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The exponential population growth has led to severe fresh water availability issues around the world. Saudi Arabia is one of the countries that mostly rely on desalination process to satisfy their fresh water needs in desert regions. The distillation process has become too expensive due to the sharp rise in oil prices. Renewable energy is a promising source for the water distillation process. This work aims to design, fabricate, and test a solar still for purification of salty and brackish water. A semi-cylindrical solar still was designed and tested under Medina climatic conditions. The semi-cylindrical solar still connected with a parabolic trough solar concentrator was supposed to enhance the system performance and the system productivity by warming up the brackish or saltwater before it was directed to the basin. To calculate system efficiency, the temperatures of water in the basin, glass outside and inside surface, inside of the still, and the ambient were measured. It was found that the average intensity of solar radiation was about $$729.8 \mathrm{W}/{\mathrm{m}}^{2}$$ per hour and the average system efficiency was found to be 23.38% without a parabolic trough. The system efficiency reached 29.5% by connecting the solar still with a parabolic trough. The maximum productivity of the solar still was found to be 1.8 L/h at peak time, with an average value of 0.9 L/h in May.

This study aims to assess the potential of wind energy in Medina by using Weibull probability distribution to provide an insight concerning the energy production from the selected wind turbine Aventa AV-7. Scale factors c and shape k of Weibull distribution, were determined for wind speed frequency. Significant findings included a wind speed recurrence of 2.9 m/s with a probability of 30% approximately. The average c and k were found to be 3.467 and 2.923 m/s, respectively. The estimated average k is relatively high, which indicates that the spread in wind speeds is small. Aventa AV-7 turbine was chosen to test the power generation of wind in Medina. It was found that this wind turbine can generate 8648 kWh/year in the Medina region, which is only 15.2% of the maximum power production. This turbine is expected to generate the maximum possible power output at a wind speed of 7 m/s.

Heat exchanger is a device used to accomplish the transfer of heat from one fluid to another. There are a wide variety of applications regarding shell and tube heat exchangers in the fields of petroleum and industrial applications, due to its enhanced heat transfer characteristics. This project was designed to establish an insight of detailed design and performance of the shell and tube heat exchanger based on energy and mass conservation laws. Solar water heating system techniques were used to provide the system with necessary hot water. One of these techniques was to evacuate tube solar heating system which can be considered as a more efficient way to supply this system with hot water. To enhance the system performance, proper material selection for shell and tubes structure and flow pipe network based on their availability in the local markets was brought into consideration as well. Furthermore, the implemented design was examined under Medina climatic conditions for its cost-effectiveness, simplicity, execution and sustainability. It was found that the heat exchanger efficacy, performance and the vacuum tube efficiency were in highly acceptable ranges and cost effective. In addition, the vacuum tube solar water heating was found to be a clean and safe source of renewable energy. Finally, a comprehensive analysis of the system effectiveness was conducted and the outlet temperature determined for the system varied between 44 to 50ºC for the heat exchanger whereas the vacuum tube exit temperature was elevated up to 84 to 90ºC. The efficiency of the solar collector was found to be 61.84%.

In this work, a survey is used to investigate the current energy performance for Faculty of Applied Medical Sciences (previously Faculty of Engineering) at Taibah University in Medina city. The results of the survey show that several factors affect the energy performance in this building. It revealed that the building has been poorly designed from the point of view of thermal performance. Therefore, the building energy consumption needs to be monitored and maintained through energy auditing program. To determine the energy profile, the power consumption was calculated; the cooling load was estimated and analyzed to know the actual capacity required. The level of comfort in the building has been evaluated. Against the installed air conditioning capacity of 200-ton refrigeration, the cooling load calculations showed that the maximum cooling load needed, which is in August is only 83.22-ton refrigeration. In addition, illumination levels were measured and compared to the standard levels. Based on obtained results, two solutions were proposed: to install a building management system with approximate cost of 337,904 SR and to replace the existing chiller. Finally, the payback period for the proposed system has been estimated and found to be about 5.4 years.

