Showing papers in "International Journal of Automotive and Mechanical Engineering in 2015"

Effect of Nano-Particles on the Performance and Emission of a Diesel Engine using Biodiesel-Diesel Blend

Abstract: n experimental investigation was conducted in a six - cylinder, four-stroke diesel engine to establish the effects of Multi Wall Carbon Nano Tubes (MWCNT) with the dosing levels from 2.5 to 30 ppm with the waste vegetable oil (WVO) methyl esters fuel that was produced using the transestrification process, and subsequently, the WVO methyl ester was blended with diesel fuel in the proportion of 80% of diesel and 20% biodiesel by volume (B20). The Carbon nanotubes (with nano-structure (1/3) Chiral Metal and (2/3) semiconductor zigzag particles with the length of 10 μm and diameter of 5 nm with purity rate of 95%) were blended with the biodiesel fuel .The CNTs we re blended with the biodiesel with the aid of ultrasonicator. The whole investigation was conducted in the diesel engine using the following fuels: neat diesel fuel (D100), 20% biodiesel and 80% diesel by volume (B20), as well as B20 and CNT blended fuels accordingly.The experimental results revealed a considerable enhancement in the performance parameters for the CNT blended biodiesel fuels compared to the neat biodiesel and neat diesel fuel (power increased up to 17%, torque increased 18%, bsfc decreased 38.5%). Emission parameters for the CNT blended decreased compared to neat diesel and neat biodiesel fuels (HC decreased up to 22%, CO emission decreased 14%).CNT nano-additives are considered as a propitious fuel - borne catalyst to improve the fuel properties, owing to their enhanced surface area/volume ratio, quick evaporation and shorter ignition delay characteristics that help to improve the performance parameters of engine and decrease emissions

Comparative study of diesel engine performance and emission with soybean and waste oil biodiesel fuels

Abstract: The study investigated the engine performance and emission using biodiesel from soybean oil and waste cooking oil. The fuel properties of these biodiesels were determined using ASTM D6751and EN 14214 standards. The fuels were tested in a multi-cylinder diesel engine with an electromagnetic dynamometer and a 5-gas analyser was used for emission analysis. The result shows that the thermal performance of the engine slightly decreases with increase of the biodiesel blends ratio (i.e. B5, B10, B15, B20 and B50). On the other hand, emission decreases with the increase of biodiesel blends. The reduction in emissions was different for both biodiesels. Waste oil biodiesel showed better trends of emissions reduction with increase of the biodiesel percentage compared with soybean biodiesel. The brake specific fuel consumption (BSFC) of both biodiesels is (6.05%, 9.13%, 12.36% and 18.57% for soybean) and (8.17%, 11.40%, 17.71% and 14.96% for waste cooking oil) higher than diesel, respectively. However, soybean biodiesel consumed less fuel and produced more power and torque compared to waste oil biodiesel. The study concluded that B10 soybean biodiesel blend produced more consistent and expected results than waste oil biodiesel from the performance and emission point of view.

Mechanical properties of bamboo reinforced epoxy sandwich structure composites

Abstract: In the composite industry, natural fibres have great potential to replace synthetic fibres like carbon and glass, due to their low cost and environmentally friendly materials Bamboo is emerging as a versatile reinforcing fibre candidate because this woody plant has a number of advantages, such as being naturally strong, biodegradable and abundantly available In this study, a compression test with a crosshead displacement rate of 1 mm/min was conducted on square and triangular honeycomb core structures based on bamboo-epoxy composites so as to study their specific energy absorption Both square and triangular honeycomb structures were manufactured by the slotting technique Initially, a tensile test with the same crosshead displacement rate was conducted to study the tensile strength of unidirectional bamboo-epoxy composites with 0°, 45° and 90° fibre orientations Bamboo-epoxy composite laminates were fabricated by applying a hand lay-up technique The experimental data showed that the unidirectional bamboo-epoxy composite with 0° orientation offered the highest tensile strength This indicates that the bamboo is stronger when parallel to the tensile axis Meanwhile, the triangular honeycomb bamboo-epoxy structure offered about 10% more energy absorption than the square honeycomb structure, which indicates that the smaller cell size of honeycomb is able to absorb more energy than the bigger one

