## 5 Conclusions  
In the design process of the traditional gas turbine engines, vast experiment tests are needed. To reduce unnecessary trials, a whole engine simulation tool is extremely needed in the preliminary design period. Considering the drawbacks of 0D analysis and 3D CFD calculation, the 2D throughflow analysis method is still an indispensable tool. For this purpose, a compressor simulation tool is first developed. Based on the average circumferential method, 3D N-S and Euler equations are transformed into 2D models. When they are involved in the simulation of the compressor, an improved inviscid blade force model considering the effect of the blade geometry is derived. (1) The inviscid blade force is attributed to the tangential difference of pressure in the blade passage and the gradient of the blade blockage factor. The former is to deflect the flow direction, and the latter is to reduce the flow path area. However, in previous research, the assumption is that gas flows along the average stream surface of the blade, and the effect of the blade geometry is not taken into consideration, which is not applicable in the CAM. (2) The improved inviscid blade force model is obtained from the analysis in a linear cascade on the subsonic condition. Through analyzing the results from the 3D calculation, it is observed that the spatially averaged pressure is nearly the same as the algebraic mean value of pressure on the pressure and suction side. Since the spatially average pressure has the same meaning as the pressure in CAM, it is thought to be reasonable to replace \(\frac{p_{+}+p_{p}}{2}\) with the pressure value obtained in CAM. (3) When compared with the 3D results, the maximum error of pressure along the streamwise direction decreases from 30.9% to 9.0%, based on the improved model on the subsonic condition. For the axial velocity, it drops from 21.0% to 7.5%. When the model is applied on the transonic condition, the maximum pressure error between CAM and 3D results in changes from 128.1% to 39.3%, and for axial velocity, the error is reduced  
Figure 34: Gridline of TA36 chosen for parameter comparison. Figure 35: Comparison of TA36′s parameters obtained from CAM and NUMECA: (**a**) the axial component of the inviscid blade force; (**b**) the axial velocity. * [PERSON] et al. (1997) [PERSON]; [PERSON]; [PERSON] Viscous Throughput Modelling of Transonic Compressors Using a Time-Marching Finite-Volume Solver. In Proceedings of the 13 th International Symposium on Airbreathing Engines (ISABE), Chattanooga, TN, USA, 7-12 September 1997. * [PERSON] and [PERSON] (2005) [PERSON]; [PERSON] A Throughflow Analysis Tool Based on the Navier-Stokes Equations. In Proceedings of the 6 th European Turbomachinery Conference, Lille, France, 7-11 March 2005. * [PERSON] and [PERSON] (1999) [PERSON]; [PERSON] _Shock Representation by Euler Throughflow Models and Comparison with Pitch-Averaged Navier-Stokes Solutions_; ISABE 99-7281; PN Publications: Florence, Italy, 1999. * [PERSON] (1992) [PERSON] Toward Improved Throughput Capability: The Use of Three Dimensional Viscous Flow Solvers in a Multistage Environment. _Trans. ASME J. Turbomach._**1992**, _114_, 8-17. [CrossRef]
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