الفهرس 
CHAPTER 1 INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
This thesis represents a mathematical model for turbulent flow with chemical additives in a pipe developed by predicting of skin friction factor in the form of a modified Prandtl-von Karman equation. The model is based on a two-layer approach where turbulent velocity profiles of the viscous sub-layer and turbulent core with neglecting the buffer layer have been studied in the presence of chemical additives. The model approximates the stress deficit caused by the non-Newtonian viscoelastic rheology of a polymer additive. The verification of the model was done by comparing the results with a published Yang and Dou model. The comparison shows that the agreement between the results of the different models and the model can be used for demonstrating turbulent drag reduction in pipelines on an industrial scale. An application for designing a new crude oil pipeline considering the availability of chemical additives or drag-reducing agents (DRA) is made by using the developed model to achieve the desired requirements with minimum power consumption and minimum initial and running costs. Three different pipeline design scenarios are investigated for lower pipe thickness, smaller pipe diameter, and fewer number of pumps. The availability of introducing DRA into the design phase could allow the installation of a pipeline thickness of (0.250 inches) instead of (0.375 inches) without exceeding the maximum allowable operating pressure (MAOP) of 525 psi by injection 10 ppm at each segment of the five pump stations. This permits the throughput to the extent of the desired design 250,000 bbl/day with a saving of 25 % in pipe material costs and the annual total cost of service is reduced 12.47%, giving a return on investment (ROI) of 16.37 %. The second alternative scenario is investigated using a 20-inch pipe diameter rather than a 24-inch pipe. The maximum allowable operating pressure (MAOP) is 945 psi by injection of 22 ppm at each of the five pump stations. The pipeline was managed to give the desired flow rate of 250,000 bbl/day but through the feasibility study, it was found that this scenario is less economical over the years of operating the pipeline because the annual total cost of service increased by 23.2%, giving a return on investment (ROI) of -12%. In the third alternative, a design is conducted by elongating the distance between the pump stations to 266 km by using three equidistance operating pump stations instead of five, maintaining the desired delivery amount of crude oil and not exceeding the maximum allowable operating pressure (MAOP), which is limited to 788 psi. This is done by injection of 34.7 ppm at each of the three pump stations. The results reveal that, the pipeline can transport the desired flow rate at a lower annual total cost of service of 32.7% saving in cost and power consumption and ROI of 25.8%. Therefore, alternative 3 is the best design solution. The net present value (NPV) method is applied to the different design scenarios for a project with a long life of 20 years and 8% interest extracting that scenarios 1 and 3 NPV are positive (> 0). These scenarios can expect a profit and should consider moving forward with the investment. In particular, scenario 3 has a very high NPV than scenario 1. This means the money earned on the investment is worth more today than the cost. Therefore, it represents a good investment. Scenario 2 reveals negative NPV, which means that it is not recommended. The annual cost of service and tariff costs for each scenario are also investigated. By comparing the three scenarios with the base design service annual cost, scenario-3 is considered the best operating scenario in terms of saving energy and money, which saves 25.6% compared with the base design.