COMPARISON OF NUMERICAL AND EXPERIMENTAL RESULTS FOR OVERTOPPING DISCHARGE OF THE OBREC WAVE ENERGY CONVERTER

OBREC is the latest innovation of overtopping wave energy converter (WEC) which is coalesced with the rubble mound breakwaters. The acquisition of wave overtopping in a front reservoir and consequently releasing process through turbine is the concept of energy production in OBREC. The physical scale model studies of overtopping discharge of the OBREC have recently been done by previous researcher in wave flume at Aalborg University. This paper demonstrates the overtopping behavior of OBREC device using a VOF method with capabilities to solve RANS equation in the numerical suite Flow3D. The purpose of this research is to validate the overtopping discharge performance of the numerical model against the experiments of the OBREC. Based on the observation, the results have shown a good agreement between the validation and physical experiment

Feasibility of using solar assisted rigid wind–sail as a power saving device on boats

The usage of alternative energy beside fossil fuel in maritime industry is necessary due to the fluctuating fuel cost. In order to reduce the operational cost by reducing the fuel consumption, some ships are equipped with solar-wind assisted devices. The lower oils consumption in ships could reduce environmental pollutions and increase cruising range. This study investigates the feasibility of using solar assisted rigid wind–sail as a power saving device on University Malaysia Terengganu’s (UMT) research boat. The attachment of solar assisted rigid wind-sail device may affect the performance, operation and stability of the boat. Generally, the performance of boat will increase when there are additional energies. Thus, the operational cost of the boat may decrease due to lower oil usage. Attempts were made to study the feasibility of using solar assisted rigid wind-sail in technical aspects including stability and performance as well as operational and economical aspects. The results of the study shown that the application of solar assisted rigid wind-sail to UMT research boat reduced the annual cost of operation from USD 20390 to USD 17815.9. It can also save up to 20% of power consumption. Further, the attachment of solar assisted rigid wind-sail to UMT research boat does not affect the stability of the boat and the stability of boat still meet the IMO requirement. Therefore, it can be summarized that the solar assisted rigid windsail has a high potential as an alternative to the conventional fossil fuel ships in the future

Study of incorporating kite or balloon technology to UMT Research Boat

Rising oil prices, increasing competition in the maritime industry, climate change and pollution are significantly more prevalent among the causes of the search of alternative energy other than the use of crude oil. One of the energy that is suitable to use is wind energy because it is easily found, especially at the ocean. The large kite has been used by several types of ships as one of the propulsion system to move the ship. This study is done for the feasibility of incorporating kite technology to move the UMT boat in Terengganu waters that have been selected to save the consumption of diesel. The amount of power saving was calculated using the formulae from the previous research. Then, economic assessment was carried out based on amount of power saving. Using kite propulsion technology, fuel consumption can be reduced thus resulting in lower and operation costs on the particular routes. The results of the economic assessment indicate that, annual average cost for boat with kite sail is lesser than annual average cost for boat without kite sail. It is expected that the capital investment in the new device will be recovered within 9 years

Comparison Of Numerical And Experimental Results For Overtopping Discharge Of The Obrec Wave Energy Converter

OBREC is the latest innovation of overtopping wave energy converter (WEC) which is coalesced with the rubble mound breakwaters. The acquisition of wave overtopping in a front reservoir and consequently releasing process through turbine is the concept of energy production in OBREC. The physical scale model studies of overtopping discharge of the OBREC have recently been done by previous researcher in wave flume at Aalborg University. This paper demonstrates the overtopping behavior of OBREC device using a VOF method with capabilities to solve RANS equation in the numerical suite Flow3D. The purpose of this research is to validate the overtopping discharge performance of the numerical model against the experiments of the OBREC. Based on the observation, the results have shown a good agreement between the validation and physical experiment