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Cavitation, a physical phenomenon that detrimentally affects pump performance and reduces pump life, can cause wear on pump elements. Various engineering methods have been developed to identify the initiation and full development of the cavitation process. One such method is the determination of the net positive suction head (NPSH) through a 3% decrease in total head (Hm) at a constant flow rate. In radial pumps, commonly used in agricultural irrigation and industry, cavitation conditions result in a sudden drop in the Hm-Q curve, making it challenging to detect the 3% Hm value drop. This study differs from others in the literature by modelling NPSH, noise, and vibration levels using three machine learning models, specifically artificial neural networks (ANN), support vector machines (SVM), and decision tree regression (DTR). The best-performing model predicts NPSH, noise, and vibration levels corresponding to a 3% decrease in Hm level. The present study determined the NPSH values of a horizontal shaft centrifugal pump at different flow rates and constant operating speed, and the vibration and noise levels were measured for these NPSH values. For each of the NPSH, noise, and vibration levels, ANN, SVM and DTR models were created. The performances of these models were evaluated using criteria such as root mean squared error (RMSE), Mean Absolute Error (MAE) and mean absolute percentage error (MAPE). In addition, Taylor and error box diagrams were created. The ANN model and DTR yielded high accuracy predictions for NPSH values (R² = 0.86 and R² = 0.8, respectively). The ANN model provided the best prediction performance for noise and vibration levels. By entering the level of 3% drop in the Hm value of the pump as external data input to the ANN model, NPSH3, noise, and vibration levels were determined. The ANN models can be effectively employed to determine NPSH3, noise, and vibration levels, particularly in radial flow pumps, where detecting 3% reductions in manometric height value is challenging. [ABSTRACT FROM AUTHOR]

The number of units in the agricultural trailer and tractor park is increasing day by day. The benches, tools and machines used in the manufacturing processes of these units accelerate the production process in terms of quality and quantity in parallel with the developing technologies. However, this intensive production processes can create vulnerabilities in terms of employee health and work safety. In this study, it is aimed to examine and evaluate the agricultural trailer manufacturing process and some environmental conditions in a case workplace. In accordance with this purpose, benches and machines used in agricultural trailer production at Çanakkale were investigated. Noise and lighting levels during the operation of these machines and benches were determined in a sample workplace. In addition, evaluations were made in order to reduce the effects of the obtained noise and lighting on the employees. When the noise measurement results obtained for machines LAeq (the level of sound pressure) values were in the range of 61.74-93.33 dB(A), Lmax (the level of measured sound pressure) values were in the range of 79.53-94.3 dB(A), and LEX (exposure level) values were in the range of 47.38-80.02 dB(A). Considering the results of the study and the noise regulation, suggestions were made to reduce the effects of noise on workers. Suggestions were presented to protect them from these physical, physiological and psychological effects and to increase their working efficiency. When the measurement data results for the machines were analyzed, it was specified that the maximal illumination value which was found in the hydraulic press machine with 951 lux at Measurement 1 before noon and 1082 lux at Measurement 2 in the afternoon. It was specified that the minimal value illumination was the gas welding machine with 107 lux at Measurement 1 before noon and the lathe with 54.4 lux at Measurement 2 in the afternoon. Based on the information determined within the scope of the study, suggestions were also presented for lighting, luminaire selection, lighting calculation and lighting conditions. [ABSTRACT FROM AUTHOR]

In Turkey, some studies have been conducted about already to determining the noise levels of the outdoor agricultural machinery/equipments and some possible measures to betaken have been suggested. In this study, the noise levels of the mixer, selector and hammer drilling machine for feeds which are the post-harvest agricultural machinery used indoors paces have been determined, and their noise maps have been prepared. It was determined that a hammer drilling machine for feeds with 98 dB( A) noise level was over the limit values of the national and international standards, and the possible measures to be taken were discussed. Since the noise levels of the mixer and selector were lower than the value being allowed by national and international standards, it was determined thatthere was no need to make a noise control study. [ABSTRACT FROM AUTHOR]