Analysis of the Influence of the Length and Diameter of a Connecting Gas Pipeline on the Working Processes of a Hybrid Piston Power Machine Based on Application of Fluctuations in Gas Pressure in the Injection Lines

2018 ◽  
Vol 54 (3-4) ◽  
pp. 247-252
Author(s):  
V. E. Shcherba ◽  
V. N. Blinov ◽  
A. M. Paramonov ◽  
A. V. Grigor’ev ◽  
I. E. Lobov
2009 ◽  
Vol 79-82 ◽  
pp. 1169-1172 ◽  
Author(s):  
Yu Hua Chen ◽  
Yong Wang ◽  
Zheng Fang Wang

In-service welding is a kind of important method to ensure the integrality of oil gas pipeline and the thermal cycle of which is significant for repairing. Used SYSWELD to establish model and simulate thermal cycle of in-service welding on X70 steel gas pipeline, compared thermal cycles of in-service welding and air-cooling welding, studied the influence of gas pressure and flow rate on thermal cycle. The result shows that peak temperature of the coarse grain in heat affected zone (CGHAZ) of in-service welding is similar to air cooling welding, but the cooling time of t8/5, t8/3 and t8/1 decreases at certain degree. Peak temperature of CGHAZ of in-service welding doesn’t vary match with gas pressure and flow rate either. t8/5, t8/3 and t8/1 decrease when gas pressure increases. t8/5 varies with the gas pressure linearly. When the pressure is less than 4MPa, t8/3 and t8/1 decrease rapidly while gas pressure increases. When the pressure is more than 4MPa, t8/3 and t8/1 decrease slowly while gas pressure increases. t8/5, t8/3 and t8/1 decrease when the flow rate increases. When gas flow rate is less than 10m/s, t8/5, t8/3 and t8/1 decrease rapidly while flow rate increases. When gas flow rate is more than 10m/s, t8/5, t8/3 and t8/1 decrease slowly while flow rate increases.


Author(s):  
V.E. Shcherba ◽  
A.Y. Ovsyannikov ◽  
E.Y. Nosov ◽  
G.S. Averyanov ◽  
S.A. Korneev ◽  
...  

In this paper, a new promising scheme of a two-cylinder single-stage piston hybrid power machine with fluid flow due to vacuum at suction is examined. A prototype is developed, and an experimental stand is created. An analysis of the influence of the coolant flow on the working processes of the machine is carried out theoretically and experimentally. The results obtained show that an increase in the coolant consumption leads to a decrease in the input technical work in the process of compression, an increase in the output technical work in the process of decompression, a reduction of the work losses in the process of discharge and an increase of the work losses in the process of suction. Based on the conducted experimental studies it is established that the optimal indicative value of the efficiency for the experimental machine under study is in the range of 300 – 400 ml/min and the relative increase in the indicative efficiency is within 7 %.


Author(s):  
D. J. Zhang ◽  
Q. W. Wang ◽  
M. Zeng ◽  
L. Q. Luo ◽  
F. Wu ◽  
...  

Compact and efficient recuperator is an important component of a microturbine system. To ascertain the optimum gas cavity configuration of the recuperator in a 100kW-microturbine system, a numerical study of flow performance has been done. The main parameters to change in different cases are cone angle of the gas pipeline, α and depth of the pipeline in the gas cavity, L. By comparing the gas pressure drop, Δp and the gas outlets velocity nonuniformity, Su, we found that the case with α = 5° and L = 370mm is the best configuration. Comparing with the worst case, it may greatly decrease the velocity nonuniformity by 73.3% while the corresponding pressure drop increases only 8%.


Author(s):  
Yi Liao ◽  
Changlei Liu ◽  
Tao Wang ◽  
Taolong Xu ◽  
Jie Zhang ◽  
...  

Landslide is the main factor threatening the operation safety of long-distance gas pipeline, and the internal corrosion of pipeline will also seriously affect its reliability. Using LS-DYNA software, considering the interaction between pipeline and soil, a model of pipeline with defects crossing landslide is established based on the coupling of smoothed particle hydrodynamics and finite element method (SPH-FEM). The effect of the depth, number and spacing of pipeline defects and gas pressure on the mechanical behavior of pipeline is analyzed. The results show that the corrosion defects and gas pressure have little effect on the deformation of the pipeline. It is also found that when the gas pressure of the pipeline increases gradually from zero, the residual strength of the pipeline has a maximum value. Additionally, for the single corrosion defect, the maximum plastic deformation appears in the center of the corrosion defect, but for the double corrosion defect, it appears in junction of the corrosion defects. Furthermore, with the increase of landslide displacement, the plastic strain zone gradually extends along the circumference of the pipeline in these two kinds of defective pipelines. At the same time, the interaction between adjacent corrosion defects is found. The interaction is related to the defect spacing: within a certain range, the interaction increases with the increase of the defect spacing, the maximum equivalent stress appears at the junction of defects, and the stress concentration area expands along the circumferential direction. With the further increase of the spacing, the interaction disappears.


Sign in / Sign up

Export Citation Format

Share Document