Mamdouh T. Ghannam

Rheological properties of carboxymethyl cellulose

This work is a complete and comprehensive study of the rheological properties of carboxymethyl cellulose (CMC) solutions. The study was carried out using the computer controlled RheoStress RS100 system of Haake. CMC concentration in the test solutions ranged by weight from 1 to 5%. This range was sufficiently wide to reveal the nearly Newtonian behavior at the lower end of concentrations, and the definitely pseudoplastic, thixotropic, and viscoelastic behaviors of CMC solutions at the higher end of concentrations. The scope of the study included measurements of steady-state parameters, transient shear stress response, and yield stress. In addition, the thixotropic, creep recovery, and dynamic responses of solutions with high concentrations were measured.

Stability Behavior of Water-in-Diesel Fuel Emulsion

Abstract The presence of water within diesel fuel in the form of water-in-diesel (W/D) emulsion lowers the pollution level of nitrogen oxides and particulate matter. Emulsion of W/D was prepared by high-speed mixing and gradually adding water into the diesel fuel containing a small amount of emulsified agent. We measured the physical properties of diesel fuel and W/D emulsions with a pycnometer for density, Fann V.G. rotational viscometer (Chandler Engineering, Model 3500, Tulsa, Oklahoma, USA) for viscosity, and a Fisher Surface Tensiomat (Fisher Scientific Co., Model 21, Hampton, New Hampshire, USA) for surface tension. We used a computer image analyzer system to investigate the water droplet fuel interaction and the water droplet distribution within the diesel phase. The results of this study show that the emulsions of 10% and 20% W/D were stabilized for 4 weeks and 10 days, respectively, under the conditions of 0.2% surfactant, 15,000 rpm, and 2 minutes of mixing time. Under the same conditions, the stability period is limited to 5 hours for emulsions with a water concentration higher than 20%. An optimum surfactant concentration of 2% was found for 40% W/D due to the polydispersity behavior of the added surfactant. The water droplet distribution and average diameter were significantly affected by the total number of mixing revolutions. We measured and investigated the physical properties of the stable W/D emulsions in terms of density, surface tension, and viscosity.

Rheological properties of aqueous polyacrylamide/NaCl solutions

A comprehensive study of the rheological properties of aqueous polyacrylamide solutions was carried out. A RheoStress RS100 Haake rheometer was used in the measurements. The concentration of polyacrylamide ranged from 0.25 to 1.0% by weight. This range is sufficiently wide to cover many of the rheological features of polyacrylamide in the lower range of concentration. The study included measurements of steady shear flow parameters, transient shear stress response, yield stress, thixotropic behavior, creep recovery, dynamic responses, and temperature effects in the range 10–50°C.

Flow Enhancement of Medium-Viscosity Crude Oil

Abstract This study investigated the different alternatives to enhance the flowability of crude oil with medium viscosity. These alternatives include the addition of water into crude oil to form water-in-oil emulsion, the addition of light petroleum product, the addition of flow improver, and a preheating technique. Temperature range of 10–50°C, water concentration range of 0–50% by volume, flow improver concentration range of 0–5000 ppm, and kerosene concentration range of 0–50% by volume were investigated in the flowability enhancement study of crude oil with medium viscosity. The flowability enhancement in terms of viscosity reduction was investigated using RheoStress RS100 from Haake. A cone–plate sensor was used with a cone angle of °4, cone diameter of 35 mm, and 0.137-mm gap at the cone tip. The addition of kerosene to crude oil improves the flowability much better than any other investigated technique.

Water-in-Crude Oil Emulsion Stability Investigation

Abstract The water-in-crude oil emulsion has great importance in the oil industry. The stability of water-in-crude oil emulsion is investigated over a wide range of parameters. These parameters are water concentration (10–50%), surfactant concentration (0.1–1%), mixing speed (500–2, 000 rpm), salt concentration (0–5%), polymer concentration (0–1, 000 ppm), and temperature (13–40○C). The physical properties of water-in-crude oil emulsion in terms of density, viscosity, and interfacial tension are measured by Pycnometer, Ostwald viscometer, and spinning drop tensiometer, respectively. The stability of water-in-crude oil emulsion is studied for each case in details. This investigation shows that the presence of the emulsifying agent is necessary for stable emulsion, and stability gradually decreases with water concentration. The presence of 5% NaCl or 1, 000 ppm of Alcoflood polymer provides 100% stable emulsion. Emulsion stability reduces with temperature. Impeller type has a strong effect on the emulsion stability. S-curved blade impeller provides 100% stable emulsion for more than 2 days.