The flow of nanofluids is very important in industrial refrigeration systems. The operation of nuclear reactors and the cooling of the entire installation to improve safety and economics are entirely dependent on the application of nanofluids in water. Therefore, a model of Maxwell’s dusty nanofluid with temperature-dependent viscosity, surface suction and variable surface tension under the action of solar radiation is established. The basic equations of momentum and temperature of the dust and liquid phases are solved numerically using the MATLAB bvp4c scheme. In the current evaluation, taking into account variable surface tension and varying viscosity, the effect of dust particles is studied by immersing dust particles in a nanofluid. Qualitative and quantitative discussions are provided to focus on the effect of physical parameters on mass and heat transfer. The propagation results show that this mixing effect can significantly increase the thermal conductivity of nanofluids. With small changes in the surface tension parameters, a stronger drop in the temperature distribution is observed. The suction can significantly reduce the temperature distribution of the liquid and dust phases. The stretchability of the sheet is more conducive to temperature rise. The tables are used to explain how physical parameters affect the Nusselt number and mass transfer. The increased interaction of the liquid with nanoparticles or dust particles is intended to improve the Nusselt number. This model contains features that have not been previously studied, which stimulates demand for this model among all walks of life now and in the future.

In this study, performance assessment of absorption refrigeration cycle has been carried out under variable power sources namely electric, conventional fuel and renewable energy sources. The ammonia-water absorption cycle was used in this work, the temperatures at each point in the cycle such as generator, absorber, evaporator and condenser have been measured and with using absorption device system. The coefficient of performance and efficiency of the plant were measured and then compared. The results showed that when the cycle driven by electricity, the coefficient of performance varied 0.694 to 1.032 along the test time and the generator temperature changes from 48.1°C to 101.5°C with the average efficiency of 57.1% and average coefficient of performance of 0.78. When methane used as a fuel to generate power the coefficient of performance varied between 0.686 and 0.94 under the generator temperature of 123.3°C and 127.4°C and average efficiency of 40.02% with coefficient of performance of 0.735. Solar energy used as the alternative source of power which is the clean and safe power source and when the plant driven by the solar thermal energy, the coefficient of performance reached to 0.801 under the generator temperature of 91°C, but the system efficiency about 11.68% along the test time. Solar energy can be used efficiently and replaced the conventional power sources to drive the absorption refrigeration unit.

This investigation is conducted to examine potential opportunities of energy savings in the meat processing industry. It demonstrates that energy saving can be considered as a major factor to increase profit and competition within this sector. Detailed energy audits were carried out for meat processing equipment in the national factory. This work shows that there are large opportunities of savings which can be achieved by installing the economiser; using compressed air leakage points in the distribution air network, increasing the suction temperature of the high stage compressors as well as recovering of heat in blow down by preheating feed water which will save even more energy. It was found that the refrigeration systems consume more electricity compared to other departments. However, modification of the water pumping system will save an extra amount of energy. Finally, valuable recommendations to factory management are proposed and required additional research, analysis, and data collection are identified.

The present study documents noise pollution levels measured for the most common cars used by people in Saudi Arabia. The noise levels were measured following standard procedure by using calibrated sound pressure level meter at all sides of the car front, rear, right and left sides. This investigation has been conducted to measure the noise pollution level from Toyota car Model 2002 because it used for most Saudi people. Measurements of the noise level from this car at stationary and motion situation have been carried out. The noise levels produced by variable engine speed ranged from750 to 4000 rpm were recorded. The sound level found to be 59.45 dBA when the vehicle in motion at normal speed. When the vehicle at idle speed 750 rpm the maximum noise level measured at the back exhaust 50.4 dBA where the minimum level recorded at the right side 40.8dBA. When the car parked or at stationary state and the engine at 2500 rpm the maximum noise level at the back exhaust is 53 dB A whereas the minimum level showed from the left side. For maximum engine speed 4000 rpm the back exhaust area has a maximum noise level58.2 dBA where as the right side at 51.2 dBA. The maximum sound level recorded near the engine at speed of 4000 rpm was 57 dBA but the minimum level recorded at 1000 rpm. From the recorded results it can be seen these measured noise level are under the acceptable ranges due to the progress and development of vehicles emission reduction and the environment protection issues. Based on the study findings it can be inferred that there is an urgent need to set up noise standards in the country to control the noise pollution level from vehicles as well as to keep clean environment.

