Dr. Monika IvantysynovaMAHA Professor Fluid Power SystemsDesign and Modeling of Fluid Power SystemsME 597/ABE 591 - Lecture 3MAHA Fluid Power Research CenterPurdue UniversitySICFP’05, June 1-3, 2005, Linköping © Dr. Monika IvantysynovaDesign and Modeling of Fluid PowerSystems, ME 597/ABE 5912Contents1. Introduction and overview of components, circuit and system design methods 2. Fluid properties, types of fluids, cavitation 4. Displacement machines design principles, flow and pressure pulsation5. Steady state characteristics, measurement methods and modeling6. Gap flow models3. Modeling of transmission lines, impedance model of lines, accumulatorsSICFP’05, June 1-3, 2005, Linköping © Dr. Monika IvantysynovaDesign and Modeling of Fluid PowerSystems, ME 597/ABE 5913Modeling of transmissionlinesPurpose of the modelPressure loss (type of flow)Transient pressure, p=f (time)Length lp2Ap1FΔV= s·AsLumped parameter versus distributed parameterFluid inertiaEMSICFP’05, June 1-3, 2005, Linköping © Dr. Monika IvantysynovaDesign and Modeling of Fluid PowerSystems, ME 597/ABE 5914Flow resistance coefficient (friction factor)  = f(Re)@ high Re dependent on surface roughnessfor hydraulically smooth pipesJ.Nikuradse (Moody diagram)laminarturbulenttransientFlow resistance coeff. λReynolds number RePressure lossSICFP’05, June 1-3, 2005, Linköping © Dr. Monika IvantysynovaDesign and Modeling of Fluid PowerSystems, ME 597/ABE 5917Advantage:Maintain fluidpressure constantHydraulic