Blade cooling generator maintenance

Why do gas turbine blades need to be cooled?

Cooling of the blades enhances the power output and thermal efficiency using the steam injection method. Nearly 60% efficiency can be achieved by adopting different cooling methods. The selection of the working fluid for gas turbines is dependent on the cycle, scale, and, application.

Which rotor blade material is better for a gas turbine?

IN 738 was better as a first stage rotor blade material. Various assumptions made which may not have been applicable for the gas turbine under study. Manufacture and operate gas turbines with less chance of failure. Provide guidance for turbine maintenance to prevent failure. Sankar et al. 2019

How to determine the closeness of coolant & blade surface?

The closeness of coolant and blade surface is determined by the elevating density ratio which provides positive effects on film cooling effectiveness. There are different types of methods for the cooling of the leading edge of GT blade such as vortex cooling, impingement cooling and double vortex cooling .

What are the components of a generator cooling system?

Coolant System – Each generator application can have a different cooling system configuration. Below is a general list of components: • Coolant pump – Depending on engine size, belt or gear driven. Circulates coolant throughout cooling system. • Radiator – Can be single or twin radiator design.

Should turbine blades be serviced after crack initiation?

Turbine blades should not provide service upon the crack initiation in the substrates. The blade cooling system design must be as such that the thermal-gradients and the thermal-stresses are minimized at the airfoils. Visual investigation, Optical-microscopy, EDS, SEM, XRD (X-ray-diffraction), and XRF (X-ray-fluorescence).

Which blade materials are suitable for open cycle industrial gas turbines?

Salwan et al. reviewed various materials and their properties and composition to identify suitable blade materials for open cycle industrial gas turbines and concluded alloys such as CM 247 LC, Mar M247, PWA 148, and CMSX2 to be the most suited for blade constructions .