Nanofluids heat transfer enhancement through straight channel under turbulent flow

Abstract: The need for high thermal performance thermal systems has been eventuated by finding different ways to enhance heat transfer rates. This paper introduces and analyzes numerically the heat transfer enhancement of nanofluids with different volume concentrations under turbulent flow through a straight channel with a constant heat flux condition. Solid nanoparticles of TiO2 and CuO were suspended in water as a base fluid to prepare the nanofluids. CFD analysis is conducted by FLUENT software using the finite volume method. The heat flux considered is 5000 W/m2, the Reynolds numbers are 104–106 with a constant volume concentration of 1–3%. Based on the analysis of the numerical results, it is found that the heat transfer rates and wall shear stress increase with increase of the nanofluid volume concentration. It appears that the CuO nanofluid significantly enhances the heat transfer. Furthermore, the numerical results are validated with the literature data available and show good agreement, with 4% deviation. The study concluded that the enhancement of the friction factor and Nusselt number is by 2% and 21%, respectively for the nanofluids at all Reynolds numbers. Therefore, nanofluids are considered to have great potential for heat transfer enhancement and are applied in heat transfer processes.

Characteristics of solar thermal absorber materials for cross absorber design in solar air collector

Abstract: The solar thermal absorber is an integral component of a solar air collector, especially in determining the overall performance of a solar air thermal system. The type and shape of material will have a direct impact on the operating temperature and thermal energy storage effect of the solar air thermal collector. This paper focused on the investigation of aluminum and stainless steel hollow square rods in terms of their solar thermal absorber performance. Comparisons between different materials and coatings were conducted in order to determine their impact in solar thermal absorber applications. Experiments were conducted on both materials with flat-black coated and non-coated surfaces of aluminum (6063) and stainless steel sets respectively. Both sets were exposed under 585 W/m2 radiation and the temperature response was recorded. A significant improvement was shown to result from the application of flat-black coating against non-coated material, with maximum temperatures of 67.2oC and 48.3oC respectively. It was observed that for the hollow square metal absorber the heating and cooling characteristics can be established by means of the relation between the surface and inner air temperatures of the absorber. This method can assist in temperature profiling of hollow square metal for solar thermal application.

Experimental study of heat transfer enhancement in automobile radiator using Al^2^O^3 water-ethylene glycol nanofluid coolants

Abstract: An experimental study on heat transfer enhancement in an automobile radiator using Al2O3/water–ethylene glycol (EG) nanofluids is carried out. Heat transfer enhancement studies can help in the design of lighter and more compact radiators for the same given load, which in turn can improve the fuel economy of the automobile. A closed loop experimental setup is designed using a commercial automobile radiator for the study. The effect of adding EG to water on the overall heat conductance (UA) is studied using two mixtures of water–EG proportions, 90:10 and 80:20 (by volume). They showed a reduction in UA by 20% and 25% respectively. Experiments have also been done using Al2O3/water–EG nanofluids. The nanofluid was prepared using an 80:20 mixture and 0.1% (vol.) of Al2O3 nanoparticles. The addition of nanoparticles enhanced the heat transfer performance by 37 %. All the experiments have been conducted at a constant coolant flow rate and coolant inlet temperatures varying from 40 C to 70 C. The results showed that the heat transfer performance of the radiator reduced with the addition of EG and increased with the addition of nanoparticles to the water–EG mixture.

