Design and Output Performance Model of Turbodrill Blade Used in a Slim Borehole
Small-diameter turbodrills have great potential for use in slim boreholes because of their lower cost and higher efficiency when used in geothermal energy and other underground resource applications. Multistage hydraulic components consisting of stators and rotors are key aspects of turbodrills. This study aimed to develop a suitable blade that can be used under high temperature in granite formations. First, prediction models for single- and multi-stage blades were established based on Bernoulli’s Equation. The design requirement of the blade for high-temperature geothermal drilling in granite was proposed. A Φ89 blade was developed based on the dimensionless parameter method and Bezier curve; the parameters of the blade, including its radial size, symotric parameters, and blade profiles, were input into ANASYS and CFX to establish a calculation model of the single-stage blade. The optimization of the blade structure of the small-diameter turbodrill enabled a multistage turbodrill model to be established and the turbodrill’s overall output performance to be predicted. The results demonstrate that the design can meet the turbodrill’s performance requirements and that the multistage model can effectively improve the accuracy of the prediction.
The Application of Using Bezier Curve to Design Turbine Blade
The blade of the turbine is analyzed,the principle and characteristics of the Bezier curve are elaborated,the paper presents a method of using Bezier curve to design turbine blade.It was proved that it's a good and simple way to design turbine blade.Through this way,you can build mathematics model easily.It's certainly had some superiority.
Development and Evaluation of Various Drilling Fluids for Slim Hole Wells
Slim hole drilling has gained wide acceptance, however, it presents a new set of challenges and problems. One such challenge is reducing annular pressure losses (APLs). Due to the reduced annular clearance in slim hole wells, the APL is usually high, translating to a high equivalent circulating density which can lead to fracturing the formation and lost circulation. Fifty-three fluids were evaluated for their APLs using three different wellbore configurations under atmospheric conditions and at 150°F. Each fluid was characterized using the Bingham Plastic and Power Law rheological models. It was observed that the partially hydrolyzed polyacrylamide (PHPA) viscosified brines gave the lowest frictional pressure losses of all fluids tested. However, the xanthan viscosified brines exhibited better carrying capacity due to their high viscosities. As expected, APL gradients were reduced at high temperatures due to reduced viscosities which led to reduced carrying capacities of the fluids.