Electrical submersible pumps (ESPs) dealing with gas-liquid multiphase flow face great challenges in the oil and gas industries. The main problem is caused by the accumulation of air bubbles inside the ESP, which degrade the pump performance ranging from minor to major degradation (surging and gas-locking). Several empirical models have been developed to predict Head and surging mechanisms. However, the feasibility and versatility of these models are still questionable. Therefore, this study focuses on experimental analysis and their comparison with the existing empirical models (developed to predict Head and surging characteristics under two-phase flow conditions) to examine their validity and versatility in predicting the multiphase performance of pumps. The comparison showed that some models agree well with the given test analysis. However, some models either underestimate or overestimate the predicted values because most of these models were established for high inlet pressure, no water but oil and CO2, several impeller and diffusers, different rotational speed, and different pump geometries. Moreover, this study also compares test results with CFD simulations (using Euler-Euler two-fluid model) and shows that the experimental results are consistent and reliable. Furthermore, this study provides a detailed and close insight into the different aspects of empirical models to check whether they can be applied for wider applications or are limited to the type they were developed.

Post-harvest processes, such as transportation and packaging, should be carried out in such a way that less damage is made to the product. Inappropriate transport of fruits causes mechanical damage. Transport vibrations have a great effect on the extent of damage to agricultural products. In this research, the effects of road vibration on the mechanical properties of olive fruit, including fracture force, fracture energy and elasticity modulus were measured through pressure testing by the instrument before and after Vibration and results were checked. The effect of different parameters of vibrations caused by road transport (frequency, acceleration and time) on the mechanical properties of olive was investigated. Experiments were carried out at two levels of 7.5 Hz and 13 Hz, two acceleration levels of 0.3g and 0.7g and two levels of 30 and 60 minutes. The results of the data analysis showed that the effects of vibration frequency, vibration acceleration, vibration duration were significant on the amount of damage during vibration at the 1% level. The factors caused reduction in mechanical properties.

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One of the most important machines in the olive oil extraction line is the horizontal three-phase centrifugal separator machine or Tricanter. The purpose of this paper is to evaluate the machine designed on the basis of Tricanter and to evaluate the quality of extracted olive oil. For this purpose, four different olive cultivars from Gilan Province in Iran were used. In this research the rotational speed of the Tricanter machine was tested at three levels of 2 500, 3 000, and 3 500 rpm and the content of water added to olive paste was used at three levels of 10, 20, and 30% of the paste mass. Peroxide value (PV) and percentage of acidity were measured for oil extracted from all four olive cultivars. The results of the analysis of variance (ANOVA) test showed that rotational speed and the content of added water had an effect on the acidity and PV for all samples of olive cultivars. The measured values showed that the best speed for the Tricanter machine is 3 500 rpm. At this rotational speed, the peroxide and acidity values are lower than the standard values.