Effects of accelerators on the cure characteristics and mechanical properties of natural rubber compounds

Abstract: The effects of different accelerators on the cure characteristics and mechanical properties of sulphur-cured natural rubber (NR)-based compounds are investigated. Three accelerator systems, with mercaptobenzothiazole disulphide (MBTS) as primary accelerator and diphenylguanidine (DPG) and Zn-2-mercaptobenzothiazole (ZMBT) as secondary accelerators, were incorporated into a premixed NR compound referred to an industrially used rubber mat formulation by using the melt mixing method. The cure characteristics, rubber crosslink density and mechanical properties were the focus in the present study. It is observed that the synergistic effect of the MBTS/DPG combination imparts the shortest scorch time, highest cure rate and highest crosslink density compared with the MBTS/ZMBT and MBTS/ZMBT/DPG combinations. Mechanical tests indicate that the tensile strength and modulus of MBTS/DPG are enhanced owing to improved cure activation in initiating sulphuric crosslinking, but the tear strength is decreased compared with the others. This study demonstrates that the MBTS/ZMBT/DPG system is the most effective in enhancing tear strength by 4.5 % compared with MBTS/DPG system, as well as other mechanical properties. Analyses on tear behaviours and scanning electron microscope (SEM) micrographs of the fractured surfaces of tear test samples correspond well with the results of tear strength.

Multi-objective optimization of minimum quantity lubrication in end milling of aluminum alloy AA6061T6

Abstract: The purpose of this research is to optimize the process of minimum quantity lubrication (MQL) in the end milling of AA6061T6 using multi - objective genetic algorithm approach . R esponse surface methodology coupled with a central composite design of experiments is used for modeling. Data is collected from a vertical CNC milling cent e r and the input parameters are cutting speed, table feed rate , axial depth of cut and the minimum quantity lubrication flow rate . A nalysis of variance at a 95% confidence level is implemented to identify the most significant input variables on the CNC end milling process. Optimization of the responses is done using a multi - objective genetic algorithm. A m ulti - criteria decision making utility is used to find among the feasible range of optimum design s for the operating parameters and the responses. An iterative multi - criteria decision making algorithm is used to find the best design among those obtained from multi - objective optimization with respect to the given conditions. The best design obtained for the equal weightage case is the design at 5252 rpm, with a feed rate of 311 mm/min, a depth of cut of 3.47 mm and MQL flow rate at 0.44 ml/min.

Performance and emission comparison of Karanja (pongamia pinnata), Pithraj (aphanamixis polystachya), Neem (azadira chtaindica) and Mahua (madhuca longofolia) seed oil as a potential feedstock for biodiesel production in Bangladesh

Abstract: This paper investigates the production of biodiesel (BD) from karanja (Pongamia pinnata), pithraj (Aphanamixis polystachya), neem (Azadira chtaindica) and mahua (Madhuca longofolia) seed oil through acid esterification, followed by the investigation on the transesterification process and physicochemical properties of oils. This study also includes their effects on engine performance and emission on a direct ignition (DI) diesel engine. A maximum 9 of 6% by volume methyl ester (biodiesel) was obtained from mahua oil at methanol concentration of 22vol%, catalyst concentration of 0.5wt% and a temperature of 55°C and at the same condition 94%, 92% and 91% biodiesel extraction was experienced for neem, pithraj and karanja seed oil respectively. The diesel-biodiesel blend (B10) has been used during the test run and it was found that all of the fuels showed performance closer to the neat diesel. Among all the biodiesels, karanja showed better performance compared to the other three. On the other hand, high oxygen content of biodiesel causes less CO and NOx emission. It was experimentally found that mahua emits the least amount of CO and NOx which were 44.44% and 38.3% respectively compared to the neat diesel. Results indicate that these oils are potential biodiesel feedstock and can be used as an alternative to the diesel fuel in the near future. Desirable engine performance and tail pipe emissions are also observed during the experimental investigation.

