Faleh A. Al-Sulaiman

• King Fahd University of Petroleum and Minerals

Fiber reinforced composites are susceptible to low velocity impacts where the apparently non-conspicuous impact damage may result in serious deterioration of mechanical properties of the composite material. Improving this inherent weakness of fiber reinforced composites have thus been a focus of intense research. Hybridization of the fiber reinforc...

In the present study, instrumented drop weight impact tests at different impact energies were performed to investigate the modes and mechanisms of the low velocity impact damage in plain weave woven glass fiber reinforced plastic (GFRP) composite laminates. 8-ply, 16-ply, 24-ply and 32-ply laminates having identical 0 o layup were examined via opti...

Instrumented drop weight impact tests at different impact energies were performed to investigate the effect of ply stacking sequence and thickness in plain weave glass fiber reinforced composite laminates with 0º and 0/90º ply orientations. Post impact tensile tests were performed to predict the residual strength of the material. It was found that...

Sensitivity analysis is a tool employed in engineering problems to identify the influence of input parameters on the state variables such as displacement, stress, strain and temperature. In the case of composite laminates the impact resistance depends on a number of parameters, which have been extensively studied by a number of researchers. But the...

Modal analysis of complex rotor-bearing systems using the finite element method (FEM) may become controversial when considering the tradeoff between geometric complexity and elastodynamic integrity of the FEM model. In this paper, the modal characteristics of an actual multi-impeller rotor-bearing system with complicated geometry are estimated and...

The effect of V-cut at impeller blades' exit on internal pressure fluctuations, case vibration, and performance of a double volute boiler-feed pump has been investigated. Scaled model pump and two impellers, with and without the V-cut, were used in a closed water test loop to conduct experimental testing. The V-cut increases the effective gap betwe...

The effect of V-cut at impeller blades' exit on internal pressure fluctuations, case vibration , and performance of a double volute boiler-feed pump has been investigated. Scaled model pump and two impellers, with and without the V-cut, were used in a closed water test loop to conduct experimental testing. The V-cut increases the effective gap betw...

The sonic tomography and infrared thermograph techniques are incorporated to monitor the orientation and the size of the defect sites in the palm tree trunks. The tests are carried out for various conditions of the palm tree trunks, which have the large defect sites caused by the insects. The sonic tomography technique relies on the measurement of...

Burst tests have been performed on the glass fiber-reinforced (GFR) thermoset pipes before and after exposure to natural and accelerated environmental conditions. The main objective of this study was to explore the effects of long-term natural outdoor and artificial accelerated environmental conditions on the burst resistance of the vinyl-based and...

The lack of reliable engineering data on the durability of glass fiber reinforced Epoxy (GFRE) pipes when exposed to harsh Arabian Gulf outdoor environment has limited their wide use for saltwater and crude oil handling and transportation. This article explores the combined effect of natural and accelerated weathering and seawater on tensile proper...

This paper presents a study of the effects of harsh outdoor weather and warm sea water on the tensile behavior of Glass-Fiber Reinforced Vinylester (GFRV) pipe materials destined for sea water handling and transportation. The effect of Dhahran’s outdoor weather for exposure periods ranging from 3 to 36months revealed an improvement in tensile stren...

Composites are overtaking their traditional counterpart materials by prooving themselves to be superior alternatives even for their application in harsh environmental conditions. The technological innovations and developments in manufacturing processes, which lead to a wide range of new composite products, have made them attractive candidates for a...

In the present study, laser cutting of Kevlar laminate is considered, and the effect of assisting gas pressure and laser output power on the end product quality is examined. The end product quality is judged via measurement of out-of-flatness and kerf width ratios. Experimental tests are carried out using a CO2 laser beam with pulse repetition rate...

The acoustic chamber for the detection of insects provides for the acoustic detection of insects living within the trunk of a tree. The chamber includes an annular shell disposed around the trunk of the tree to define an annular acoustic or sound chamber. Acoustic sensors are mounted in the shell walls. The acoustic sensors may be microphones that...

Experimental investigations of drillstring dynamics are essential to complement the theoretical studies and to alleviate the complexity of such dynamic models. This article presents an experimental investigation using a specially designed drilling test rig. The test rig can simulate the drillstring vibrational response because of various excitation...

