Crashworthiness of a Composite Bladder Fuel Tank for a Tilt Rotor Aircraft

The fulfilment of the crash is a demanding requirement for a Tiltrotor. Indeed, such a kind of aircraft, being a hybrid between an airplane and a helicopter, inherits the requirements mainly from helicopters (EASA CS 29) due to its hovering ability. In particular, the fuel storage system must be designed in such a manner that it is crash resistant, under prescribed airworthiness requirements, in order to avoid the fuel leakage during such an event, preventing fire and, thus, increasing the survival chances of the crew and the passengers. The present work deals with the evaluation of crashworthiness of the fuel storage system of a Tiltrotor (bladder tank), and, in particular, it aims at describing the adopted numerical approach and some specific results. Crash resistance requirements are considered from the earliest design stages, and for this reason they are mainly addressed from a numerical point of view and by simulations that treat both single components and small/medium size assemblies. The developed numerical models include all the main parts needed for simulating the structural behavior of the investigated wing section: the tank, the structural components of the wing, the fuel sub-systems (fuel lines, probes, etc.) and the fuel itself. During the crash event there are several parts inside the tanks that can come into contact with the tank structure; therefore, it is necessary to evaluate which of these parts can be a damage source for the tank itself and could generate fuel loss. The SPH approach has been adopted to discretise fuel and to estimate the interaction forces with respect to the tank structure. Experimental data were used to calibrate the fuel tank and foam material models and to define the acceleration time-history to be applied. Thanks to the optimized foam’s configuration, the amount of dissipated impact energy is remarkable, and the evaluation of tanks/fuel system stress distribution allows estimating any undesired failure due to a survivable crash event.

Impact of Sloshing on Fossil Fuel Loss during Transport

This study attempts to uncover the most common issue of fuel shortage faced by the oil and transportation industry worldwide. In Pakistan, petroleum is transported to the northern areas from the south coast. Currently, this is done using road tankers as a pipeline is still under construction. However, even after the pipeline becomes operative, road tankers would still be used for intra-city transport. Findings from this study can be used to determine the inter-city transport losses faced by oil companies. This study determines the hydrocarbons lost to the environment during inter-city road transport of petroleum. It takes nearly 2–3 days to complete a one-way trip with the fully loaded tank. Much work has been reported worldwide on hydrocarbon emissions, but nearly all of it has been done either for storage tanks/vessels or fuel tanks in rails/cars. The aim of this study was to investigate the actual amount of fuel lost to the environment due to the sloshing of liquid. Also, the results were expected to help in determining the extent of hazardous emissions resulting from road transport of petroleum. Hence, measures could be taken by the concerned authorities to mitigate the emissions if they exceeded the acceptable range. The sloshing was not found to contribute much in terms of vapor loss. Valve location was found to be important as no loss was obtained from the third compartment because the valve is to the right in this chamber. A negligible amount of fuel was lost from the first and second compartments per application of the brakes. Over a whole trip of 2–3 days, if the tanker braked 500 times, a total of 9–10 L would be lost to the environment.

Analysis of the Impact of Flyover Development on Communities in the Market

Traffic congestion that occurs almost everyday in Pekanbaru City has caused losses in travel time and economic losses such as waste of fuel, loss of productive time and health costs. One of the causes of this congestion is the growth of road infrastructure that is not proportional to the growth in the number of motorized vehicles. Besides that, the existence of Pasar Pagi Arengka at the Jl. HR Soebrantas and Jl. Soekarno-Hatta, Riau Province, has also added to the level of congestion. Overcoming this problem, the Riau government together with the Dinas Pekerjaan Umum (PU) of Riau Province built a flyover or overpass at Pasar Pagi Arengka junction to overcome the congestion problem. The research data was obtained by conducting a survey to the location through a questionnaire to the community around the flyover with the number of respondents determined as many as 60 respondents. Calculation analysis is performed using SPSS Statistics. The results of the study stated that the impact caused by the construction of a flyover at the intersection of Pasar Pagi Arengka in Pekanbaru, Riau Province, to the community was quiteinfluential.

Telemetry Data Prediction of Launch Vehicle Attitude Control Engine Using LSTM

The attitude control engine used by the launch vehicle is mainly composed of a pressurized gas cylinder, a pressure reducer, a tank, a duct, a pitch extension, a roll extension, a yaw extension, and a sinker extension. In this paper, a long short-term memory network is used to train the telemetry data transmitted from the temperature and pressure sensor points distributed in various positions of the attitude control engine, such that the state of the rocket attitude control engine can be deduced and predicted in real time through the data-driven digital twinning system. It is possible to detect potential data anomalies in advance and locate the faults, so that the control system can change the attitude control strategy in sufficient time to alleviate the fuel loss issue as well as positional deviation caused by minor faults, so as to better ensure the success of the mission.

