Baorui Wang

Study on the pre-ignition temperature variations of wire insulation under overload conditions in microgravity by the functional simulation method

A functional simulation method was applied to study the pre-ignition temperature variations of wire insulation under overload conditions in normal gravity. A simplified heating mode was proposed to theoretically investigate the wire heating process. Results of the temperature variations of wire insulation prior to ignition in normal gravity, but under reduced pressures, were obtained and compared with microgravity experimental results in order to investigate the effects of pressure and current on the pre-ignition thermal features of the wire insulation. Results show that the functional simulation method was effective to simulate the natural convection heat transfer effect on the wire insulation, which is a useful alternative approach to predict the pre-ignition thermal features of wire insulation by overload over a long duration in a microgravity environment.

Numerical Simulation of Pollutant Emissions in a Can-Type Low NOx Gas Turbine Combustor

A research program is in development in China in order to realize a demonstrator of combined cooling heating and power system (CCHP) with net electrical output around 100kW by using of a can-type micro gas turbine. In this paper, numerical simulations were completed to investigate the pollutant emissions in a can-type low NOx gas turbine combustor. Based on the analysis of the computational fluid dynamics (CFD) results, a Chemical Reactor Network (CRN) model was set up to simulate the pollutant emissions in the combustor with detailed gas-phase chemical kinetic mechanism of GRI-Mech 3.0. The CRN consists of a number of ideal reactors of the perfectly stirred reactors (PSR) and plug flow reactors (PFR) in series and parallel structures. Two types of CRN models were designed. One is relatively simple, another is more complex. The results show that the complex CRN model corresponds with the actual combustion process better. The trends of nitrogen oxides (NOx) and carbon monoxide (CO) varying with the equivalence ratio were conducted. Effects of the inlet temperature and pressure on NOx and CO emissions were also presented in this paper. At last, the numerical results are compared with the experimental results.Copyright

Experimental Study of Combustion on a Micro Gas Turbine Combustor

A research program is in development in China as a demonstrator of combined cooling, heating and power system (CCHP). In this program, a micro gas turbine with net electrical output around 100kW is designed and developed. The combustor is designed for natural gas operation and oil fuel operation, respectively. In this paper, a prototype can combustor for the oil fuel was studied by the experiments. In this paper, the combustor was tested using the ambient pressure combustor test facility. The sensors were equipped to measure the combustion performance; the exhaust gas was sampled and analyzed by a gas analyzer device. From the tests and experiments, combustion efficiency, pattern factor at the exit, the surface temperature profile of the outer liner wall, the total pressure loss factor of the combustion chamber with and without burning, and the pollutants emission fraction at the combustor exit were obtained. It is also found that with increasing of the inlet temperature, the combustion efficiency and the total pressure loss factor increased, while the exit pattern factor coefficient reduced. The emissions of CO and unburned hydrogen carbon (UHC) significantly reduced, but the emission of NOx significantly increased.Copyright