Transportation of waxy crude oil confronts many difficulties due to the formation of gel in the production pipelines, which interrupts the steady production with low transportation efficiency and this later requires a higher pumping pressure to resume the flow. However, the current conventional equation is perceived to be over-predicted, mainly due to low attention given for the compressibility effects. Compressibility of the waxy crude oil has been theoretically reported to have significant influence on the restart pressure of the flow start-up or restart. Moreover, there is limited study on compressibility of waxy crude oil induced by the formation of intra-gel voids as a result of thermal shrinkage encountered during static cooling. This study is, therefore, aimed at investigating the compressibility of waxy crude oil gel experimentally. The experiment included the use of flow loop rig to produce gel at different conditions. The pressure pump rig was designed and fabricated for the compressibility tests. Experiments were conducted at different cooling rates and seabed temperatures. It was observed that higher seabed temperature and slower cooling rates contribute to higher compressibility tendencies. The specimen with faster cooling rates is proven to be less compressible.

Posted on: November 2019

Authored: Shaharin Anwar Sulaiman

Recent research on solar irradiance forecasting has attracted considerable attention, as governments worldwide are displaying a keenness to harness green energy. The goal of this study is to build forecasting methods using deep learning (DL) approach to estimate daily solar irradiance in three sites in Kuwait over 12 years (2008-2020). Solar irradiance data are used to extract and understand the symmetrical hidden data pattern and correlations, which are then used to predict future solar irradiance. A DL model based on the attention mechanism applied to bidirectional long short-term memory (BiLSTM) is developed for accurate solar irradiation forecasting. The proposed model is designed for two different conditions (sunny and cloudy days) to ensure greater accuracy in different weather scenarios. Simulation results are presented which depict that the attention based BiLSTM model outperforms the other deep learning networks in the prediction analysis of solar irradiance. The attention based BiLSTM model was able to predict variations in solar irradiance over short intervals in continental climate zones (Kuwait) more efficiently with an RMSE of 4.24 and 20.95 for sunny and cloudy days, respectively.

Posted on: March 2022

Authored: Shaharin Anwar Sulaiman

A flexible protruding surface was employed as the flow disturbance to promote turbulence at the area of interest. An ultrasonic velocity profiler, UVP technique, was used to study the mean and fluctuating flow properties in the near wake of the rigid and flexible protruding surface in a water tunnel. The polymer based, ethylene-vinyl acetate (EVA) with an aspect ratio of AR = 10, 12, 14, 16 was used as the flexible circular cylinder, and submerged in a flow at Re = 4000, 6000 and 8000. The motion of the cylinder altered the fluid flow significantly. As a means to quantify turbulence, the wakes regions and production terms were analyzed. In general, the flexible cylinders show better capability in augmenting the turbulence than the rigid cylinder. The results show that the turbulence production term generated by the flexible cylinder is higher than that of rigid cylinder. The localized maximum shear production values have increased significantly from 131%, 203% and 94% against their rigid counterparts of AR = 16 at the Re = 4000, 6000 and 8000, respectively. The performance of turbulence enhancement depends heavily on the motion of the cylinder. The findings suggest that the turbulence enhancement was due to the oscillation of the flexible cylinder. The results have concluded that the flexible cylinder is a better turbulence generator than the rigid cylinder, thus improving the mixing of fluid through augmented turbulent flow.

Posted on: June 2021

Authored: Shaharin Anwar Sulaiman

The biggest problem that has been faced globally is the extinction of natural resources for production of energy. Industries as well as consumers should devise some ways to generate energy by utilizing limited resources and hence making the system cost effective. The resources of renewable energy and their reserves are sources of survival in modern era. The ever-rising demand of electricity and the trend that has been shifted to electric vehicles require some devices that can be used for energy production, distribution and storage. The focus of this review is to deduce some efficient techniques utilizing the renewable energy resources that can be cost effective, environment friendly and most economical energy producers. This review also discusses the development of hybridized topologies and tenets, control and energy administrative policies, power electronics interface architectures, different methodologies applied in different hybrid energy systems, designing, types and application arenas. The objective was to uncover the evolution of hybrid energy systems by presenting the research that has already been conducted in this domain and to discuss diverse technologies and control mechanisms they have used in their research.

Posted on: December 2021

Authored: Shaharin Anwar Sulaiman

This study is aimed at testing Mechanical earth modeling (MEM) and Sand onset production prediction (SOP) models using well log and core data to estimate the mechanical properties of the rock, in-situ stresses and the critical conditions at which the rock failure may occur. New numerical models were developed to predict the onset of sand production for Well X. The outputs from MEM were coupled with the Mohr Coulomb failure criterion to calculate the critical wellbore pressure of the well and consequently the depth of the rock at which failure may occur. The results showed that at depth of 1061.68-1098.10 m, the calculated critical wellbore pressures were negatives, which reveal low possibility of sand production. However, at a depth of 1098.25-2230.89 m, the calculated critical wellbore pressures were positives. In this depth range, there was high possibility of rock failure. In conclusion, based on the findings, Well X may produce sand at depth deeper than 1100 m. Therefore, mitigation and preventive actions should be planned for Well X to handle and manage the possible sand production from the identified interval.

Posted on: June 2020

Authored: Shaharin Anwar Sulaiman