An economic analysis of the proposed Dhaka–Chittagong Expressway in Bangladesh with the viewpoint of GHG emission reduction

Frequent road intersections in Dhaka–Chittagong National Highway (NH1), the major transport corridor of Bangladesh, significantly reduce the level of service of the corridor and eventually leads to inefficient fuel economy and excessive greenhouse gas (GHG) emission. In spite of upgrading NH1 into a four-lane highway, major road intersections reduce vehicle speed and increase congestion time and eventually burn fuel. Fuel expenses during this lost time cover no distance but increase vehicular emission within the vicinity of road and contribute to roadside temperature. Besides, the transport sector’s energy demand in Bangladesh is supported mostly by imported fuel that drains out foreign currency and inhibits GDP growth. Against the backdrop, the Government of Bangladesh is proposing to construct a four-lane expressway. The paper attempts to estimate the fuel loss savings, GHG emission reduction and economic benefit of constructing Dhaka–Chittagong Expressway. As the construction of the expressway paved a way for an increment of traffic growth by 10%, the study infers that the average lost time because of 36 intersections for a projected annual average daily traffic of 27,334 vehicles/day (in 2022). In addition to that, the fuel loss savings for various vehicle classes affect economic growth and the ensuing idling emission of EFI and MFI engines contributes to transport sector pollution. The study intends to expedite the fact that Dhaka–Chittagong Expressway would not only replace road interventions that reduce travel time cost, expenditures regarding vehicle operating and accident but also contributes cardinally to economic emancipation of the country. The estimated Benefit–Cost Ratio (BCR) was 1.23, net present value was 762.34 Million USD) and Economic Internal Rate of return was 18.27% of the proposed project.

VALUASI EKONOMI DAMPAK KEMACETAN LALU-LINTAS DI DKI JAKARTA

Congestion that occurs in the Sudirman area of economic impact on society. Congestion can lead to a reduction in income and decrease the economic benefits for workers who work in the Sudirman. The decline in the perceived economic benefits of the workers can be called with a loss. Losses felt by workers is the value of wasted fuel loss due to increased purchases of fuel oil (BBM), a decrease in productivity in the form of wasted time akbitat jammed seen from income and working time. In addition, there is a loss of value where there is a decline in the health of the costs incurred for treatment due to declining health and psychological pressure value losses due to traffic. Total economic losses due to the impact of congestion on Jl. Sudirman Rp 19,716,239,573,128 / year. The loss is derived from the value of inefficiency fuel oil (BBM) Rp 15,008,423,787,414 / year, the value of reductions in labor productivity Rp 2,871,644,285,714 / year, the value of psychological distress as a result of congestion Rp 525.800.000.000/tahun, and health value of USD 1,310,371,500,000 / year.Key word : Congestion, Economic Losses, Inefficiency, Jakarta ABSTRAK Kemacetan yang terjadi di Jakarta, khususnya di daerah Jalan Sudirman berpengaruh pada ekonomi masyarakat. Kemacetan ini telah berdampak pada pengurangan penghasilan dan penurunan manfaat ekonomi bagi pekerja yang bekerja di daerah Sudirman. Kerugian yang sangat dirasakan para pekerja adalah nilai kerugian dari pemborosan bahan bakar akibat peningkatan pembelian bahan bakar minyak (BBM), penurunan produktivitas berupa waktu yang terbuang akibat kemacetan. Selain itu, kemacetan lalu-lintas juga menimbulkan kerugian nilai ekonomi akibat penurunan kondisi kesehatan, sehingga menimbulkan biaya dalam bentuk biaya pengobatan, serta kerugian nilai tekanan psikologis karena kemacetan. Kerugian total ekonomi akibat dampak kemacetan di Jl. Jenderal Sudirman tersebut mencapai Rp 19.72 trilyun per tahun atau sekitar 1,6 persen dari nilai PDRB DKI Jakarta. Kerugian tersebut sebagian besar berasal dari kerugian akibat: inefisiensi Bahan Bakar Motor (BBM) (76 persen), penurunan produktivitas pekerja (15 persen), peningkatan biaya kesehatan (7 persen), serta kerugian akibat tekanan psikologis (3 persen).Kata Kunci: Kerugian ekonomi, metoda valuasi, inefisiensi