This paper investigates the formation of the pollutant nitric oxides (NOx) in the low-nitrogen (N2) environment of methane oxycombustion in a spark-ignited (SI) internal combustion engine. Working fluid composition, N2 concentration, O2 concentration, compression ratio (CR) and spark-timing have...

A prototype of hydraulic free piston engine has been developed to achieve efficient energy conversion directly from chemical energy of fuel to hydraulic energy. In stable running condition, in order to verify the features of this kind of engine, the piston dynamics, combustion process and...

In a domestic central heating system, the phenomenon of microbubble nucleation and detachment on the surface of a boiler heat exchanger finds its origins in the high surface temperature of the wall and consequential localised super saturation conditions. If the surrounding bulk fluid is at...

Wind loads greatly affect the mechanical performance and tracking accuracy of heliostats. Therefore, the wind load must be accurately known to assure the operational reliability of heliostats. A simple wind load model was developed based on experiments on an actual heliostat rather than a wind...

A novel dual hot gas bypass defrosting (DHBD) method is developed to remove frost from the outside heat exchanger (HEX) of an air-to-air heat pump. The proposed method adopts two bypass lines of hot gas from the compressor: one is connected to the inlet of the outdoor HEX, and the other is...

When an air source heat pump (ASHP) unit operates in heating mode, frost can be accumulated on the surface of its finned outdoor coil which normally has multiple parallel circuits on its refrigerant side for minimized refrigerant pressure loss and enhanced heat transfer efficiency. On its...

Temperature distribution over a Solid oxide fuel cell (SOFC) surface is a crucial parameter for design of a SOFC stack. The selection of both materials and the operating point of a stack is heavily affected by temperature gradient. Temperature distribution can also be used for control and...