Experimental Study On The Performance Of Small Solar Updraft Tower In The Climate Region

Solar updraft tower (SUT) power plant is a unique system using solar energy, which consists of three main parts: the chimney, turbine, and collector. In tropical climate conditions, especially in Malaysia, the application of solar chimney can be deemed more competitive compared to other renewable energy systems. In this study, one prototype with a dimension of 3.5 m in diameter for the collector and 5 m height for the chimney, was built in Melaka, Malaysia. Vital parameters such as temperature field, pressure, humidity, and air movement were measured using data logger and stored using non-volatile memory. The most exciting finding was that the temperature and pressure difference was significantly seen during the experiment along the day. There was a significant surge for the humidity in the morning with an average of above 95% and the ambient temperature was approximately 35 °C due to low solar radiation. The humidity kept decreasing after sunrise due to the greenhouse effect produced in the solar collector. With the collection of these critical parameters, a solar chimney power plant was adequate to function and generate power from solar radiation in a country such as Malaysia, which is based in the equatorial region. These studies are limited as the analysis focused mainly for high radiation and did not investigate efficiency during low solar radiation. The addition of heat storage underneath the collector with current techniques is another direction of research for continuous system operation, particularly during low solar radiation. It is proposed that the synthesis of these factors should be extensively explored in future studies coupled with the application of heat storage

Design and optimizing of geometric for solar updraft tower using computational fluid dynamics (CFD)

There are many experimental and analytical approaches that have been physically proven in the last few decades for the Solar Updraft Tower (SUT) concept to provide energy from solar radiation. Solar chimneys with their potential advantages have gained more attention by fully utilising solar radiation energy to generate air movement by stack pressure. This movement is driving the heated air through the chimney channel and then drawing colder air through the building in a continuous cycle. A parametric study on the geometry of the solar updraft tower is carried out with a different slope angle of collector, different inlet height of collector and different diameter of chimney collector inlet height with fixed solar radiation at 800 W/m2. A validated model is compared with the experimental prototype constructed by the University of Zanjan, Iran. The result shows an incredible improvement in the power generated by a collector with 0 degree and the best entrance gap of collector and chimney diameter at 0.05 m and 0.05 m respectively. The findings and results are discussed and suggested for future works

MODERN MANNED, UNMANNED AND TELEOPERATED EXCAVATOR SYSTEM

This paper presents a re-evaluation on the modern development and practical use of manned, unmanned and teleoperated construction vehicles in universities around the world, which focuses on the use of robotized excavators. Unmanned operation is becoming synonymous in the extreme environment operation. The operation is also becoming important in order to increase working efficiency and situational awareness. The review includes the theoretical, experimental and practical applications of such technology in the present days, particularly for excavators. Various innovation and control methods have been studied over the years by various entities, which provide the significant contribution by the scientific community to the progressing world.

Computational Simulation of Boil-Off Gas Formation inside Liquefied Natural Gas tank using Evaporation Model in ANSYS Fluent

Research on the waste energy and emission has been quite intensive recently. The formation, venting and flared the Boil-off gas (BOG) considered as one of the contribution to the Greenhouse Gas (GHG) emission nowadays. The current model or method appearing in the literature is unable to analyze the real behavior of the vapor inside Liquefied Natural Gas (LNG) tank and unable to accurately estimate the amount of boil-off gas formation. In this paper, evaporation model is used to estimate LNG Boil-Off rate (BOR) inside LNG tank. Using User Define Function (UDF) hooked to the software ANSYS Fluent. The application enable drag law and alternative heat transfer coefficient to be included. Three dimensional membrane type LNG cargos are simulated with selected boundary condition located in the United States Gulf Coast based on average weather conditions. The result shows that the value of BOR agrees well with the previous study done with another model and with International Marine organization (IMO) standard which is less than 0.15% weight per day. The results also enable us to visualize the LNG evaporation behaviors inside LNG tanks

The effect of different aspect ratio and bottom heat flux towards contaminant removal using numerical analysis

Cubic Interpolated Pseudo-particle (CIP) numerical simulation scheme has been anticipated to predict the interaction involving fluids and solid particles in an open channel with rectangular shaped cavity flow. The rectangular shaped cavity is looking by different aspect ratio in modelling the real pipeline joints that are in a range of sizes. Various inlet velocities are also being applied in predicting various fluid flow characteristics. In this paper, the constant heat flux is introduced at the bottom wall, showing the buoyancy effects towards the contaminant’s removal rate. In order to characterize the fluid flow, the numerical scheme alone is initially tested and validated in a lid driven cavity with a single particle. The study of buoyancy effects and different aspect ratio of rectangular geometry were carried out using a MATLAB govern by Navier-Stokes equation. CIP is used as a model for a numerical scheme solver for fluid solid particles interaction. The result shows that the higher aspect ratio coupled with heated bottom wall give higher percentage of contaminant’s removal rate. Comparing with the benchmark results has demonstrated the applicability of the method to reproduce fluid structure which is complex in the system. Despite a slight deviation of the formations of vortices from some of the literature results, the general pattern is considered to be in close agreement with those published in the literature

