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The absorption refrigeration system driven by low grade heat sources, especially the waste heat sources, becomes more and more attractive in recent decades. However, most traditional absorption systems cannot achieve a high utilization rate of the waste heat with limited heat capacity. These systems are usually designed to obtain heat in the generator, which means that the waste heat sources cannot be utilized to the temperature lower than the generator temperature. This paper proposed a new structure heated by heat conduction oil in the generator and electric heating rings around the stripping section. This structure can simulate the temperature-distributed heat sources when the electric heating rings work. It can also simulate a traditional generator when the electric heating rings do not work. Influences of different heat distributions are analyzed in detail in this paper. The results show that the heat sources utilization rate will increase with the increase of the heat in the stripping section, while the coefficient of performance will be negatively affected by the increasing heat in the stripping section. By optimizing the heating structure, the coefficient of performance can be similar to that of a traditional system when the heat is just added in the middle and lower part of stripping section. The optimum utilization rate of heat sources in this test model can reach 1.8 times to that of a traditional system. Under this heating model, the lowest temperature required in the heating section is 82 °C when the heat conduction oil inlet temperature is 169 °C. It is much lower than the temperature inside the generator, which is 137.3 °C.

The use of non-edible vegetable oils as diesel engine fuel is a green solution which fosters energy security and reduces dependency on fossil fuels. Canola and jatropha plant seeds were adopted in this study based on their different physicochemical properties. Transesterification was used to upgrade the seed-derived oils into diesel grade oil. The engine performance, combustion behavior and emissions associated with biodiesel and its blends were studied. Results showed that biofuels have better performance when compared to a diesel. Significant reduction in emissions even high engine loads was achieved. The performance analysis of the test results showed that the brake specific fuel consumption values were slightly higher compared to diesel. Due to the shortage in studying the engine performance and emissions using the CFD techniques, a home-made code, COMMENT code, has been developed for the solution of optimization problems related to development and operation of ICEs. According to the different statistical analysis, the results were in good agreement with the experimental data with an average error of 2.7%.