Combustion Study of Stabilized Water-in-Diesel Fuel Emulsion

Abstract An experimental investigation has been carried out to produce a stable diesel/water emulsion fuel and use it in a diesel engine under different operating and design conditions. The emulsion stayed stable for up to 30% water in diesel for up to one week and 20% water in diesel for four weeks. The physical properties of the stable W/D emulsions in terms of density, surface tension, and viscosity were measured and investigated. The effect of surfactant concentration, mixing time, and mixer speed has been studied. A computer image analyzer system was used to investigate the water droplets-fuel interaction and the water droplets distribution within the diesel phase. The stable emulsion has been used in an indirect injection Ricardo E6 research diesel engine, and performance and engine roughness parameters have been measured. The effect of water/diesel ratio, engine speeds, loads, fuel injection angle, and engine compression ratio on combustion maximum pressure, maximum pressure rise rate, brake power output, and brake-specific fuel consumption has been studied. The addition of water in diesel generally affected the engine combustion noise, brake power output, and specific fuel consumption.

Interfacial properties of polyacrylamide solutions

Surface tension of the polyacrylamide solution was measured as a function of the polyacrylamide concentration (0–1000 gm/m3) and temperature (10–60°C). The static contact angles of the polyacrylamide solutions in the range of 0–1000 gm/m3 were reported on the polyvinyl chloride and Teflon substrates. Surface tension, static contact angle, and spreading behavior of the polyacrylamide solutions in the presence of different concentrations of NaCl, CaCl2, and AlCl3 are discussed.

The Effect of Temperature and Mixing on the Density and Viscosity of Jojoba-diesel Fuels

The density and viscosity of several jojoba oil biodiesel–diesel fuel blends (B10, B20, B30, B50, and pure fuels B0 and B100) were measured for almost the first time according to the corresponding ASTM standards. In order to predict these properties, mixing rules are evaluated as a function of the volume fraction of biodiesel in the blend and also to check the validity of the mixing rules. The absolute percentage deviations obtained were low, demonstrating the suitability of the used mixing rules. The jojoba biodiesel and its blends have slightly higher density and viscosity, however, the kinematic viscosity may be lowered significantly by increasing the temperature of the fuel. The current work presented lacking data for the jojoba biodiesel and its blend with diesel. These data are required for further experimentation of the fuel, or for simulation and modeling purposes.

Integration of Teaching and Research with Community Service for Engineering Programs.

Teaching and research are actively linked together, one informing and energizing the other. This strong interaction between the two encourages faculty members to inspire, motivate, energize, stimulate, and promote their students towards the real goals of student education. Due to the need for education process improvements and budget constraints, integration of teaching and research with community service is necessary for the advancement of society. The efforts invested for the engineering education, the scientific research, and the combination of teaching and research with community service are not only essential for industrial development, but are crucial for our life, nature, and to enhance the technological and intellectual level of our society. It is important for the scientific engineering community to address, discuss, and propose new ideas to incorporate this interaction for the advancement of the local community. Accordingly, this study is intended to explore the benefits and challenges associated with incorporating teaching and research into community service while also discussing the establishment of such a mechanism.

Rheological properties of water-in-diesel fuel emulsions

The addition of water dispersed phase into the diesel continuous phase will lead to the formation of water-in-diesel (W/D) emulsion, which significantly reduces the pollution level of NOx and particulate matters in the diesel engines. The study of the rheological properties of stable W/D emulsions is important to understand the flow characteristics of these emulsions. Pure diesel fuel and three samples of W/D emulsions (10%, 20%, and 30% by volume water) were examined. Pure diesel fuel exhibits a Newtonian profile since its viscosity remains constant with the shear rate. All W/D emulsions display higher viscosity than diesel fuel with non-Newtonian flow behaviour of yield pseudoplastic response. The viscosity of the W/D emulsions decreases with the shear rate and water addition. The flow behaviour of pure diesel fuel can be described by the Power law model. The Casson model very sufficiently fits the flow behaviour of different W/D emulsions.