A micro turbo-expander capable of high working speed was specially manufactured for use in an organic Rankine cycle (ORC).A series of tests were executed to examine the performance of the machine.In the experiment,the...A micro turbo-expander capable of high working speed was specially manufactured for use in an organic Rankine cycle (ORC).A series of tests were executed to examine the performance of the machine.In the experiment,the machine was tested under different inlet pressure conditions (0.2-0.5 MPa).Data such as the compressed air pressure,temperatures of the inlet and the outlet,rotational speed,and electric power generation were analyzed to discover underlying relationships.During the test,the rotational speed of the machine reached as high as 54 000 r/min,the peak value of the temperature drop between the inlet and the outlet reached 42 ℃,the maximum electric power generated by the motor-generator attached to the machine reached 630 W,and the efficiency of the machine reached 0.43.展开更多
The issue of navigation using binary pulsars is investigated in this paper.We show how the effect of the binary motion is incorporated in the navigation measurement equation.Necessary reference systems and time scales...The issue of navigation using binary pulsars is investigated in this paper.We show how the effect of the binary motion is incorporated in the navigation measurement equation.Necessary reference systems and time scales are introduced and the transformation between different time scales is derived.Based mainly on Damour and Deruelle's binary model and the TEMPO2 software,the timing model resolving the time delay from emission to arrival is established with the solar system,interstellar and binary system delays included,which retains all the terms exceeding 1 ns.The navigation measurement equation is thus built and the parameters needed are listed.A comparison is made between Sheikh's measurement equation and that in this paper.It is found that it is not necessary to introduce a fictitious SSB arrival time as Sheikh does.Near-Earth navigation for the Keplerian orbit in the case of observing one pulsar is investigated.The uncertainties of the orbit parameters are derived using the least square fitting method,which reveals that observing one pulsar enables one to navigate near-Earth spacecraft.展开更多
基金Project (Nos.50974150 and 50708105) supported by the National Natural Science Foundation of China
文摘A micro turbo-expander capable of high working speed was specially manufactured for use in an organic Rankine cycle (ORC).A series of tests were executed to examine the performance of the machine.In the experiment,the machine was tested under different inlet pressure conditions (0.2-0.5 MPa).Data such as the compressed air pressure,temperatures of the inlet and the outlet,rotational speed,and electric power generation were analyzed to discover underlying relationships.During the test,the rotational speed of the machine reached as high as 54 000 r/min,the peak value of the temperature drop between the inlet and the outlet reached 42 ℃,the maximum electric power generated by the motor-generator attached to the machine reached 630 W,and the efficiency of the machine reached 0.43.
基金supported by the National Natural Science Foundation of China (Grant No. 41074023)
文摘The issue of navigation using binary pulsars is investigated in this paper.We show how the effect of the binary motion is incorporated in the navigation measurement equation.Necessary reference systems and time scales are introduced and the transformation between different time scales is derived.Based mainly on Damour and Deruelle's binary model and the TEMPO2 software,the timing model resolving the time delay from emission to arrival is established with the solar system,interstellar and binary system delays included,which retains all the terms exceeding 1 ns.The navigation measurement equation is thus built and the parameters needed are listed.A comparison is made between Sheikh's measurement equation and that in this paper.It is found that it is not necessary to introduce a fictitious SSB arrival time as Sheikh does.Near-Earth navigation for the Keplerian orbit in the case of observing one pulsar is investigated.The uncertainties of the orbit parameters are derived using the least square fitting method,which reveals that observing one pulsar enables one to navigate near-Earth spacecraft.
