A steady state analysis method was developed for gas networks with distributed injection of alternative gas. A low pressure gas network was used to validate the method. Case studies were carried out with centralized and decentralized injection of hydrogen and upgraded biogas. Results show the impact of utilizing a diversity of gas supply sources on pressure distribution and gas quality in the n...

A unique normalized radial pressure profile characterizes the bed of a gas-solid vortex reactor over a range of particle densities and sizes, solid capacities, and gas flow rates: 950-1240 kg/m3, 1-2 mm, 2 kg to maximum solids capacity, and 0.4-0.8 Nm3/s (corresponding to gas injection velocities of 55-110 m/s), respectively. The combined momentum conservation equations of both gas and solid ph...

Condensate banking around wellbores can significantly shorten the production from gas-condensate reservoirs. Several approaches to mitigate this issue have been proposed in literature, among which gas injection comes out with promising results. This method’s efficiency has largely investigated at core and field scales, but underlying flow phenomena taking place pore-scale are still poorly under...

We report two cases of surgical removal of a retained subfoveal perfluorocarbon liquid (PFCL) bubble through a therapeutic macular hole combined with intravitreal PFCL injection and gas tamponade. Two patients underwent pars plana vitrectomy with PFCL injection for rhegmatogenous retinal detachment. In both cases, a retained subfoveal PFCL bubble was noticed postoperatively by funduscopy and op...

the first step in dealing with the behavior of an engine on ng mode is the installation of a suitable gas fueling system on the engine. two generations of gas fueling systems which were studied and installed on research engine were mixer type and sequential system type. the results, including performance, emissions and fuel consumption, were recorded and analyzed. the results showed that the se...

Abbreviations: aBDC, after bottomdead center; aTDC, aft bottomdead center; bTDC, before top dead center; CA50, cra fraction reaches to 50%; CI, compression ignition; COVime indicated mean effective pressure; DI, direct injection; DIS DOI, duration of injection (first DOI1, second DOI2); EGR, homogenous charge compression ignition; IMEP, indicat injection ratio; MPRR, maximum pressure rise rate;...

In the most application of nozzle with gas-liquid two-phase flow, the quality of mixture in exhaust of nozzle is the most important parameter as well as the flow velocity. On the other hand, in some industrial application, such as water injection in forced induction (turbocharged or supercharged) internal combustion engine the spray quality is the main goal of designing. In this case and for im...

In order to find out the advantages and disadvantages of various development methods of coal bed gas, the experimental block provided by the field is studied, the component calculation model is established by CMG numerical simulation software on the basis of fine geologic modeling. Four development schemes are designed which are depleted development, development of hydraulic fracturing, develop...

Numerical modeling of direct hydrogen injection and in-cylinder mixture formation is performed in this paper. Numerical studies on direct-injection hydrogen engines are very limited due mainly to the complexity in modeling the physical phenomena associated with the high-velocity gas jet. The high injection pressure will result in a choked flow and develop an underexpanded jet at the nozzle exit...