1. Heat Transfer Analysis
P08451: Thermoelectric Waste Heat Recovery From Large Scale Systems
Sponsored By:
Background
Scope
Develop a system model that can relate P07441 Automotive Exhaust Test Bed to Dresser-Rand VECTRA 40 Gas Turbine.
Use the model to design, build and test a modular, small scale prototype.
Verify and refine the analytical heat transfer model as necessary.
The Technology
In recent years, the cost of fuels has dramatically increased. With this, the world has become more concerned with the efficient use of energy. A large source of wasted heat occurs in turbo machinery located in an industrial setting. Some of these machines, as is the case with the Dresser Rand VECTRA 40 gas turbine, lose 60% of the energy input as waste heat expelled to the atmosphere. This project looks at the feasibility of using thermoelectric modules to recover energy from that waste heat, ultimately increasing system efficiency.
Thermoelectric Module
Solid-State device (no moving parts)
Uses the Seebeck Effect to generate power from a temperature gradient
Low efficiency in the 5% range. Novel materials research is increasing this efficiency and bringing attention to power generation aspects of this technology.
The Prototype
Heat Transfer Analysis
The above figure displays the predicted results of prototype power generation using the numerical model. A total of thirty geometrical, thermal, and flow condition parameters are required to compute temperature distributions, current and power generation, as well as module and system efficiency. This is accomplished through a Gauss-Seidel iterative process, making the assumption that heat loss from the exhaust within each respective zone is uniform, and neglecting any heat loss through the insulation of the side walls.
Dresser-Rand VECTRA 40 Gas Turbine
Feasibility Analysis
A modular prototype was designed to enable various test configurations used in verification of the analytical heat transfer model. The number and type of TE modules, geometry of the fins and exhaust flow rates are all variable. The prototype is broken into three distinct regions to mitigate isothermal effects and provide insight on how temperature changes down the length of the duct.
The above figure displays the projected results of cost per kilo-watt hour for a hypothetical, industrial, thermo-electric waste heat recovery system. The feasibility model allows for the adjustment of the module figure of merit and the number of modules incorporated in the system by altering the number of modules in a particular zone as well as the total number of zones.
Special Thanks to:
Paul Chillcott (Dresser-Rand)
Dave Hathaway (RIT ME)
Steven Kosciol (RIT ME)
Robert Kraynik (RIT ME)
Kevin Smith (RIT ME Grad Student)
Emil Sandoz-Rosado (RIT ME Grad Student)
Mahany Welding Supply
Team P08451
Sample Results