Morphology and tensile properties of thermoplastic polyurethane-halloysite nanotube nanocomposites

Abstract: The high aspect ratio of nanoscale reinforcements enhances the tensile properties of a pure polymer matrix. Researchers have reported the morphology and tensile properties of thermoplastic polyurethane and halloysite nanotube (TPU-HNTs) nanocomposites, formed through compression moulding processes. Few researchers have reported on TPU-HNTs formed through injection moulding. Therefore, the present work investigates the tensile properties of TPU and HNT nanocomposites via injection moulding. TPU and HNTs were mixed using a brabender mixer with concentrations ranging from 1wt.% to 15wt.% and varying mixing parameters (i.e., mixing speed, mixing time, and mixing temperature). Tensile bars were injection moulded by varying the moulding parameters (i.e., injection temperature, injection time, and injection pressure). A significant increment of tensile strength was found at 1wt.% HNT reinforcement. TPU-HNT nanocomposite with 1wt.% reinforcement exhibited tensile strength of 24.3 MPa, which was higher than that of pure TPU. The Young’s modulus of the TPU-15wt.% HNT nanocomposite was 21.5 MPa. Thus, TPU-HNT had improved mechanical properties, compared to pure TPU, due to the addition of a nanofiller.

Mechanical properties and microstructure of precipitation-hardened Al-Cu-Zn alloys

Abstract: Many automobile components are made from aluminium and its alloys because of their suitable properties. Metals and their alloys are usually subjected to heat treatment in order to improve their properties. Thus, the effect of precipitation hardening on the mechanical properties and microstructure of sand cast aluminum alloys was investigated. The cast AlCu-Zn alloy samples were heat-treated at 460 °C for 2 hours, quenched in water and then age-hardened at 160 °C for 5 hours. Tensile, impact and hardness tests were carried out on the heat-treated and the as-cast Al-Cu-Zn alloys samples. The surface morphology of both the as-cast and the precipitation hardened samples was observed using digital metallurgical microscope. The ultimate tensile strength of the precipitation hardened samples A2 (81.2Al: 1.56Cu: 8.33Zn) and B2 (81.7Al: 3.25Cu: 6.16Zn) are 173.42 N/mm 2 and 168.02 N/mm 2 , respectively. These values are higher than those of the as-cast samples A1 and B1, which are 168.02 N/mm 2 and 157.84 N/mm 2 , respectively. The precipitation hardened Al alloy samples also displayed higher hardness, impact energy and elongation than the as-cast samples, indicating improved properties. The presence of coarse reinforcing intermetallic phases was observed in the as-cast samples as compared to the well-distributed fine grain size microstructure of intermetallic phases in the precipitation hardened samples. It can be concluded that precipitation hardening improves the mechanical and microstructure properties of aluminum alloys and thus will find wider applications in automobile industries for the production of components and parts.

Influence of hot burned gas utilization on the exhaust emission characteristics of a controlled auto-ignition two-stroke cycle engine

Abstract: A controlled auto-ignition (CAI) two-stroke cycle engine suggests an exceptional aspect and promising future for internal combustion engines (ICEs), such as a higher power-toweight ratio, higher combustion efficiency and lower exhaust gas emissions. Conventional two-stroke cycle engines emit higher exhaust gas emissions and offer lower fuel saving economy. Most of these drawbacks can be addressed if CAI combustion is associated with a two-stroke cycle engine. An experimental investigation is carried out based on a single-cylinder CAI two-stroke cycle engine using Internal and External Exhaust Gas Recirculation (In-EGR and Ex-EGR) and fuels with different octane numbers to investigate the exhaust emissions characteristics. The experimental results indicate a remarkable improvement in the engine's exhaust gas emissions. The concentration of uHC and CO emissions decreased with application of In/Ex-EGR. However, NOx emission increased with the use of In-EGR

Integration of vehicle dynamics control systems with an extendable bumper for collision mitigation

