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2.2. Fluid Hydraulics

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2.2.3. Pressure Losses

Task is intended to calculate mud flow parameters and pressure losses using mud properties, flow rate and sections geometry. Calculations are performed by sections and the number of section is not limited. It provides a facility to compute pressure loss in whole the circulating system. To calculate pressure losses in surface equipment it is necessary to create sections with equivalent diameter and length. Equivalent diameter must be defined in OD column (ID column shoud be kept as zero). The same way should use for drill string sections - pipe inner diameter must be defined in OD column (ID column shoud be kept as zero). To calculate pressure loss in annulus define appropriate annular sections using OD column for hole size entry and ID column for pipe outer diameter. To finalize total pressure loss calculation it is required to compute and add pressure loss at bit (see Bit Hydraulics chapter). Five rheological models are available (Bingham, Power Law, Herschel-Bulkley, API, Herschel-Bulkley (weighted avg.))

Input Values
	Mud Weight	Density of Mud
	Flow Rate	Flow Rate provided by Pumps
	Rheological Model	Mathematical model used to describe the flow behavior of mud
	FANN Viscometer Dial Readings	Fann Viscometer Dial Reading at 3, 6, 100, 200, 300, 600 revolutions per minute
	Pipe Outer Diameter (OD)	Use Hole Diameter for Annular Section or Pipe Inner Diameter to calculate inside Drill String
	Pipe Inner Diameter (ID)	Use Pipe Outer Diameter for Annular section or 0.0 to calculate inside Drill String
	Pipe Length	Section length
Results
	Mud Velocity	Velocity of mud inside section
	Mud Critical Velocity	Speed threshold above which the type of flow of the mud changes from laminar to turbulent
	Reynolds Number	Dimensionless number that gives a measure of the ratio of inertial forces to viscous forces
	Flow Type	Type of flow of mud within the section
	Pressure Loss	Amount of pressure loss in all sections