In this investigation, waste polystyrene boxes were collected and treated before mixed with common concrete in especial dies to produce new brick called poly-brick. The main tests performed these tests include the measurement of thermal conductivity, overall heat transfer coefficient and the compression stress. It can be seen that the thermal conductivity of the poly-brick increased with increasing the percentage of waste polystyrene and vary from 0.78 (W/mk) at 0% Polystyrene to 0.227 (W/mk) at 50% and the overall heat transfer coefficient reduced from 7.85 to 2.77 W/m2k. Comparisons between common building structure versus the new Poly-Brick was made and it indicates that the heat transfer rate reduced from 1413 to 498.6 Watt at 50% ratio of the mixture which means 64.7% of energy saving. On the other hand, the compression stress found to be less than that for the common brick. Reduction in energy consumption, which means that low cost of heating and cooling needs, safer, clean and comfortable environment achieved. It is also leads to getting rid of the waste material and has resolved numerous design challenges such as mould.

Energy generation has seen significant development in recent years. This investigation describes a new technique for generating energy from the waste kinetic energy of the vehicles at low speed. A complete description of the system is presented including the general concept, configurations, mechanical design, and electrical system. The system based on the principle of drum rotation due to low movement or transportation of the vehicles driven at low speed at different places such as moles, hotels, universities entrance and fast meals gates. The results show that this new technology could provide an efficient and low cost method of generating electricity from vehicles and the generated electricity has been utilized for different types of applications and mainly for street lighting, domestic uses such as air conditioning, lighting, heating. Some major factors have been studied and practically designed and tested such as there is no possibility to failure or yielding of shaft under loading and the drum is more strength to bending and other forms of stress. It was found through this work that the generated electricity of system and under Jordanian climate conditions can be utilized for electrical and the vehicles waste kinetic energy is one of the renewable sources of energy which can be harnessed to generate electricity. This system depends on the vehicle’s weight, when the weight increase the rpm of the drum will increase. As the horizontal vehicle speed is increased the rotational speed of the drum will be increased. It was found that the effective rotational drum speed (n = 35 rpm) at which the system starts to charging. The friction between the tire and the drum increases when the vehicle weight increases. The reported results indicated that we need only about 10% of vehicle attractive effort to generating a sizable amount of electrical energy. Also, the testing results proven that the minimum effective vehicle’s speed is 20 Km/hr, this means that all of the vehicle going over the system can be harnesses to produce the energy. The suggested model will be able to generate energy may be economically feasible to use for a larger applications, and thus helps to reduce the costs of energy production. On the practical side we have been able to produce and store electrical energy using this model at minimum speed of 20 km/hr, and the system is considered simple to install, inexpensive compared with other sources, safe, and has no bad impacts on the environment. Also, the system can be modified and subjected to upgrading. The system total cost was found to be about US $900 and this is an extra motivation to use this system.

The utilization of renewable energy resources such as wind energy has increased recently due to the rising concern regarding global warming and the associated impact upon climate change, the increasingly rapid depletion of fossil fuel resources and the desire to maximize security of fuel supply. This study deals with autonomous wind pump applications for remote areas in Jordan. The performance of roto-dynamic wind-driven pumps under normal operating conditions has been estimated based on the mathematical model proposed by Mathew and Pandey for the integrated output of wind-driven roto-dynamic pumps. The effects of the specific speed and specific diameter ratios and the gear ratio on the size of the pump selected have been investigated. Specifications and the performance of piston pumps have also been investigated under the same conditions for comparison purposes. It is clear that the roto-dynamic wind-driven pumps offer better performance than the piston pumps.

Water from cooling towers is transported to condensers via a system including screens that are to arrest mechanical impurities and not let them pass into condensate pumps. These screens, when clogged, often cause throttling the water flowing to condensers, hence, interference in power unit operation. Thus, it is of importance to allow for the screen clogging extent monitoring from the power unit control room in order to adapt periodical cleaning frequency to the actual needs. The authors who provided solution to this problem have used an original answer allowing one to observe the system in operation and flow conditions of water stream from cooling towers to condensers and also permitting possible decision taking about cleaning the screens installed in the system [1, 2].