Abstract: The aim of this paper is to enhance crashworthiness in the case of vehicle-to-barrier full frontal collision using vehicle dynamics control systems integrated with an extendable bumper. The work carried out in this paper includes developing and analysing a new vehicle dynamics/crash mathematical model and a multi-body occupant mathematical model. The first model integrates a vehicle dynamics model with the vehicle’s front-end structure to define the vehicle’s body crash kinematic parameters. In this model, the antilock braking system (ABS) and the active suspension control system (ASC) are cosimulated, and its associated equations of motion are developed. The second model is used to capture the occupant kinematics during full-frontal collision. The numerical simulations show that in the case of using the extendable bumper, the crash energy absorbed is considerable compared to traditional structure. Therefore, the minimum vehicle crumble zone’s deformation is obtained when the ABS alongside under pitch control (UPC) is applied with the extendable bumper. The minimum pitch angle of the vehicle body and acceleration are obtained when the ABS alongside UPC technique is applied without the extendable bumper. The occupant deceleration and the occupant's chest and head rotational acceleration are used as injury criteria. The longitudinal displacement and acceleration of the occupant is extremely decreased when the extendable bumper is used. It is also shown that the VDCS can affect the crash characteristics and the occupant safety positively, whereas the rotations angle and acceleration of the occupant chest and head are significantly reduced.

A mean value model for estimation of laminar and turbulent flame speed in spark-ignition engine

Abstract: Flame velocity is the main parameter for determination of combustion propagation in a spark-ignition engine. The first part of combustion that consists of flame initiation and flame kernel growth has laminar velocity. For a certain radius of kernel growth, transition to turbulent flame occurs; afterwards, the flame can be described as turbulent. This paper investigates the relationship between fuel properties and engine operation parameters, their influence on flame velocity and their ability to calculate the time delay from ignition to 50% mass fraction burned (MFB) that is used for adjusting the spark advance. The GT-Power software is employed to simulate the combustion process of a spark-ignition (SI) engine. The flame speed mean value model is applied to determine the laminar flame speed under different amounts of unburned mixture, temperatures and pressures. The results show that mixture with less than the stoichiometric ratio has the greatest laminar flame speed. At higher temperature, the difference between poor and rich mixture is significant for laminar flame speed. On the other hand, the relationship between turbulence intensity and engine speed is almost linear. The cylinder pattern used to create turbulence during the intake and compression strokes defines the slope between the engine speed and turbulent flame speed. The mean value flame speed model was capable of determining the combustion phasing and predicting spark ignition in advance.

Whole-body vibration exposure of Malaysian taxi drivers

Abstract: During their whole working time, taxi drivers are usually seated. Additionally, longterm exposure to whole-body vibration while driving may lead to diseases and adverse health conditions such as lower-back pain. The objective of this study is to investigate the relationship between measurable whole-body vibration and lower-back pain. This study was conducted on two highways: Kuala Lumpur–Karak Highway and the North– South Highway. A tri-axial seat accelerometer was placed at the point of contact between the driver and the seat pad. The assessment of whole-body vibration measurement is according to ISO 2631-1. Excessive whole-body vibration has been evidenced as leading to lower-back pain. Taxi drivers are recommended to drive no more than the allowable exposure limit. In this study, the whole-body vibration does not exceed the allowable exposure limit. Therefore, the taxi drivers in this study do not have lower back pain.

A descriptive analysis of factors contributing to bus drivers' performances while driving: a case study in malaysia

Abstract: This paper presents the factors contributing to a bus driver’s performance. A bus driver’s performance is important in ensuring the smoothness and safety of a journey. Descriptive survey research design was adopted for the study. The target population was the bus drivers along the east coast of Malaysia (Pahang, Terengganu and Kelantan). The data for the research was collected by using a questionnaire.

Energy audit and waste heat recovery system design for a cement rotary kiln in Ethiopia: A case study

Abstract: This paper deals with the energy audit and heat recovery system modeling and design , taking a cement factory in Ethiopia as a case study. The system is a dry type rotary kiln equipped with a sixth stage cyclone type preheater , pre - calciner and grate cooler. The kiln has a capacity of 3 , 000 tons/day. The energy auditing has been performed based on the data collected from control volume of the kiln system for a ten - month period . The result shows that 25.23% of the total heat input is released to the environment through the preheater and an other 15.58% through the cooler exhausts. The west heat recovery system (WHRS) can produce a gross power of 5.26 MW as long as the kiln is i n operation . The generated power can cover all the electrical energy consumption of the kiln system whether there is a power supply from the grid or not. Therefore, the company can save up to 536,222.10 USD per year due to the production of clinker using their own power source and avoiding the loss sustained by the company due to power interruption from the grid

