Design, Fabrication and Development of House Hold Utensil Cleaning Machine

This work presents design and fabrication of efficient and economical ultrasonic utensil cleaning machine. Electrical energy is converted into Mechanical energy by transducer. Transducer vibrates with ultrasonic frequency supplied to it by the frequency producer. These vibrations produce cavitation bubbles in the solvent/water. The size of the bubbles is in micron range. The mass of the cavitation bubbles depend on the rate of recurrence of the transducer. These bubbles act as scrubber which scrub the surface of utensil thus removing the soils/dirt stick on it. The size of the bubble is so small it does not cause any damage to the surface of utensil. Higher the frequency, more homogeneous will be the cleaning. Rinsing is provided within the system which will make it more compact. To keep the contaminants away from the cleaned surface, sweep frequency is used. Rotation to the basket is given by the motor. This rotation helps to reduce the cycle time and also dry the surface of utensil by centrifugal action. So when the utensil is removed from the basket it is ready for use. By this technology cycle time will be reduced drastically. Without any human efforts it can clean the dirtiest stains from the oily utensils. All types of utensils can be cleaned whether it is ceramics, glass, copper, wood, aluminum, stainless steel, etc. This cleaning process is more hygienic and can clean more efficiently compared to conventional cleaning.

Preparation of Heat-Sensitivity Proteins from Walnut Meal by Sweep Frequency Ultrasound-Assisted Alkali Extraction

Sweep frequency ultrasound- (SFU-) assisted alkali extraction was conducted to increase the yield and content of heat-sensitive protein of walnut meal under a relatively mild condition. The physicochemical and structural characteristics of the proteins obtained by SFU-assisted alkali extraction and the conventional alkali extraction were compared. It was found that the optimal parameters for the SFU-assisted extraction were the solid-liquid ratio of 1 : 12, pH value of 9, initial temperature of 25°C, ultrasonic frequency of 28 kHz, sweep frequency amplitude of 1.5 kHz, sweep frequency cycle of 100 ms, duty ratio of 77%, and ultrasonic time of 90 min. Under this condition, a vast improvement in the walnut protein yield (34.9%) and the walnut protein content (9.8%) was observed. Such improvement was due to the structural changes of the sonicated protein; e.g., SFU decreased the intermolecular/intramolecular hydrogen bond force of proteins and, therefore, caused more order secondary structures and more loosen microstructures. This helped to improve the thermoplastic and solubility of the heat-sensitivity protein. Thus, SFU treatment could be an effective auxiliary technology in the alkali extraction of heat-sensitivity walnut protein. It might also be a promising technology for the extraction of heat-sensitivity protein from other agricultural by-products.

High-Frequency Modeling of a Three-Winding Power Transformer Using Sweep Frequency Response Analysis

A power transformer is an essential device for stable and reliable power transfer to customers. Therefore, accurate modeling of transformers is required for simulation-based analysis with the model. The paper proposes an efficient and straightforward parameter estimation of power transformers based on sweep frequency response analysis (SFRA) test data. The method first develops a transformer model consisting of repetitive RLC sections and mutual inductances and then aligns the simulated SFRA curve with the measured one by adjusting parameters. Note that this adjustment is based on individual parameter impacts on the SFRA curve. After aligning the two curves, the final transformer model can be obtained. In this paper, actual single-phase, three-winding transformer model parameters were estimated based on field SFRA data, showing that SFRA curves simulated from the estimated model are consistent with the measured data.