The Design And Implementation Of Natural Gas Calculation Software Based On GB-T 21446-2008 Standard

The orifice flowmeter is the primary measurement for natural gas, which is one of the most important clean energy, in our nation.On the basis of the current mainstream level of gas flow measurement, combine with the market quo, this thesis developed a natural gas measurement software system, which is composed of two primary parts and etc. The infrastructure of the system is derived from GB/T 21446-2008 national standards, and the gas flow compression factor is mainly based on section 2 of GB/T 17747.2-2011 national standards, respectively. The implementation of system is developed on.Net 4.5 framework with C# compiler.With surveyed comparison of gas flow measurement mechanism domestically and internationally, this paper proposed and implemented a gas flow computing scheme which is combined with industrial demand. Firstly, this paper studied the principle and structure of gas flow measurement algorithm, and designed a complete algorithm with binging principles and key parameters of the gas transport pipeline. Next, on the basis of the algorithm to achieved an integrated system which contains gas flow calculation, the orifice diameter design calculation and the pipe diameter design calculation. Finally, gained commercialized protection through cryptographic message authentication code to implement access control system with user authorization and authentication mechanism.The reuse rate of the system is improved meanwhile the upgrades, maintenance and secondary development costs is reduced by the notion that the core computing functions separately packaged as a DLL. The iterative algorithm for compression factor is optimized by secant method to improve overall efficiency of the system, in order to achieve the demand that fast gas flow calculation for real-time monitoring. Moreover, the system introduced error compensation to obtain higher accuracy. At last, the system implemented pipe diameter estimation, which is derived from existing gas flow calculation algorithm and orifice diameter estimation algorithm, tests show that the error is acceptable. The gas flow calculation, orifice diameter estimation and pipe diameter estimation of the system would provide industrial designing reference.