550‐nm‐band lasing

AbstractGain enhancement and bandwidth broadening in a long‐wavelength band (L band) EDFA are demonstrated by incorporating an erbium‐doped fiber laser. Utilizing the strong 1550 nm lasing signal used as a secondary pump source, considerable improvements in gain and its bandwidth are achieved. The enhancement of the L‐band gain characteristics is strongly influenced by a secondary pump signal wavelength and its optical power. © 2002 Wiley Periodicals, Inc. Microwave Opt Technol Lett 33: 240–242, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10286

Detection of targets in continuous random media: A numerical study using the angular correlation function

AbstractA three‐dimensional (3D) finite‐difference–time‐domain (FDTD) scheme is used to study the angular correlation function (ACF) of the scattered fields from continuous random media (volume) with and without a target object present. The FDTD simulations are employed to examine the effectiveness of ACF for object detection in the presence of volumetric clutter. It is shown that the frequency‐averaged ACF can be as much as 10‐dB greater when a target object is present for situations where the target is undetectable by direct examination of the radar cross section only. © 2002 Wiley Periodicals, Inc. Microwave Opt Technol Lett 33: 242–247, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10287

A novel ASE self-pumping technique for gain-enhanced L-band erbium-doped fiber amplifiers

A novel method of enhancing gain in long-wavelength-band erbium-doped fiber amplifiers is described using the unwanted amplified spontaneous emission (ASE) self-pumping technique. The unwanted ASE from a first stage amplifier is recycled into a second stage amplifier as a secondary pump. Gain improvements in the vicinity of 0.4 and 1.2 dB are obtained in the wavelength range of 1570–1600 nm. This enables support for higher channels in multiwavelength systems with negligible noise figure penalties.