Simulation of Tele-Operated Electro-Hydraulic Actuator and Excavator's Boom

This paper, we present our study called TeleOperated Hydraulic Actuator which implying the usage of remote-controlled hydraulic system to control a mini excavator from a distance. Mini excavator comprises several motion mechanisms such as of swing, boom, arm and bucket. Simulation on the tele-operated electro-hydraulic actuator on boom mechanism has been conducted. The entire hydraulic system is modeled and simulate by using MATLAB software. The simulation result is discussed and described in order to analyze several system characteristics, given a certain working condition, within the simulation perio

Effect of Soot Particle Diameter to Soot Movement in Diesel Engine

Soot is one of the end product produced from the combustion of diesel engine. It can adversely affect the performance of the engine. It can cause the lubricant oil to be dirty thus increase its viscosity. These will results to frequent change of lubricant oil. Therefore, the focus of this study is related to the mechanism soot particles movement during the combustion process in the cylinder of diesel engine. The study of the path movement of soot particles from the initial position where it was formed to the last position was carried out. To analyze their movements, the data formation of soot particles was obtained through the simulation of combustion engine using Kiva-3V software which was used in previous investigation. The data that were obtained from the Kiva-3v simulation were velocity vectors of the soot, fuel, temperature, pressure and others. This data is used in the MATLAB routine to calculate the location of soot particles in the combustion chamber. Mathematics algorithm which is used in the MATLAB routine is trilinear interpolation and 4th order of Runge Kutta. In this study, the influence of soot particles diameter with different angular (θ) is included in the calculation to determine its movement. Results from this study shows that if the size of soot particles is bigger, the probability of the movement of soot particles to the combustion chamber wall is high thus contaminating the lubricant oil

Analysis of Soot Particle Movement in Diesel Engine under the Influence of Drag Force

The formation of soot is influenced by the composition of air entrainment and structure of hydrocarbon in the fuel. Soot will then form during combustion in a diesel engine. Some of the soot particles will be released from the engine through the exhaust nozzle and some will stick to the cylinder walls. The soot that sticks to the cylinder wall can affect the lifetime of the lubricant oil. Subsequently this will decrease the durability of the diesel engine. By understanding the movement of the soot particles, the effect to the engine can be decreased. Therefore, the initial position and last position of soot particle was recognized through this study. The data for the formation of soot particles in the diesel engine was obtained from previous investigation. The study of soot movement at 8° crankshaft angle under the influence of drag force with different radial, axial and angular settings were carried out using a MATLAB routine. The results showed that the movement of soot particle will change with different parameter settings. Besides that, comparison of the results of soot particle movement influenced by drag force and without drag force has been carried out. It was observed that drag force caused shorter soot particle movement path and moves them away from the cylinder wall

Numerical Analysis on the Effects of Cavity Geometry with Heat towards Contaminant Removal

Contaminants are recently discovered at the joint of large piping system and causing defect to industrial product. A computational analysis can be used as a solution of the hydrodynamic contaminant removal without any modification needed. In this paper, the effect of heat is introduced to analyze the heat transfer and flow field in a channel with cavity heated at the bottom sides coupled with different shape of cavity. The cavity shape used comes with three shapes i.e. square, triangle and semicircle. The process of fluid dynamic in a cavity is modeled via numerical solution of the Navier–Stokes equations using Cubic Interpolated Profile (CIP) method. By using the simulation of hydrodynamic contaminant removal, the flow of streamlines and vortices pattern was investigated in the cavities. In order to remove all of the contaminant, hydrodynamic need to take part in this simulation which is flow from the inlet of the channel and create vortices to remove it from the cavities. The result shows that the percentage of contaminant removal is higher for semicircle cavity with higher Grashof number. The result also indicates that vortices formation is highly dependent on the cavity geometry and creates a buoyancy effect

Mini acceleration and deceleration driving strategy to increase the operational time of flywheel hybrid module

This paper presents a new driving strategy to increase the operational time of flywheel hybrid module. The flywheel hybrid module contains low cost mechanical parts which installed on the small motorcycle. Based on normal driving cycles characteristics, the Mini-AD driving strategy is develop. It is involved a series of short or mini acceleration cycle and short deceleration cycle on top of the normal driving cycles. The new strategy is simulated for flywheel hybrid module, aimed for acceleration phase only. Simulations show that the new driving strategy can increase the operational time of flywheel hybrid module up to 62.5%