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The inelastic buckling resistances of wide flange beams are strongly influenced by residual stresses and initial imperfections. However, the resistances as evaluated from simple solutions presented in several popular design specifications are found to be considerably different. The present study thus develop a numerical solution in ABAQUS software to investigate the inelastic buckling moment resistances of rolled steel beams with compact sections and subjected to the effects of residual stresses and initial imperfections. The residual stresses are taken as provided in AISC, CSA S16, EC 3 specifications, while the initial imperfections are taken as the first lateral-torsional buckling mode with a magnitude limited in AISC, CSA specifications. Through comparisons between the specifications and the numerical solutions, one observes a significant difference between the moment resistances predicted by the specifications, in which the AISC predicts the highest values, while the EC 3 predicts the lowest moments. The moment resistances based on the present numerical models lie between the EC 3 and CSA solutions and they are relatively close to EC 3 solutions. Effects of load height positions on the inelastic buckling moment resistances are significant, as investigated in the present study

Using the laboratory-based fuel consumption models for predicting real-world fuel consumption requires the measurement of data under certain conditions to obtain high accuracy of predicted result. Therefore, it is necessary to develop a logging device for measuring the real-time fuel consumption and speed of vehicle on the road. This article presents a study on developing the on-board data logging device to collect real-world data of fuel consumption and speed for motorcycles with the update rate of 1 Hz. The instantaneous speed of the motorcycle was determined based on the rotational speed of the wheel and the wheel radius. Another module was used to determine the instantaneous fuel consumption rate (FR) though measuring the duration injection pulse. The relationship between the duration injection pulse and the injected amount of fuel was established with high correlation coefficient of 0.997. In addition, a filter was designed to remove noise in the dataset collected using the data logging device. The random errors in the speed and the FR profiles were detected and replaced, the percentage of these errors is 1.8% and 2.4%, respectively. The developed method is a precise one for transient fuel consumption and speed measurement. In chassis dynamometer test, the average deviation between steady speed measured by the chassis and the data logging device is only approximately 0.35%. At transient state, the biggest deviation between these two datasets is less than 3.5%. The average FR at steady speed measured by the developed method is slightly different from the one measured by the carbon balance method. The difference is 0.9%, 2.5%, and 0.25% at the speeds of 30 km/h, 50 km/h, and 70 km/h, respectively. Following the transient test cycle, the fuel consumption measured by the developed method is 4.35% lower than that determined by the carbon balance method.

In the Internal Combustion Engine (ICE) working operation, fuel is fed into the combustion chamber, where it is burnt in air to convert the chemical energy of fuel into heat according to the first law of thermodynamics. However, the amount of energy transformed into actual power is only 21-33% and 25-40% for gasoline engines and diesel engines, respectively. Consequently, about two-thirds of the remaining energy is lost due to the heat transfer to the surrounding environment, in which the heat energy removed by the exhaust occupies the largest proportion (about 30-35%). Therefore, utilizing the regenerative heat from the exhaust gases is a potential solution to improve the ICE’s efficiency. This paper presents the simulation results of the effect of heat exchange tube structure on waste recovery capacity in the system, which utilizes the heat of exhaust gases and cooling water of ICE based on Ansys Fluent. In addition, the boundary conditions, the flow, and exhaust temperature are determined by simulating the engine’s working process using AVL-Boost. This research shows that the heat utilization efficiency of exhaust energy can be achieved up to 34%, corresponding to a reasonable structure. This research’s study outcomes are the foundation to implement the complete design of the heat waste recovery system of ICE.