In this article, turbulent flow heat transfer in the air gap between rotor and stator of a generator under nonhomogeneous heat flux is studied experimentally. The rotor consists of four symmetrical triangular grooves. The stator surface is smooth and does not include any grooves. The relative heat flux between the rotor and the stator is 1 to 3. Temperature and heat flux are measured locally at...

The search for replacement of commutator and brushes in conventional DC motors by electronic commutator has resulted in a class of Permanent Magnet Brush Less (PMBL) motors. The operation of PMBL motor requires synchronization of coil currents with the instantaneous rotor position. The applied voltages of higher magnitudes must have same zero crossings as that of speed induced back EMF of the r...

In this paper, a modified two-fluid model has been adopted to simulate the process of upward vertical subcooled flow boiling of refrigerant R-113 in a vertical annular channel at low pressure. The modified model considers temperature dependent properties and saturation temperature variation and was validated against a number of published low-pressure subcooled boiling experiments. The results s...

This paper studies the torque production mechanism of dual-stator axial-field flux-switching permanent magnet (DSAFFSPM) machine. Due to double-sided slotting design such topology, more resultant air-gap working harmonics in flux density are responsible for and stator permeance is especially considered investigation. Based on magnetic force (MMF)-permeance model, composition difference demonstr...

Thesis for the degree of Doctor of Science (Technology) to be presented with due permission for public examination and criticism in the auditorium 1382 at Lappeenranta ABSTRACT Asko Parviainen This thesis presents an alternative approach to the analytical design of surface-mounted axial-flux permanent-magnet machines. Emphasis has been placed on the design of axial-flux machines with a one-roto...

in conventional direct torque control (dtc), the stator flux is usually kept constant by controlling the x-axis component of the stator voltage in the stator flux reference frame. the torque is then controlled by the y-axis component of stator voltage. in this scenario, the stator current does not exceed its permissible value. however, in the so-called optimal efficiency mode, the induction mot...

With the increasing demand for high-energy density motors applications such as electric vehicles and aircraft propulsion, axial flux permanent magnet are promising. However, utmost care should be taken when designing an motor with a higher torque because of thermal effects. To enhance reliability overall performance motor, efficient management is important, restricted by maximum temperature. Th...

Introduction. Reduction of cogging torque is the crucial design consideration axial flux brushless DC (BLDC) motor, particularly for low-speed applications. Aim. The slot opening displacement technique presented in this article to reduce BLDC motors suitable electric two-wheeler Methods. Double rotor single stator configuration motor most such vehicular Initially double 250 W, 150 rpm designed ...

Effect of time dependent normal transpiration on the problem of unsteady viscous flow and heat transfer in the vicinity of an axisymmetric stagnation point of an infinite circular cylinder moving simultaneously with time-depended angular and axial velocities and with time-dependent wall temperature or wall heat flux are investigated. The impinging free stream is steady with a strain rate . A re...