Using a sophisticated computer code, the design and analysis of steam turbine flow path or individual stages, evaluation of proposed unit upgrades and load range changes, or analysis of units being considered for repowering to a combined cycle unit is provided.

Suitable for fossil, nuclear, and industrial units and applicable to all geometric turbine stage configurations including: Rateau and Curtis Control Stages, impulse and reaction HP, IP, and LP staging, including the long last row LP blades, and multiple steam inlets, such as in combined cycle units.

Turbine mass flow rate for a given geometry and bounding steam conditions

The effects of rotor blade and stator vane surface finish (roughness) as a function of local blade path flow conditions

The effects of moisture removal on turbine performance; primarily applicable to nuclear LPs

The computer model is based on a multi-stream tube approach to flow field design and analysis, i.e., axi-symmetric (2 dimensional). It assumes a simplified radial equilibrium at stator exit (with streamline curvature option) and conservation of angular momentum between stator exit and rotor inlet (mass flows may be different).

The program has the following customizations that allow modeling of most flow phenomena:

Very low flow rates can be accommodated - down to no load flow. Blade flow reversal regions are determined wherein affected stages may act as a compressor delivering energy to the blade path flow

All seal discharge coefficients are determined internally, the number of seals is arbitrary, 1 to >40, they may be straight through or stepped

The Rateau axial seal and disc balance hole discharge coefficients are also determined internally

Seal leakage and flow directions can reverse due to the effects of negative reaction or very low flow rates

The control stage and Rateau stages can be partially admitted; Curtis stage admissions can be different

Inlet steam conditions can be maintained at prescribed levels, such as consistent with given throttle conditions and inlet pressure loss characteristics

The turbine's exhaust pressure may be held constant or may be determined as a function of a pressure-flow curve or by means of a defined flow number

Interstage total pressure losses can be defined, such as those due to piping losses

Several blade loss options are available including a design loss model, secondary flow losses, and incidence losses

A maximum of three feedwater heaters can be accommodated, two closed heaters with or without drain coolers, and one deaerator

Converging-diverging blade passages can be incorporated in the last rotor blade

Inquiries as to the application and/or lease of this Steam Turbine Design and Analysis Computer Program can be made to the program's developer (Turboflow International, Inc.) through Jonas, Inc.