Waste heat recovery from power plants and industries requires a new type of electricity generator and related technological developments. The current research work is aimed at the design of a multi-kilowatt thermoacoustic electric generator, which can be employed as the bottoming cycle of a gas-turbine power plant or for industrial waste heat recovery. The proposed device converts thermal energy into acoustic power and subsequently uses a piezoelectric alternator to convert acoustic power into electricity. The challenge in designing such a device is that it has to be acoustically balanced. The performance of the device is greatly affected by numerous parameters such as frequency of the traveling acoustic wave, heat exchanger parameters, regenerator dimensions, acoustic feedback loop, etc. The proposed device is a lab-scale demonstration targeted to produce few kilowatts of electric power from a 20 kWth heat source. DeltaEC software is used to achieve the acoustically balanced configuration of the device. The DeltaEC model outcomes are used to arrive at the optimized design of the device and its components. The analytical method, the optimized geometrical dimensions of thermoacoustic components, and the minimum required conditions of heat source input are presented in this paper.

Waste heat recovery from power plants and industries requires a new type of electricity generators and related technological developments. The current research work is aimedat the design of a multi-kilowatt thermoacoustic electric generator, which can be employed as the bottoming cycle of a gas-turbine power plant or for industrial waste heat recovery. The proposed device converts thermal energy into acoustic power and subsequently uses a piezoelectric alternator to convert acoustic power into electricity. The challenge in designing such a device is that it has to be acoustically balanced and the performance of the device is greatly affected by numerous parameters such as frequency of the traveling acoustic wave, heat exchanger parameters, regenerator dimensions, acoustic feedback loop, etc. The proposed device is a lab-scale demonstration targeted to produce a few kilowatts of electric power from a 20 kWth heat source. To achieve the acoustically balanced configuration of the device, DeltaEC software is used. The DeltaEC model outcomes are used to arrive at the optimized design of the device and its components. The analytical method, the optimized geometrical dimensions of thermoacoustic components and the minimum required conditions of heat source input are presented in this paper.

Waste heat recovery from power plants and industries requires a new type of electricity generators and related technological developments. The current research work is aimed at the design of a multi-kilowatt thermoacoustic electric generator, which can be employed as the bottoming cycle of a gas-turbine power plant or for industrial waste heat recovery. The proposed device converts thermal energy into acoustic power and subsequently uses a piezoelectric alternator to convert acoustic power into electricity. The challenge in designing such a device is that it has to be acoustically balanced and the performance of the device is greatly affected by numerous parameters such as frequency of the traveling acoustic wave, heat exchanger parameters, regenerator dimensions, acoustic feedback loop, etc. The proposed device is a lab-scale demonstration targeted to produce a few kilowatts of electric power from a 20 kWth heat source. To achieve the acoustically balanced configuration of the device, DeltaEC software is used. The DeltaEC model outcomes are used to arrive at the optimized design of the device and its components. The analytical method, the optimized geometrical dimensions of thermoacoustic components and the minimum required conditions of heat source input are presented in this paper.

Thermoacoustics (TA) engines and refrigerators typically run on the Stirling cycle with acoustic networks and resonators replacing the physical pistons. Without moving parts, these TA machines achieve a reasonable fraction of Carnot’s efficiency. They are also scalable, from fractions of a Watt up to kW of cooling. Despite their apparent promise, TA devices are not in widespread use, because outside of a few niche applications, their advantages are not quite compelling enough to dislodge established technology. In the present study, the authors have evaluated a selected group of applications that appear suitable for utilization of industrial waste heat using TA devices and have arrived at a ranked order. The principal thought is to appraise whether thermoacoustics can be a viable path, from both an economic and energy standpoint, for carbon mitigation in those applications. The applications considered include cryogenic carbon capture for power plant exhaust gases, waste-heat powered air conditioning/water chilling for factories and office buildings, hydrogen liquefaction, and zero-boiloff liquid hydrogen (LH2) storage. Although the criteria used for evaluating the applications are somewhat subjective, the overall approach has been consistent, with the same set of criteria applied to each of them. Thermoeconomic analysis is performed to evaluate the system viability, together with overall consideration of a thermoacoustic device’s general nature, advantages, and limitations. Our study convincingly demonstrates that the most promising application is zero-boiloff liquid hydrogen storage, which is physically well-suited to thermoacoustic refrigeration and requires cooling at a temperature and magnitude not ideal for standard refrigeration methods. Waste-heat powered air conditioning ranks next in its potential to be a viable commercial application. The rest of the applications have been found to have relatively lower potentials to enter the existing commercial space.