A method of tensile testing of materials in dynamic conditions based on a slightly modified compressive split Hopkinson bar system using a shoulder is described in this paper. The main goal was to solve, with the use of numerical modelling, the problem of wave disturbance resulting from application of a shoulder, as well as the problem of selecting a specimen geometry that enables to study the phenomenon of high strain-rate failure in tension. It is shown that, in order to prevent any interference of disturbance with the required strain signals at a given recording moment, the positions of the strain gages on the bars have to be correctly chosen for a given experimental setup. Besides, it is demonstrated that - on the basis of simplified numerical analysis - an appropriate gage length and diameter of a material specimen for failure testing in tension can be estimated.
Effects of infrared power output and sample mass on drying behaviour, colour parameters, ascorbic acid degradation, rehydration characteristics and some sensory scores of spinach leaves were investigated. Within both of the range of the infrared power outputs, 300–500 W, and sample amounts, 15–60 g, moisture content of the leaves was reduced from 6.0 to 0.1±(0.01) kg water/kg dry base value. It was recorded that drying times of the spinach leaves varied between 3.5–10 min for constant sample amount, and 4–16.5 min for constant power output. Experimental drying data obtained were successfully investigated by using artificial neural network methodology. Some changes were recorded in the quality parameters of the dried leaves, and acceptable sensory scores for the dried leaves were observed in all of the experimental conditions.
The pole phase modulation (PPM) technique is an effective method to extend speed range and torque capabilities for an integrated starter and hybrid electric vehicles applications. In this paper, the five pole-phase combination types of a multiphase induction motor (IM) with 36 stator slots and 36 stator conductors are presented and compared quantitatively by using the time-stepping finite element method (TS-FEM). The 36 stator conductors of the proposed multiphase IM are fed by a 36 leg inverter and the current phase angle and amplitude of each stator conductor can be controlled independently. This paper focuses on the winding connection, the PPM technique and the performance comparative analysis of each pole-phase combination types of the proposed multiphase IM. The flux distribution, air-gap flux density, output torque, core losses and efficiency of five pole-phase combination types have been investigated.