The use of glass fiber reinforced Epoxy (GFRE) pipes for seawater and crude oil handling and transportation in Saudi Arabia is hindered by the lack of reliable engineering data on the durability of these pipes when exposed to harsh Arabian Gulf outdoor environment. This paper presents a study of the effects of natural outdoor weather and seawater o...

Drillstring vibration is one of the major causes for a deteriorated drilling perfor-mance, and if left untreated may result in a complete failure of the drilling process. Although the variations in the drilling load, stick-slip, and whirling are known to be the primary causes of severe vibrations, they often give rise to excessive flexural deformat...

Machining of Kevlar laminates with conventional methods results in poor end-product quality and excessive specific energy requirement for machining. However, laser machining has considerable advantages over the conventional methods due to precision and rapid processing. In the present study, laser hole cutting into Kevlar laminates with different t...

Laser cutting of Kevlar plates, consisting of multilayered laminates, with different thicknesses are carried out. A mathematical model is developed to predict the kerf width, thermal efficiency, and specific energy requirements during cutting. Optical microscopy and Scanning Electron Microscopy (SEM) are employed to obtain the micrographs of the cu...

This paper presents preliminary findings of the energy analysis of a cooling system with two-stage evaporative coolers using liquid desiccant dehumidifier between the stages. The proposed evaporative cooling system utilizes air humidity for cooling in humid areas and requires no additional water supply. The major energy requirement associated with...

In the present study laser cutting of composite structure, consisting of Kevlar laminate at the top and mild steel sheet at the bottom, is considered. The end product quality is assessed using the thermal cutting standards. To compare the end product quality of composite structure cuts, Kevlar laminate and mild steel sheet are cut using the same cu...

Drillstring vibration is one of the major causes for a deteriorated drilling performance. Field experience revealed that it is crucial to understand the complex vibrational mechanisms experienced by a drilling system in order to better control its functional operation and improve its performance. Sick–slip oscillations due to contact between the dr...

Field experience manifests that drillstring vibration is one of the major causes for a deteriorated drilling performance. It is crucial to understand the complex vibrational mechanisms experienced by a drilling system in order to better control its functional operation and improve its performance. Experimental studies of drillstring dynamics are es...

Laser cutting of composite structure consisting of 64 layers of plain-weave carbon/carbon fibers with 0° orientation is carried out. The influence of laser power on the kerf size is examined experimentally as well as analytically. The scale law analysis is introduced to predict the kerf width. The striation formation on the kerf edges is examined u...

Three empirical formulas are developed to predict the thermal conductivities of fiber-reinforced composite laminates (FRCL) and its constituents. The inherent two or three-dimensional problem that is common in composites is simplified to a one-dimensional problem. The validity of the models is verified through finite element analysis. This method u...

The need to determine the thermal conductivity of fibers for design purposes of new composite materials and the inherent difficulties in the direct measurement of the thermal conductivity of fibers motivated the present work due to its importance for energy conservation purposes. In this work, a correlation formula is developed to predict the therm...

A universally applicable and reliable method for online monitoring of tool condition is presented. This method is based on monitoring the differential electrical power consumption. In this technique the power for running spindle motor is nullified and only the power required for actual drilling process is recorded. Therefore, unlike other conventio...

There are inherent difficulties in the direct measurement of the thermal conductivity of fibers. The need to determine the thermal conductivity of fibers for design purposes has been the motivation of the present work. Four empirical formulas are developed to predict the thermal conductivities of fiberreinforced composite laminates (FRCLs) and thei...

Drillstring vibration is one of the major causes for a deteriorated drilling performance. Field experience revealed that it is crucial to understand the complex vibrational mechanisms experienced by a drilling system in order to better control its functional operation and improve its performance. Stick-slip oscillations due to contact between the d...

This paper presents preliminary findings of the energy analysis of a cooling system with multistage evaporative coolers using liquid desiccant dehumidifier between the stages. The proposed evaporative cooling system utilizes the air humidity for cooling in humid areas and requires no additional water supply. The major energy requirement associated...

The contact between the drilling bit and formation is known to excite severe torsional and axial vibrations in the drillstring. A dynamic model of the drillstring including both drillpipe and drillcollars is formulated. The equation of motion of the rotating drillstring is derived using Lagrangean approach together with the finite element method. T...

This article addresses the machinability of plain weave Kevlar® 49 prepeg composite laminates of different thickness while using 135° split-point TiN coated 6 mm diameter HSS drills. The effect of composite preparation parameters and the drilling conditions on the machinability of the laminates is assessed using the drilling thrust force, cutting t...

