Applied Mechanics and Materials Vols. 465-466

Abstract: The present study examines the performance of a single zone building integrated with PV Trombe wall (PV-TW) in term of thermal load reduction and electrical energy production by varying PV Glazing types (i.e. Single Glazing, Double glazing, Double glazing filled with gas (Argon)). TRNSYS software is used for simulation in which inputs like climatic conditions, building construction details, thermal properties of materials, detail of PV-TW and orientation of building is inserted. By comparing the results of all three types of glazing it is found that PV Double glazing filled with argon shows significant reduction in mean air duct temperature, hence reduces the PV cell temperature and increases power production of PV panel. Also solar radiation captured by massive wall of PV-TW is reduced by using PV Double glazing filled with argon as compared to other types of glazing, which further reduces thermal load inside the building.

Abstract: In this report, the modeling and simulation of a double pass solar air absorber was carried out using combination of Simscape and Simulink modeling tools. The solar system air mass flow rate and the porous media were critically investigated by using local weather data of Seri Iskandar, Perak, Malaysia. Optimal inlet air flow rate of 0.034kgm^-2s^-1 was obtained and one of the packed beds, sandstone extended the thermal transfer period of solar collector system by 1150s which displayed good agreement with the reported model and experimental outcomes. The results obtained have shown that it is a promising alternative tool for solar thermal experimentation modeling.

Abstract: Biodiesel is an alternative, decomposable and biological-processed fuel that has similar characteristics with mineral diesel which can be used directly into diesel engines. However, biodiesel has its drawbacks which are more density and viscosity compared to mineral diesel. Alcohol additives implementation such as ethanol could reduce significantly the density and viscosity of the biodiesel. In this study, biodiesel (20%)-ethanol (5%)-diesel (75%), biodiesel (20%)-methanol (10%)-diesel (70%), biodiesel (20%)-ethanol (15%)-diesel (65%), biodiesel (20%)-ethanol (20%)-diesel (60%) and standard mineral diesel as a baseline fuel are tested in a Mitsubishi 4D68 diesel engine. Those test fuels are investigated under the same operating conditions at three different engine loads; 20%, 40% and 60% at a constant engine speed of 2500 rpm to determine the engine performance, combustion and emission of the diesel engine. Overall, biodiesel-ethanol-diesel blends show higher brake specific fuel consumption than mineral diesel especially at higher ethanol concentration. As ethanol proportions in blends increase, CO emissions increase, while NO emissions are reduced. Also, biodiesel-ethanol blend with 5% ethanol is more effective than other biodiesel-ethanol blends for reducing CO emissions and improve the combustion.

Abstract: T his paper presents mathematical model for regenerator of liquid desiccant air conditioning system. Regression analysis was used to get the relation between enthalpy and humidity ratio. Performance of regenerator is highly affected by varying the flow direction between air & desiccant thus to get proper regeneration results counter-flow configuration is considered. Previous studies show better regeneration results for counter-flow direction of air to desiccant. Validation is done by comparing results of present study the experimental results of previous studies and comparison was found to be quite satisfactory. Based on above mathematical model performance of regenerator was analyzed. The purpose of this research was regeneration of liquid desiccant from its dilute-solution form to strong-solution.

Abstract: Transesterification of palm oil with methanol using a potassium hydroxide (KOH) catalyst to form fatty acid methyl ester (FAME) commercially known as biodiesel was performed in a millichannel reactor. In this study, a transparent Teflon tubular reactor with the inner diameter of 1.59 mm at 60 °C was carried out to produce FAME. Residence time was changed by changing the tube length and flow rate. The residence time of 69 s is required to achieve more than 88% of ester content. The relationship between ester content and flow pattern was also investigated.

Abstract: Energy is very important in our daily activity especially in commercial and industries sector. These requirements have increased from time to time and as the result it is significantly end up with high energy demand and high energy cost. Thermal Energy Storage (TES) can be used as an alternative solution to reduce high energy demand and to reduce energy cost. The main reason of using TES system is to shift high energy demand from peak period to off peak period. Meanwhile, for building owner is to reduce energy cost by take opportunity low cost energy during off peak period. The purpose of this study is to develop a split unit air conditioner by substituting the circulation system with chilled water. The research was conducted by fabricating an air-conditioning blower unit integrated with cool thermal energy storage. Chilled water was used as medium to stored cool thermal energy. Water pump was used to circulate chill water from storage tank to evaporator and return back to storage tank. Series of experiments were conducted to test cooling performance of the developed product to produce cooling effect inside a chamber room. The experiments were conducted in a chamber room located at Block C6, Universiti Tun Hussein Onn Malaysia. Finally, from experiment found 0.15 meter³ of chilled water had successfully maintained chamber design temperature more than 140 minutes.

Abstract: Wood pellets are compressed wood particles that are used as fuel. Pellets are gaining popularity and are commonly used in some areas of India owing to the cost effectiveness. One of the major reasons is the increase in the cost of primary fuels and concerns about global climate change. For research and development work and for the production of small quantities of pellets for specific applications, it is important to have a low-cost apparatus or machine for making pellets. The paper discusses the local design and manufacturing of a dual-mode pelletizing machine. It can be powered either electrically or manually. Therefore, it can be used by both rural as well as urban dwellers. It can be a backup in conditions of power failure, and can also prove a boon in rural areas where there is no electricity. The objective of this work was to analyze, design and fabricate a model for a Dual Mode Pelletizing Machine which would be used for production of pellets on small scale and can be powered by either electrical motor or human pedaling. The Pelletizing Machine was designed, fabricated and experiments were performed to obtain pellets from sawdust, powered by electric motor as well as human pedaling.

Abstract: The aim of the research work described in this paper is to use computational fluid dynamics (CFD) to optimize the geometry of a multi-stage evaporative cooling device to investigate the effects on its performance by varying the primary inlet to mixing st ack area ratio. The studies do not simulate external wind effects or a wind catcher and the ambient air inlet was modelled as an opening. The computational domain was modelled to represent a typical small building having an overall cooled space volume of 1350 m³. The general result suggests that the combined effect of the increased mass flow rate and increased evaporative potential of the incoming air resulted in the observed increase in sensible cooling power.

Abstract: Global focused on green technology in the midst of energy escalating costs and the risk of global warming. Wind power is one of the realistic strategic choices to solve the problems. This paper focused on the development of a permanent magnet generator for a vertical axis wind turbine. High starting torque issued problem to vertical axis wind turbine. Therefore, application of magnetic levitation resolved the problem. Magnetic levitation reduced wind turbine weight acting by the gravitational force. The prototypical structure on customize design are analyzed on its geometry and output voltage are measured.The prototype produced is capable for voltage generation of up to 5.48 volts or more depending on the number of coils and the constant speed of the air flow.

Abstract: Biofuels based on vegetable oils offer the advantage being a sustainable and environmentally attractive alternative to conventional petroleum based fuel. The key issue in using vegetable oil-based fuels is oxidation stability, stoichiometric point, bio-fuel composition, antioxidants on the degradation and much oxygen with comparing to diesel gas oil. This provides a critical review of current understanding of main factor in storage method which affecting the biodiesel properties and characteristics. In the quest for fulfill the industry specifications standard; the fuel should be stored in a clean, dry and dark environment. Water and sediment contamination are basically housekeeping issues for biodiesel. Degradation by oxidation yields products that may compromise fuel properties, impair fuel quality and engine performance. The effect of storage method on the fuel properties and burning process in biodiesel fuel combustion will strongly affects the exhaust emissions.