EFFIZIENTE INDUSTRIEPROZESSE DURCH ABWÄRMENUTZUNG MITTELS HOCHTEMPERATUR-WÄRMEPUMPEN

Überblick zum DLR-Institut für CO2-arme Industrieprozesse sowie einen detaillierten Einblick in die Abteilung für Hochtemperaturwärmepumpen. Inhaltlich geht es um die Prozessintegration der Hochtemperatur-Wärmepumpe und Abwärme als Quelle

INDUSTRIEPROZESSE MITTELS HOCHTEMPERATUR-WÄRMEPUMPEN EFFIZIENT DEKARBONISIEREN

Vorstellung DLR Institut für CO2- arme Industrieprozesse und deren Aufgabengebiete: Hochtemperatur- Wärmepumpen und deren Prozessintegratio

The Potential of Casing Treatments for Transonic Compressors: Evaluation Based on Axial-Slot and Rotor Blade Optimization

Casing treatments (CTs) have proven their potential to increase the working range of a compressor stage, sometimes even with little or no decrease in efficiency. However, a positive impact on efficiency is only possible if the additional CT-losses are compensated by a reduction of other losses, especially at rotor tip. This appears to be increasingly difficult to achieve for highly efficient modern rotors. In order to analyse how CTs can contribute to improve the overall compressor design, extensive optimization studies are performed, aiming at increasing the stability and efficiency of a transonic compressor stage. Axial-slot CTs and the rotor are optimized separately with a high number of geometric parameters. Selected Pareto-optimal geometries of the two optimizations are combined to study various CTs on different rotors. It is shown that a significant increase in stability can be achieved using axial-slot CTs, exceeding the values that can be reached optimizing the rotor without CTs. However, no combination of optimized rotors and CTs is found that dominates the other geometries in terms of efficiency. Hence, the question whether a CT can contribute to an improved compressor design very much depends on the desired stage design. CTs provide a benefit if a maximum stability range is necessary or if certain design choices lead to a demand for a stability enhancement, that otherwise cannot be achieved. In order to gain a maximum efficiency, a design without CTs appears to be more promising in the first place. Designs with comparably high losses in the rotor tip region, e.g. due to large tip clearances, might also benefit of CTs in terms of efficiency

Design Optimization of a Multi-Stage Axial Compressor Using Throughflow and a Database of Optimal Airfoils

The basic tool set to design multi-stage axial compressors consists of fast codes for throughflow and blade-to-blade analysis. Detailed blade row design is conducted with 3D CFD, mainly to control the end wall flow. This work focuses on the interaction between throughflow and blade-to-blade design and the transition to 3D CFD. A design strategy is presented that is based on a versatile airfoil family. The new class of airfoils is generated by optimizing a large number of airfoil shapes for varying design requirements. Each airfoil geometry satisfies the need for a wide working range as well as low losses. Based on this data, machine learning is applied to estimate optimal airfoil shape and performance. The performance prediction is incorporated into the throughflow code. Based on a throughflow design, the airfoils can be stacked automatically to generate 3D blades. On this basis, a 3D CFD setup can be derived. This strategy is applied to study upgrade options for a 15-stage stationary gas turbine compressor test rig. At first, the behavior of the new airfoils is studied in detail. Afterwards, the design is optimized for mass flow rate as well as efficiency. Selected configurations from the Pareto-front are evaluated with 3D CFD

Thermodynamic analysis of an industrial process integration of a reversed Brayton high-temperature heat pump: A case study of an industrial food process

Industry, as a major emitter of CO2 in the process heat sector in Europe, needs to switch from fossil fuels to renewable energy for heat supply. High temperature heat pumps (HTHP) can electrify process heat and integrate renewable electricity into industrial processes. The Institute of Low-Carbon Industrial Processes of the German Aerospace Center (DLR) is developing HTHPs based on the reversed Brayton and Rankine cycles for delivery temperatures above 150°C and is investigating the industrial process integration of this novel technology. The current study considers different integration strategies of a reversed Brayton HTHP in a food production process with a heat sink at 250 °C. A thermodynamic analysis evaluates the results. This study allows conclusions to be drawn about the process integration of Brayton HTHPs in industrial food processes or other industrial processes with heat sinks around 250 °C

Investigation on Process Architectures for High-Temperature Heat Pumps Based on a Reversed Brayton Cycle

Heat pumps are a core technology for the decarbonization of industrial process heat. High-temperature heat pumps (HTHP) typically upgrade waste heat of industrial processes. This way they can simultaneously electrify process heat and reduce the respective primary energy consumption. The utilization of renewable electricity to drive HTHP additionally results in decarbonization of process heat supply. Commercial industrial heat pumps supply process heat at temperatures up to approximately 150°C. However, several studies have shown that process heat can be also supplied with HTHP at temperatures above 150°C. The economic and environmental performance of HTHPs depend strongly on their process architecture and their integration into the industrial process they supply with heat. This paper focuses on the investigation of high-temperature heat pump process architectures based on the reversed Brayton cycle with air as the working medium. The process architecture of the HTHP pilot plant at the Institute of Low-Carbon Industrial Processes of the German Aerospace Center (DLR) is presented and used as a reference. The current work investigates the heat source and heat sink integration in the heat pump cycle architecture and methods to effectively break down the compression and expansion processes to optimize performance for a heat sink temperature of 250°C. To analyze and compare the results, fixed boundary conditions valid for all architectures are made

Entwicklung einer Rankine-basierten Hochtemperatur- Wärmepumpe für die industrielle Nutzung

Der Beitrag beinhaltet eine Analyse hinsichtlich des Temperatur- und Wärmebedarfs der Wirtschaftszweige in der Prozesswärme. Der Schwerpunkt des Beitrages ist die Vorstellung des Konzeptes der Hochtemperatur-Wärmepumpe mit der Anlage "Pilot-ZiRa", welche auf dem Rankine-Prozess basiert und im DLR-DI (Standort Zittau) für industrielle Nutzung entwickelt wurde

Thermodynamic analysis of an industrial process integration of a reversed Brayton high-temperature heat pump: A case study of an industrial food process

Industry, as a major emitter of CO2 in the process heat sector in Europe, needs to switch from fossil fuels to renewable energy for heat supply. High temperature heat pumps (HTHP) can electrify process heat and integrate renewable electricity into industrial processes. The Institute of Low-Carbon Industrial Processes of the German Aerospace Center (DLR) is developing HTHPs based on the reversed Brayton and Rankine cycles for delivery temperatures above 150°C and is investigating the industrial process integration of this novel technology. The current study considers different integration strategies of a reversed Brayton HTHP in a food production process with a heat sink at 250 °C. A thermodynamic analysis evaluates the results. This study allows conclusions to be drawn about the process integration of Brayton HTHPs in industrial food processes or other industrial processes with heat sinks around 250 °C