International Conference on Irrigation Management Transfer, Wuhan, China, 20-24 September 1994. Vol. 1. Draft conference papers.

Irrigation managementDamsLocal managementPrivatizationWater users' associationsCase studiesTube wellsIrrigation designLarge scale systemsPerformanceCost recoveryUser chargesSustainability

International Conference on Irrigation Management Transfer, Wuhan, China, 20-24 September 1994. Vol.3. Draft conference papers.

Irrigation managementIrrigation systemsFarmer participationPrivatizationSocial aspectsFarmers' associationsWater users' associationsTrainingPolicyFarmer participationEconomic aspectsFarmer managed irrigation systemsIrrigation programsRehabilitationWater resource management

International Conference on Irrigation Management Transfer, Wuhan, China, 20-24 September 1994. Vol.2. Draft conference papers.

IndonesiaAustraliaIndiaSri LankaNigeriaVietnamBangladeshDominican RepublicTanzaniaNigerPhilippinesColombiaEgyptUzbekistanPeruNepalMexicoThailandIrrigation managementDamsLocal managementPrivatizationWater users' associationsWater distributionCanal irrigationTube well irrigationSocial aspectsFarmers' associationsLand reformSustainability

INVESTIGATION OF FUNDAMENTAL THERMAL-HYDRAULIC PHENOMENA IN ADVANCED GAS-COOLED REACTORS

INL LDRD funded research was conducted at MIT to experimentally characterize mixed convection heat transfer in gas-cooled fast reactor (GFR) core channels in collaboration with INL personnel. The GFR for Generation IV has generated considerable interest and is under development in the U.S., France, and Japan. One of the key candidates is a block-core configuration first proposed by MIT, has the potential to operate in Deteriorated Turbulent Heat Transfer (DTHT) regime or in the transition between the DTHT and normal forced or laminar convection regime during post-loss-of-coolant accident (LOCA) conditions. This is contrary to most industrial applications where operation is in a well-defined and well-known turbulent forced convection regime. As a result, important new need emerged to develop heat transfer correlations that make possible rigorous and accurate predictions of Decay Heat Removal (DHR) during post LOCA in these regimes. Extensive literature review on these regimes was performed and a number of the available correlations was collected in: (1) forced laminar, (2) forced turbulent, (3) mixed convection laminar, (4) buoyancy driven DTHT and (5) acceleration driven DTHT regimes. Preliminary analysis on the GFR DHR system was performed and using the literature review results and GFR conditions. It confirmed that the GFR block type core has a potential to operate in the DTHT regime. Further, a newly proposed approach proved that gas, liquid and super critical fluids all behave differently in single channel under DTHT regime conditions, thus making it questionable to extrapolate liquid or supercritical fluid data to gas flow heat transfer. Experimental data were collected with three different gases (nitrogen, helium and carbon dioxide) in various heat transfer regimes. Each gas unveiled different physical phenomena. All data basically covered the forced turbulent heat transfer regime, nitrogen data covered the acceleration driven DTHT and buoyancy driven DTHT, helium data covered the mixed convection laminar, acceleration driven DTHT and the laminar to turbulent transition regimes and carbon dioxide data covered the returbulizing buoyancy driven DTHT and non-returbulizing buoyancy induced DTHT. The validity of the data was established using the heat balance and the uncertainty analysis. Based on experimental data, the traditional threshold for the DTHT regime was updated to account for phenomena observed in the facility and a new heat transfer regime map was proposed. Overall, it can be stated that substantial reduction of heat transfer coefficient was observed in DTHT regime, which will have significant impact on the core and DHR design of passive GFR. The data were compared to the large number of existing correlations. None of the mixed convection laminar correlation agreed with the data. The forced turbulent and the DTHT regime, Celeta et al. correlation showed the best fit with the data. However, due to larger ratio of the MIT facility compared to the Celeta et al. facility and the returbuliziation due to the gas characteristics, the correlation sometimes under-predicts the heat transfer coefficient. Also, since Celeta et al. correlation requires the information of the wall temperature to evaluate the heat transfer coefficient, it is difficult to apply this correlation directly for predicting the wall temperature. Three new sets of correlation that cover all heat transfer regimes were developed. The ba

Gas Test Loop Booster Fuel Hydraulic Testing

The Gas Test Loop (GTL) project is for the design of an adaptation to the Advanced Test Reactor (ATR) to create a fast-flux test space where fuels and materials for advanced reactor concepts can undergo irradiation testing. Incident to that design, it was found necessary to make use of special booster fuel to enhance the neutron flux in the reactor lobe in which the Gas Test Loop will be installed. Because the booster fuel is of a different composition and configuration from standard ATR fuel, it is necessary to qualify the booster fuel for use in the ATR. Part of that qualification is the determination that required thermal hydraulic criteria will be met under routine operation and under selected accident scenarios. The Hydraulic Testing task in the GTL project facilitates that determination by measuring flow coefficients (pressure drops) over various regions of the booster fuel over a range of primary coolant flow rates. A high-fidelity model of the NW lobe of the ATR with associated flow baffle, in-pile-tube, and below-core flow channels was designed, constructed and located in the Idaho State University Thermal Fluids Laboratory. A circulation loop was designed and constructed by the university to provide reactor-relevant water flow rates to the test system. Models of the four booster fuel elements required for GTL operation were fabricated from aluminum (no uranium or means of heating) and placed in the flow channel. One of these was instrumented with Pitot tubes to measure flow velocities in the channels between the three booster fuel plates and between the innermost and outermost plates and the side walls of the flow annulus. Flow coefficients in the range of 4 to 6.5 were determined from the measurements made for the upper and middle parts of the booster fuel elements. The flow coefficient for the lower end of the booster fuel and the sub-core flow channel was lower at 2.3

Dynamic inundation simulation of storm water interaction between sewer system and overland flows

Copyright © 2002 Taylor & FrancisThis is the Author's Accepted Manuscript of an article published in the Journal of the Chinese Institute of Engineers (2002), available online at: http://www.tandfonline.com/10.1080/02533839.2002.9670691An improved urban inundation model, coupling a 2D non‐inertia overland flow model with a storm water management model, is adopted to simulate inundation in urban areas. The model computes, not only the overland runoff and the water overflow through manholes where surface runoff exceeds the capacity of storm sewers, but also the bidirectional flow interactions between sewers and overland runoff. The model was verified by a typhoon event in Nov. 2000, which resulted in serious inundation in the Mucha area of Taipei City. The result shows that the present model indeed improves simulation accuracy over the earlier model, and can be used to provide a more reliable flood mitigation design