In this investigation; analysis and design of an automobile air conditioner was made by utilizing the available diesel engine exhaust waste energy to provide the required heat for the generator. Because automotive air conditioning is one of the most equipment that heavily uses CFC compounds, and the leakage of CFCs from such air conditioners affect the environment, the absorption cycle was found to be an ideal option. Cooling load for the automobile has been estimated and found to be within acceptable ranges which are about 1.37 TR. The reported results show that the COP values directly proportional with increasing generator and evaporator temperatures. Measured COP values of the proposed model varied between 0.85 and 1.04. The generator was designed and fabricated for optimal performance and could be rapidly transfer to the industrial applications, The system was found to be applicable and ready to produce the required conditioning effect without any additional load to the engine The proposed system decreases vehicle operating costs and environmental pollution caused by the heating system as well as causing a lower global warming. Simple experiments were carried out to examine the performance of the generator heat shown the benefit of exhaust gases as an alternative heating source.

This work presents an experimental study of an aqua-ammonia absorption system used for automobile air conditioning system, this system using the exhaust waste heat of an internal combustion diesel engine as energy source. The energy availability that can be used in the generator and the effect of the system on engine performance, exhaust emissions, auto air conditioning performance and fuel economy are evaluated. Because automotive air conditioning is one the most equipment that heavily uses CFC compounds and the leakage of CFCs from such air conditioners impact on the environment. The main purpose of this investigation to explore the feasibility of using waste energy to design the absorber and generation since these components are the most important components of absorption and they are directly influence the performance of the whole system. It has been found that the aqua -ammonia concentration effect the cooling capacity. The estimated cooling load for the automobile found to be within acceptable ranges which are about 1.37 ton refrigeration. The obtained results show that the coefficient of performance (COP) values directly proportional with increasing generator and evaporator temperatures but decrease with increasing condenser and absorber temperatures. Measured values for generator, absorber, and evaporator and condenser temperature were recorded and the coefficient of performance of the system varied between 0.85 and 1.04. The main components of the absorption cycle were designed and fabricated for optimal performance and could be rapidly transfer to the industry, The system was found to be applicable and ready to produce the required conditioning effect without any additional load to the engine. The proposed system decreases vehicle operating costs and environmental pollution caused by the heating system as well as causing a lower global warming.

In this study, the combustion characteristics and emissions of compression ignition diesel engine were measured using a biodiesel as an alternative fuel. The tests were performed in Chemical and Mechanical Engineering department laboratories at steady state conditions for a four stroke single cylinder diesel engine loaded at variable engine speed between 1200-2600 rpm. The waste vegetable oil (cocking oil) used in this investigation transferred from Tafila Technical University restaurant collected and disposed in a suitable way. The testing results show without any modification to diesel engine, under all conditions dynamical performance kept normal, and the B20, B5 blend fuels (include 20%, 5% biodiesel respectively) led to satisfactory emissions at variable load. The experimental results compared with standard diesel show that biodiesel provided significant reductions in CO, and unburned HC, but the NOx was increased. Biodiesel has a 5.95% increasing in brake-specific fuel consumption due to its lower heating value. However, using B20 and B5 diesel fuel gave better emission results, NOx and brake-specific fuel consumption. The experimental results show that the fuel consumption rate, brake thermal efficiency, and exhaust gas temperature increased while the bsfc, emission indices of CO2, CO decreased with an increase of engine speed. Moreover, the engine power increased when increasing the biodiesel percentage varied from 1.23 to 3.2 for standard diesel while for B20 between 1.5 to 3.47.while brake specific energy consumption varied between 16.8 to 13.81 MJ/kW.kg for standard diesel, but for B5 found to be between 16.3 to 13 MJ/kW.kg. In particular, biodiesel produced with the addition of the peroxidation process had the lowest equivalence ratio and emission indices of CO2, CO. The emission of NOx among all of the test fuels found to be increased when using B5 and B20 instead of standard diesel and these results validate the data recorded by other previous work. Therefore, the peroxidation process can be used effectively to improve the fuel properties and reduce emissions when biodiesel is used.

Supplemental material, sj-pdf-1-wie-10.1177_0309524X211027356 for Potential of wind energy in Medina, Saudi Arabia based on Weibull distribution parameters by Khaled S AlQdah, Raed Alahmdi, Abdulrahman Alansari, Abdulrahman Almoghamisi, Mohanad Abualkhair and Muhammad Awais in Wind Engineering