Comparison of numerical simulation and experimental study on indoor air quality of air-conditioned office building in desert climate

Abstract: This paper is a study of the air temperature distribution of an air-conditioned office room equipped with a double-glazed window in a desert climate. The study includes both experimental and theoretical works using a computational fluid dynamics (CFD) simulation program. The experimental results were compared with the CFD program results. The commercial computational fluid dynamics ANSYS CFD V.13.0, solver FLUENT software, and three-dimensional flow finite difference of k-e for analysis and validation experimental work were used. The main objective of the study is to evaluate the temperature difference between the outdoor and indoor environments, as well as the distribution of air temperature in the room. The computational results for internal air temperatures of the office ranged from 23°C to 26°C, while the airflow velocity was low at less than 0.3 m/s. The temperature differences between the indoor and outdoor spaces varied between 9 °C and 15 °C. Good agreement was achieved between the computed and measured temperature results. The error percentage varied from 0.3% to 0.8%. The experimental and numerical results showed that well-designed double glazing can reduce the emission of sunshine and heat inside desert buildings, even using the northeastern facade, in sunny climates.

Effect of ZnO Nano Materials on Grinding Surface Finishing

Abstract: The surface roughness is a variable often used to describe the quality of ground surfaces as well as to evaluate the competitiveness of the overall grinding system. The main study of this paper is a grinding process was performed on the P20 tool steel by changing the grinding conditions, including the depth of cut, the grinding passes, the type of wheel, and the cutting fluid supply in the experiment. The main objective of the study is to investigate the effect of ZnO nanofluid on the grinding surface finishing and wheel wear. The machined surface of selected specimens undergoes SEM to assess the surface integrity. Artificial neural network was used to predict the surface roughness and recognise the trend of the surface roughness. The result showed the reduction of 47 % surface roughness value in grinding with ZnO nanofluid. Neural network predicts accurately and can recognize the roughness trend

Experiments on vortex-induced vibration of a vertical cylindrical structure: Effect of low aspect ratio

Abstract: Studies in offshore engineering have shown that vortex-induced vibration (VIV) of a slender offshore riser can be fundamentally different from that of a cylindrical spar structure. Under similar environments, the primary difference between the two structures affecting vortex shedding relates to the aspect ratio (length to diameter ratio, L/D). In the present investigation, careful experiments were carried out on the VIV of an elastically mounted cylinder with a varying aspect ratio. Experiments were conducted by forcing the vertical cylinders in still water. Of particular interest was the measurement of the response amplitude, hydrodynamic forces, Strouhal number (St) and the lock-in region while the aspect ratio of the cylinder varied from L/D = 0.5 to L/D = 13. The experiments were conducted in the subcritical flow region (7.4 × 10 3 < Re < 2 × 10 5 ), corresponding to a range of reduced velocity Ur from 2 to 14. Comparisons with experimental results obtained from the literature showed meaningful trends. It was found that the response amplitude of the structure decreased as the aspect ratio was reduced. The decrease in response amplitude was accompanied by a decrease in the correlation length of the vortex shedding and the hydrodynamic forces experienced by the structure. The Strouhal number and lock-in region, too, showed a significant reduction with a lower aspect ratio. It is apparent that the aspect ratio influenced the occurrence of the VIV, which affected the hydrodynamics of the fluidstructure interaction between the fluid and the bluff body.