Two empirical models for electrical and mechanical power prediction were developed for drilling mild steel. Multiple linear regression analysis was implemented using a three-level three-variable (3(3)) factorial design experiment for mild steel. The drill diameter, feed rate and cutting speed are the independent variables. Both models were in close...

The corrosion performance of carbon reinforced plain-weave laminates in 3.5% NaCl solution was evaluated by different corrosion measurement techniques to determine the suitability for applications in a corrosive environment. Based on the experimental studies it was observed that this composite offers a high resistance to corrosion in 3.5% NaCl solu...

Several panels of date palm leave (DPL) reinforced composites were fabricated using either autoclaving technique with vacuum bagging or press moulds with controlled temperature. Several fibre orientation and dimensions were tested. Two types of resins were selected. The first was a high temperature curing Phenolic (phenol formaldehyde) resin. The s...

The mechanisms involved in initiation and development of non-ambient temperature fatigue damage in Plain Weave-Woven Carbon fabric/epoxy Composite laminates is explored. Laminates obtained from prepreg woven carbon fabric layers were subjected to tension-tension cyclic loading at –20 o C, 0 o C, 24 o C 100 o C and 150 o C. Two different stacking se...

Mechanical properties of several laminates of date palm leave (DPL) reinforced composites are investigated. Three different processes to construct these composite laminates are assessed. These are wet lay-up with simple vacuum bagging, autoclaving with vacuum bagging and Vulcan press moulding. Several fiber orientation and dimensions are tested. Tw...

A special test setup is designed to evaluate the performance of three natural fibers to be used as wetted pads in evaporative cooling. The chosen fibers are date palm fibers (stem), jute and luffa. As a reference, a widely used commercial wetted pad is chosen. The performance criteria include cooling efficiency, material performance and cooling eff...

The influence of temperature on fatigue resistance of Plain Weave Woven CFRP isexamined. The 8-ply laminateswere obtained from epoxy resin prepreg fabric layers stacked in two different sequences, producing unidirectional [0]8 and angle plied [0, 0, 45, −45]s orientations. The fatigue tests were carried out at −20, 0, 24, 100 and 150°C. It wasfound...

An analytical model, based on stiffness degradation during fatigue loading, which has been used for fatigue life predictions in the Fiber Reinforced Plastics (FRP), is employed to examine its validity to the fatigue life predictions in the Woven Fabric Reinforced Plastics. The rate of stiffness degradation (dE/dN) has been obtained from the constan...

An analytical model, based on stiffness degradation during fatigue loading, which has been used for fatigue life predictions in the Fiber Reinforced Plastics (FRP), is employed to examine its validity to the fatigue life predictions in the Woven Fabric Reinforced Plastics. The rate of stiffness degradation (dE/dN) has been obtained from the constan...

The basic mechanical properties of date palm leaves are investigated. This abundant and cheap fibrous material exhibits very favorable characteristics that can make it an excellent building block in composite structures. The tensile strength (210 MPa) and the specific strength (180 MPa cm³/g) of this fiber are higher than many common building mater...

In this paper the isotropic sky method of Liu and Jordan is used to theoretically estimate the monthly average daily and hourly solar radiation impinging on an unshaded tilted surface in Dhahran, Saudi Arabia. The surface receiving solar radiation is assumed to be fixed at a tilt angle, β, equal to the latitude of Dhahran, Ø and oriented such that...

A survey of residential-energy consumption in the eastern province of Saudi Arabia for the year 1410 A.H. (August 1989–July 1990) has been carried out to provide information concerning residential electrical energy-consumption patterns and to ascertain causes of failures. Monthly energy consumption of 17 randomly selected villas and 63 apartments w...

A simple and auspicious scheme to estimate exergy losses in multi-stage flash (MSF) plants is discribed. This method is used to evaluate major MSF plants in Saudi Arabia, namely, Al-Khobar II, Al-Jubail II, and Shuaibah. This study presents a quantitative assessment of the exergy losses, exergetic efficiency, and exergy-destruction term for each pl...

This paper is intended to report preliminary results in the area of actuator placement in a lumped parameter system subjected to a disturbance at a known location. A criterion has been established relating the optimal actuator position to the location of the disturbance.Linear time invariant lumped parameter models were chosen to investigate the ef...