Heavy crude oil is a valuable energy resource that is very abundant but also very viscous which complicates exploitation of these resources. One efficient and environmentally friendly heavy oil recovery technique uses exothermic oxidation reactions with a small amount of the oil reacting with oxygen in the injected pressured air. However, the lack of a thorough fundamental understanding of the complex multiple physicochemical and thermal processes in the reservoir limits broad use of this technique. In the past decade, our research group has conducted fundamental research in this field, including "The basic heat release characteristics and key factors affecting moderate temperature oxidation", "coke formation and chemical properties", "reaction model for low asphaltene heavy oil", "combustion regimes for high temperature oxidation at various operating conditions", and "reservoir scale simulations of the moderate temperature oxidation technique". Experimental systems were constructed to measure the heat release, the product properties and the transport properties during the heavy oil oxidation. Multiscale numerical simulations were developed for pore-scale, lab-scale and reservoir-scale studies to understand the coupling mechanisms at different scales. These research results have improved our fundamental understanding and promoted industrial applications of this heavy oil recovery technique in China.

Accurate variable speed characteristics are needed for water source heat pumps (WSHP) to design variable speed controls to adjust refrigerant flow rates in heat pumps and air conditioners. The system capacity can then be regulated to match the compressor loads to the heating or cooling needs to improve the energy efficiency and lower energy costs. The motor and compression characteristics of WSHP were modeled to include the coupling between the motor speed and the torque characteristics and compression characteristics. An analytical model is given for a variable speed hermetic scroll compressor that describes various factors, such as the drive frequency, suction pressure, and discharge pressure as a function of the compressor speed. The model was validated experimentally using R22 and R134a in an experimental WSHP with variable speed control using frequency conversion. The results show that the analytical model properly describes the variable speed characteristics and provides a control strategy for adjusting the capacity of scroll compressors to match the heat pump or air conditioner operating conditions.