Evaluation of Liquid Film Thickness in Gas-Liquid Annular Flow in Horizontal Pipes Using Three Methods
Issue:
Volume 5, Issue 4, July 2020
Pages:
57-65
Received:
4 March 2020
Accepted:
23 March 2020
Published:
3 September 2020
Abstract: Experimental investigations on annular flow film thickness were conducted using a closed-loop horizontal pipe with an internal diameter of 2-inch (0.0504m). The aim is to progress the understanding of such flow and facilitate the optimum design of hydrocarbon production systems were such flow is encountered. Liquid film thickness was extensively investigated using three methods: the conductance probe sensors installed at the bottom of the pipe, conductivity ring sensors and triangular relationship model. From these methods, liquid film thickness was proven to decrease with increase in superficial gas velocity, while increases with increase in superficial liquid velocity. In comparison, the predicted triangular relationship liquid film thickness matched better with the liquid film thickness obtained from conductance probe sensors at all the flow conditions in the experiments, while the conductivity ring sensor results matched closely at superficial liquid velocity of 0.0505m/s and 0.0714m/s but overestimated at superficial liquid velocity of 0.0903m/s and 0.1851m/s. This has shown the impact of high superficial gas velocity on conductivity ring sensors in accounting for liquid film thickness.
Abstract: Experimental investigations on annular flow film thickness were conducted using a closed-loop horizontal pipe with an internal diameter of 2-inch (0.0504m). The aim is to progress the understanding of such flow and facilitate the optimum design of hydrocarbon production systems were such flow is encountered. Liquid film thickness was extensively in...
Show More
Impact of Climate Variability and Its Related Disease Prevalence on the Yield of Winter Wheat (Triticum Aestivum Lam) in South East Ethiopia
Chala Abebe Aredo,
Cherinet Seboka Ambaye
Issue:
Volume 5, Issue 4, July 2020
Pages:
66-74
Received:
6 February 2020
Accepted:
4 March 2020
Published:
7 September 2020
Abstract: Impacts of climate variability and disease prevalence on crop productivity (particularly wheat yield) are becoming major concern on their stable supply that affecting the livelihood of the farmers and consumers in South-East Ethiopia. The study was carried out with general objective to examine the effect of precipitation, temperature variation and disease prevalence on winter wheat (Triticum Aestivum Lam) for the last 20 years in Sinana farm of Oromia Seed Enterprise south east Ethiopia. Temperature and precipitation trends were evaluated using Sen’s slope estimator and Mann-Kendall trend test methods. The Pearson’s correlation coefficient was used to measure the strength of the association between crop yield and climatic variability. Predictor models on productivity status comprising disease prevalence associated to climate variability for 20 years were established. A1°C temperature rise in average seasonal maximum temperature above the optimum brought productivity reduction by 1.17% coefficient of determination R2=0.428. Further, in 1°C temperature rise, the regression analysis of the productivity related to stem rust prevalence was subjected to a positive impact under Tmin, Tmax, RH, and seasonal RF with coefficient of determination R2=0.756. On the other hand, yellow rust prevalence was positively correlated with minimum temperature, maximum temperature and average relative humidity, but it was negatively correlated with average seasonal temperature. The study concluded that the variability of climate elements has been exerting a huge impact on the quality and quantity of winter wheat.
Abstract: Impacts of climate variability and disease prevalence on crop productivity (particularly wheat yield) are becoming major concern on their stable supply that affecting the livelihood of the farmers and consumers in South-East Ethiopia. The study was carried out with general objective to examine the effect of precipitation, temperature variation and ...
Show More
Evaluating the Effects of Commonly Used Agro-Chemicals on the Health Status of A. Mellifera Scutellata in Southern Nations, Nationalities and Peoples' Region, Ethiopia
Dinku Negash,
Abebe Jenberie,
Asaminew Tassew
Issue:
Volume 5, Issue 4, July 2020
Pages:
74-80
Received:
19 August 2020
Accepted:
27 August 2020
Published:
7 September 2020
Abstract: The study was conducted with the objective of to evaluate the potential effects of widely used agro-chemicals on the health status of Apis mellifera scutllata in Sidama zone, Southern Ethiopia. Seven different agro-chemicals (2, 4-D, Agrothoate 40% Malathion 50%, pyriban48%, Diazinon 60%, Macozeb 80% and Pallas 45 OD) were commonly applied on various crops in the study area. The acute toxicity of these agro-chemicals to honeybees was tested via feeding, contact and fumigation. The mortalities caused by individual agro-chemical were compared with positive control Agro-thoate40% (Diamethoate) and negative control (honey solution and water). Acute toxicity analysis in the laboratory indicated that all tested agro-chemicals were found significantly toxic to A.m. scuttlata compared to negative control via feeding. Agrothoate 40%, Malathion50% EC and Dianznon 60% were highly toxic with 100% of experimental bee mortality, less than an hour. All agro-chemicals were statically significant toxic to honeybee when compared (P<0.01) standard insecticides and control group through all exposure rout. Therefore, proper utilization agro-chemicals are important to minimize poisoning of honeybee.
Abstract: The study was conducted with the objective of to evaluate the potential effects of widely used agro-chemicals on the health status of Apis mellifera scutllata in Sidama zone, Southern Ethiopia. Seven different agro-chemicals (2, 4-D, Agrothoate 40% Malathion 50%, pyriban48%, Diazinon 60%, Macozeb 80% and Pallas 45 OD) were commonly applied on vario...
Show More
