Therefore it is important that voltages and power flows in an electrical system can be determined for a given set of loading and operating conditions. This is known as the power flow problem. Power flow analysis is used extensively in the planning, design and operation of electrical systems. In power flow analysis, it is normal to assume that the system is balanced and that the network is compo...

Abstract A continuous Galerkin finite element method that allows mixed boundary conditions without the need for Lagrange multipliers or user-defined parameters is developed. coupling of and Raviart-Thomas basis functions are used. The proven to have a Hamiltonian-conserving spatial discretisation symplectic time discretisation. energy residual therefore guaranteed be bounded general problems ex...

The rolling surface for railroad wheels can be a heat source that may have an impact on the performance of the wheel bearing. In this study, experimental data from an electrically-heated railroad wheel set is analyzed by constructing thermal models of the wheel set. A steady finite-element model, a steady-analytical model, and a transient lumped-parameter model are discussed. Model parameters a...

A hybrid design tool combining one-dimensional (1D) lumped parameter model and three-dimensional (3D) computational fluid dynamics (CFD) approach has been developed and applied to industrial inkjet head design for the application of direct writing on printed circuit boards (PCB). Lumped element modeling technique is applied to simplify the composite Inkjet print head system and the calculation ...

Any disruption of the lymphatic system due to trauma or injury can lead to edema. There is no effective cure for lymphedema, partly because predictive knowledge of lymphatic system reactions to interventions is lacking. A well-developed model of the system could greatly improve our understanding of its function. Lymphangions, defined as the vessel segment between two valves, are the individual ...

A new approach for time-domain analysis and design of lumped networks is considered. The lumped elements are modeled by transmission-line sections or stubs and the modeled network is analysed by the transmission-line matrix (TLM) method, which provides an exact solution to the model. Compensafion of errors arising in modeling the network elements is discussed. Sensitivities w.r.t. design variab...

Two models for describing the operation of a magnetic travelling wave accelerator, the transmission line model and the lumped parameter model, are analyzed. For both cases the current distribution and the magnetic field are calculated. It is shown that the transmission line model can be obtained as the limiting case of the lumped parameter model. It is then assumed that a superconducting soleno...

Time-integration for lumped parameter systems obeying implicit Bingham-Kelvin constitutive models is studied. The governing system of equations describing the lumped parameter system is a non-linear differential-algebraic equation and needs to be solved numerically. The response of this system is non-smooth and the kinematic variables can not be written in terms of the dynamic variables, explic...