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A mechanistic heat transfer correlation is proposed to estimate heat transfer coefficient for non-boiling two-phase flow in horizontal, slightly inclined, and vertical pipes using the analogy between friction factor and heat transfer. Local heat transfer coefficients, pressure drops and flow parameters were measured for air-water flow in a 27.9 mm stainless steel pipe. The heat transfer and pressure drop data were collected by carefully coordinating the gas and liquid superficial Reynolds numbers. The proposed mechanistic correlation is validated by using experimentally measured heat transfer data. Evaluation of the mechanistic correlation with the measured heat transfer data indicated that the analogy between friction factor and heat transfer can be used with reasonable accuracy for heat transfer predictions in non-boiling two-phase pipe flow. Comparison with experimental results showed that the bulk of the data points were predicted within ±30% by the mechanistic model.

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Hydraulic fracturing technology requires securing sufficient water resources to access and unlock the pores of unconventional formations. Therefore, successful treatment depends on the fracture fluids, which mainly consist of water-based fluids with a low percentage (around 1%) of chemical additives. However, the oil and gas industry is among the largest freshwater consumers: three to six million gallons of water per well based on the number of fracturing stages. As a result, traditional water resources from subsurface and surface supplies are getting depleted, and freshwater is becoming more difficult to access with higher costs associated with continued demand. For example, operator companies in West Texas face many challenges, including a recent increase from USD 2 to 8 per barrel of freshwater. Also, the transportation of raw water to fracture sites, such as the Bakken shale play, has an environmental impact, with costs of up to USD 5 per barrel, while costs of water disposal range from USD 9 per barrel. This paper aims to investigate produced water as an alternative water-based fluid to several fracture fluids, such as crosslinked, linear gel, and high viscosity friction reducers (HVFRs) to reduce environmental footprints and economic costs. The workflow of this research started with a comprehensive review of extant publications, reports, and case studies to summarize the application of produced water with fracturing fluids in unconventional shale plays, such as the Bakken (North Dakota), Barnett (Texas), Eagle Ford (Texas), Wolfcamp (Texas), Marcellus (Pennsylvania), and Periman Bain (Texas). The critical review begins with explaining the features of produced water, its challenges, and water management options. Furthermore, the different fracturing fluids in a high TDS environment are described using recent lab fluid characterizations of produced water as 10% to 50% of produced water usage at a temperature range between 70 to 210 deg F. Moreover, 2D and 3D pseudo frac simulations are utilized using real field data from the Middle Bakken Formation to construct reliable models to evaluate the feasibility of reused water in shale plays development. The outcomes show that recycling water with high TDS in a high-temperature environment can create a fracture network and proppant transport when high viscosity friction reducers with surfactant (HVFR-PRS) was used. In addition, the result of this critical review is a powerful tool for predicting the future of hydraulic fracturing technology, which might help operator companies reduce costs and develop unconventional wells successfully for a return on their investment. The opportunities and challenges conclusions of water management are provided a survey of future hydraulic fracturing applications in North American shale plays by offering recommendations of environmental and economic impacts. The general guidelines obtained can promote the sustainability of using hydraulic fracturing treatment to produce more oil and gas from unconventional resources without compromising on environmental issues.

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A general heat transfer correlation for non-boiling gas-liquid two-phase flow with different flow patterns and inclination angles was developed. To verify the correlation, local heat transfer coefficients and flow parameters were measured for air-water flow in a pipe for the horizontal and slightly upward inclined (2°, 5°, and 7°) positions, and all the flow patterns in the entire flow map. The test section was a 27.9 mm stainless steel pipe with a length to diameter ratio of 95. A total of 763 data points were collected for horizontal and slightly upward inclined positions by carefully coordinating the liquid and gas superficial Reynolds number combinations. The heat transfer data were collected under a uniform wall heat flux boundary condition ranging from about 1800 to 10900 W/m2. The superficial Reynolds numbers ranged from about 740 to 26000 for water and from about 560 to 48000 for air. The general heat transfer correlation was validated with the 763 data points that were experimentally collected. The validation confirmed the robustness of the general two-phase heat transfer correlation to adequately predict heat transfer data for various flow patterns and inclination angles. The accuracy of the correlation to correlate the experimental data was further explored by applying various available void fraction correlations. The performance of the correlation when applied with the different void fraction correlations were compared and appropriate recommendations are made.