Effects of isentropic efficiencies on the performance of combined cycle power plants

Abstract: This study deals with modelling and performance enhancements of a combined cycle power plant. Several configurations of CCGT power plants are proposed by thermal analysis. The integrated model and simulation code for exploiting the performance of the CCGT power plant is developed utili zing MATLAB code. A different strategy for the CCGT power plant's operational modelling is suggested for power plant operation, to improve overall performance. The effect of is e ntropic efficiencies on the performance of the CCGT power plant is based on rea l CCGT power plants. An extensive thermodynamic analysis of the modifications of the most common configuration enhancements has been carried out. The simulati o n results for the HRSG configurations show that the maximum power output (1000 MW) occurred in th e supplementary triple - pressure reheat CCGT at high isentropic compressor efficiency. Furthermore, with the triple - pressure reheat CCGT and higher isentropic turbine efficiency the maximum overall efficiency was about 58.3%. In addition, the proposed CCGT system improved the thermal efficiency by 1.6% and the power output by 11.2%. Thus, the isentropic efficiencies and CCGT configurations have a strong influence on the overall performance of the CCGT

Simulation of fuel economy for Malaysian urban driving

Abstract: By understanding the implications of real-world driving conditions, improved fuel economy via a strategy of key technologies can be implemented to assist fuel economy validation during development programs. Vehicles in real-world driving conditions regularly travel at idle, low and medium speeds, particularly for urban driving, and this has a crucial weight in overall vehicle fuel economy, given the residencies at the lower engine speed and load region. This paper presents the validation of the derived engine conditions representing Malaysian actual urban driving in an attempt to formulate representative fuel economy data. The measurements were conducted through on-road urban driving within Kuala Lumpur to establish representative driving conditions. The effectiveness of the proposed conditions was then validated in terms of fuel economy using a simulation. The discrepancy between the fuel economy in the proposed conditions and the real-world measurements has improved, falling to 11.9% compared to 43.1% reported by the NEDC.

Effects of flow parameters on the performance of vertical axis swirling type Savonius wind turbine

Abstract: Wind tunnel experiments were carried out on a geometrically optimal swirling Savonius turbine by varying flow parameters to determine their effects on power and torque coefficients. The optimum geometrical configuration used in this experiment was adopted from an earlier study that features 0.20 blade overlap ratio, 195˚ blade arc angle, and 1.06 rotor aspect ratio of a 320 mm diameter rotor with closed top end plate. The parameters considered in this experimental are the hot air temperature, hot air mass flow rate, hot air inlet diameter of swirl chamber, and the free-stream wind velocity. The results indicate that higher hot air temperature and hot air mass flow rate promotes performance of the turbine while power coefficient reached maximum at a certain hot air inlet diameter. Tests on the optimum geometry at four wind velocities revealed that power coefficients are higher in higher wind velocities.

Characteristics of solar energy radiation on typical summer and winter days in Kuwait

Abstract: The energy received by solar collectors for power generation is limited to various conditions. The average data on solar irradiation are normally used to determine the potential of solar energy at any location. However, the variation of solar energy due to seasonal differences could affect the actual performance of the collectors, consequently leading to poorly justified system installations, which are high in cost. In this work, the characteristics of solar energy radiation in Kuwait were studied by measuring irradiance and comparing the data of selected time periods in two extreme seasons. A pyranometer, mounted two meters above the ground on a tubular beam in a shade-free area at a solar energy laboratory in Kuwait was used to measure irradiance on three consecutive days in summer and winter. The radiation data were recorded at five-minute intervals in each season for comparison. It was found that the average irradiance energy in the winter was up to 61% less than in the summer. In addition, the study revealed that the day-to-day variation of irradiance in winter (31%) was approximately 6.5 times higher than in the summer (4.8%). Clearly, the operation of solar power generation systems in the area during winter would face significant day-to-day fluctuations. As a result, this would necessitate frequent operation of backup power systems in order to meet the electrical power load demand.

Direct injection of water mist in an intake manifold spark ignition engine

Abstract: The purpose of this study is to investigate the effects of water mist (WM) injected directly into an intake manifold spark ignition (SI) engine WM flows through a nozzle at the throttle body of the four-cylinder four-stroke multi-point injection engine for testing the performance of exhaust emission system The water is pumped in mist form into the intake manifold with an air-fuel mixture through the nozzle, which is located on the throttle body Experimental work and simulation methods are combined by the presence and absence of WM addition, and the performance as well as emission produced by the engine is analyzed The Gamma Technologies (GT) methods are used to simulate the model with and without WM addition The experimental results indicate that the standard engine performance can be used to validate the simulation model The engine measures include various parameters such as brake power, torque, volumetric efficiency, spark advance timing, and the concentration of CO and NOx with water and without water addition to the SI engine (ie, the power, torque, volumetric efficiency of the engine is increased up to 10%) The emission of NOx is found to be significantly reduced and that of CO does not change

