An experimental study on turbulent non-premixed jet flames is presented with focus on CO 2 -diluted oxy-fuel combustion using a coflow burner. Measurements of local temperatures and concentrations of the main species CO 2 , O 2 , CO, N 2 , CH 4 , H 2 O and H 2 were achieved using the simultaneous line-imaged Raman/Rayleigh laser diagnostics setup at Sandia National Laboratories. Two series of flames burning mixtures of methane and hydrogen were investigated. In the first series, the hydrogen molar fraction in the fuel was varied from 37 to 55 %, with a constant jet exit Reynolds number Re Fuel of 15,000. In the second series the jet exit Reynolds number was varied from 12,000 to 18,000, while keeping 55 % H 2 molar fraction in the fuel. Besides local temperatures and concentrations, the results revealed insights on the behaviour of localized extinction in the near-field. It was observed that the degree of extinction increased as the hydrogen content in fuel was decreased and as the jet Reynolds number was increased. Based on the distribution of the temperature, a fully burning probability index able to quantify the degree of extinction along the streamwise coordinate was defined and applied to the present flame measurements. A comparison of measured conditional mean of mass fractions and laminar flame calculations underlined the significant level of differential diffusion in the near-field that tended to decrease farther downstream. The results also showed high local CO levels induced by the high content of CO 2 in the oxidizer and flame products. A shift of maximum flame temperature was observed toward the rich side of the mixture fraction space, most likely as a consequence of reduced heat release in the presence of product dissociation. Main characteristics of laser Raman scattering measurements in CO 2 -diluted oxy-fuel conditions compared to air-diluted conditions are also highlighted. Most data, including scalar fluctuations and conditional statistics are available upon request.

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Due to increased share of fluctuating renewable energy sources in future decarbonized, electricity-driven energy systems, participating in the electricity markets yields the potential for industry to reduce its energy costs and emissions. A key enabling technology is thermal energy storage combined with power-to-heat technologies, allowing the industries to shift their energy demands to periods with low electricity prices. This paper presents an optimization-based method which helps to select and dimension the cost-optimal thermal energy storage technology for a given industrial steam process. The storage technologies considered in this work are latent heat thermal energy storage, Ruths steam storage, molten salt storage and sensible concrete storage. Due to their individual advantages and disadvantages, the applicability of these storage technologies strongly depends on the process requirements. The proposed method is based on mathematical programming and simplified transient simulations and is demonstrated using different scenarios for energy prices, i.e., various types of renewable energy generation, and varying heat demand, e.g., due to batch operation or non-continuous production.

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