# 物理代写|流体力学代写Fluid Mechanics代考|AMME2261

## 物理代写|流体力学代写Fluid Mechanics代考|Theory of Thermal Turbomachinery Stages

Turbomachines are devices within which conversion of total energy of a working medium into mechanical energy and vice-versa takes place. Turbomachines are generally divided into two main categories. The first category is used primarily to produce power. It includes, among others, steam turbines, gas turbines, and hydraulic turbines. The main function of the second category is to increase the total pressure of the working fluid by consuming power. It includes compressors, pumps, and fans. Gas turbines are also used for thrust generation and utilized in small aircrafts as propeller gas turbines and as high performance jet engines in medium and large size civil and military aircrafts. While the power generation gas turbines have a single spool with a multi-stage compressor, a combustion chamber and a multi-stage turbine, the aircraft engines may have up to three-spools that rotate at different frequency. The turbine component of gas and steam turbines are of axial type design, the compressor may be of axial or radial design, depending on their required mass flow. For small scale gas turbines, the application of radial compressors is more common than the axial ones. This is also true for the turbine component of turbochargers. The subject of turbomachinery aero-thermodynamic design is treated, among others, in [20-22].

## 物理代写|流体力学代写Fluid Mechanics代考|Energy Transfer in Turbomachinery Stages

The energy transfer in turbomachinery is established by means of the stages. A turbomachinery stage comprises a row of fixed guide vanes called stator blades, and a row of rotating blades termed rotor. To elevate the total pressure of a working fluid, compressor stages are used that partially convert the mechanical energy into potential energy. According to the conservation law of energy, this energy increase requires an external energy input which must be added to the system in the form of mechanical energy. Figure 5.17a, b schematically represent two single stages within a multi-stage high pressure turbine and a high pressure compressor environment with constant mean diameter. These stages consist of one stator row followed by one rotor row. To define a unified station nomenclature for compressor and turbine stages, we identify with station number 1 as the inlet of the stator, followed by station 2 as the rotor inlet and 3, rotor exit. The absolute and relative flow angles are counted counterclockwise from a horizontal line. This convention allows an easier calculation of the off-design behavior of compressor and turbine stages during a transient operation.

The working fluid enters the stator row with an absolute velocity vector $V_1$ and an absolute inlet flow angle $\alpha_1$. It is deflected and exits the stator row at an exit flow angle $\alpha_2$ in direction of the rotor’s leading edge. The expansion process through the turbine stage, Fig. 5.18a, in connection with the rotational motion of the rotor causes a major portion of the total energy of the working medium to convert into the shaft power. Conversely, in the compressor stage shown in Fig. 5.18b, the compression process converts a major part of the mechanical energy input into the potential energy causing the total pressure to rise. In general, the compression process resulting in a decrease of specific volume requires a decrease in flow path cross sectional area. In contrast, the expansion process in a multi-stage turbine causes a continuous increase in specific volume which requires an increase in flow path cross section, Fig. 5.18.

## 物理代写|流体力学代写Fluid Mechanics代考|Energy Transfer in Turbomachinery Stages

myassignments-help数学代考价格说明

1、客户需提供物理代考的网址，相关账户，以及课程名称，Textbook等相关资料~客服会根据作业数量和持续时间给您定价~使收费透明，让您清楚的知道您的钱花在什么地方。

2、数学代写一般每篇报价约为600—1000rmb，费用根据持续时间、周作业量、成绩要求有所浮动(持续时间越长约便宜、周作业量越多约贵、成绩要求越高越贵)，报价后价格觉得合适，可以先付一周的款，我们帮你试做，满意后再继续，遇到Fail全额退款。

3、myassignments-help公司所有MATH作业代写服务支持付半款，全款，周付款，周付款一方面方便大家查阅自己的分数，一方面也方便大家资金周转，注意:每周固定周一时先预付下周的定金，不付定金不予继续做。物理代写一次性付清打9.5折。

Math作业代写、数学代写常见问题

myassignments-help擅长领域包含但不是全部: