Efficient Mounting of a Tank for the Transport of Flammable Liquids on a Freight Vehicle

The design and construction of tanks used for the carriage of dangerous liquid materials fall within strict standards (i.e., EN13094:2015, R111). According to these standards, their supporting structures (Ss), used for the mounting of the tank on the freight vehicle, need to be able to sustain the developed stresses. Optimizing the number of supporting structures can lead to more efficient tank designs that allow the tank to transport more liquid material and need less time to be manufactured. In the present paper, the effect of the reduction of the number of supporting structures in (a) the structural integrity of the tank construction, (b) its dynamic behavior and (c) the load-sharing of the tank to the axles of the freight vehicle is investigated using the finite element (FE) method. As a case study a box-shaped tank mounted on a four-axle freight vehicle with a technical permissible maximum laden mass of 35 tn, five Ss are used. Four FE models with a decreasing number of Ss were built in ANSYS ® 2020R1 CAE Software and their structural integrity was investigated. For each design, a feasible design was developed and evaluated in terms of structural integrity, dynamic behavior and axle load distribution. The results of the FE analysis were reviewed in terms of maximum equivalent Von Mises stress and stress developed on the welding areas. Additionally, the axle-load sharing was qualitatively assessed for all feasible designs. The main outcome of this work is that, overall, the use of two Ss leads to a more efficient design in terms of the manufacturing and the mounting of the tank construction on the vehicle and on a more efficient freight vehicle. More specifically, the reduction of the number of Ss from five to two lead to reduction of the tank tare weight by 9.6% with lower eigenfrequencies.