Simulation of ignition delay time of compressed natural gas combustion

Abstract: This research mainly aims to simulate compressed natural gas (CNG) combustion to create a valid reaction mechanism that can be used to determine the effects of temperature, pressure, equivalent ratio, diluents composition, and CNG composition on the ignition delay time profile in a combustion reaction. The combustion reaction involves many elementary reactions; therefore, in this study, the stages of important reactions were identified by sensitivity and rate of production analyses. In this study, CNG was represented by three components, namely, methane, ethane and propane (CH4/C2H6/C3H8). The model is arranged according to the literature and validates the experimental data for CH4/C2H6/C3H8/O2/N2 mixture in the temperature (T) range of 1039–1553 K, initial pressure (P) range of 1.1–40.0 atm, and equivalent ratio (ɸ) = 0.5, 1.0, and 2.0 using a shock tube. The software used in this study is Chemkin 3.7.1. The ignition delay time profile for CNG combustion has been successfully reproduced by the kinetic model. The slowest ignition delay time for the composition of 88% CH4/8% C2H6/4% C3H8 with an initial temperature range of 1100–1500 K is 37.2 ms (P=2 atm, T=1100 K, and ɸ=2.0) and the fastest IDT is 0.033 ms (P=30 atm, T=1500 K, and ɸ=0.5). For constant ethane or propane composition, the increase in methane composition will cause slower ignition.

Experimental Study Of Split Air Conditioner With And Without Trombone Coil Condenser As Air Conditioning Water Heater

Abstract: International Journal of Automotive and Mechanical Engineering (IJAME) ISSN: 2229-8649 (Print); ISSN: 2180-1606 (Online) Volume 12, pp. 3043-3057, July-December 2015 ©Universiti Malaysia Pahang

Characteristics of K3-VEI4 engine performance using swirl generator, air intake tank and exhaust gas recirculation modification

Abstract: The paper studies the characteristics of K3-VEi4 engine performance using swirl generator, air intake tank and exhaust gas recirculation (EGR) modification. Engine weight is reduced prior to the other modifications in order to reduce inertia loss. Then an air intake tank is mounted before the throttle body in order to increase the air intake pressure. A swirl generator is mounted at the air intake manifold to blend the air-to-fuel mixture. EGR is installed to improve the engine performance by reusing the unburnt fuel and increasing the air intake temperature. The effects of the engine modifications on the engine performance are analyzed on a chassis dynamometer. Performance parameters such as engine power and brake specific fuel consumption (BSFC) are then analyzed for each modification individually and then the whole system combined. The result shows that a gain of about 117% in terms of power can be achieved with the different modifications put together and a reduction of around 62% on the BSFC. These improvements are obtained at low rpm, corresponding to city driving. A more thorough study of the EGR tapping position would further improve its implementation to increase engine performance and fuel efficiency.

Engagement slip controller development based on actuator displacement for an electro-mechanical friction clutch system

Abstract: This paper describes a controller development for an electro-mechanical friction clutch (EMFC) system for automotive applications and especially for vehicles that use continuously variable transmission. The work focuses on developing an EMFC engagement controller based on experimental work using a Proportional Derivative (PID) controller algorithm to engage the dry friction clutch. The EMFC is electromechanically actuated using a DC motor system, such that a smooth engagement process can be performed satisfactorily. To develop the controller, the dynamic behaviors of the EMFC system are investigated by performing tests on the EMFC bench-test. Results from this experiment show that the percentage of slip between the input and output shaft of the EMFC system depends on the input speed and output torque. Therefore, by applying slip control, engagement of the EMFC can be controlled and achieved for any input speed and torque during the standing start of a vehicle.