Effects of Coolant Feed Direction on Additively Manufactured Film Cooling Holes

Stimpson, Curtis K.; Snyder, Jacob C.; Thole, Karen A.; Mongillo, Dominic

doi:10.1115/1.4041374

Cited by 21 publications

(6 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In addition to internal cooling, film cooling holes produced with AM have also begun to be studied in the literature. Studies by Schulz and Behrendt [16] and Vinton et al [17] utilized AM to study different effusion cooling designs, while studies by the current authors investigated the impact of AM roughness on the performance of a single row of shaped film cooling holes [6,18]. While there have been some studies showing the effect of in-hole roughness on the film effectiveness [19], the extent to which the AM parameters can affect the performance of an AM hole has yet to be explored.…”

Section: Literature Reviewmentioning

confidence: 98%

See 1 more Smart Citation

Effect of Additive Manufacturing Process Parameters on Turbine Cooling

Snyder

Thole

2020

Journal of Turbomachinery

Self Cite

View full text Add to dashboard Cite

Turbine cooling is a prime application for additive manufacturing because it enables quick development and implementation of innovative designs optimized for efficient heat removal, especially at the micro-scale. At the micro-scale, however, the surface finish plays a significant role in the heat transfer and pressure loss of any cooling design. Previous research on additively manufactured cooling channels has shown surface roughness increases both heat transfer and pressure loss to similar levels as highly engineered turbine cooling schemes. What has not been shown, however, is whether opportunities exist to tailor additively manufactured surfaces through control of the process parameters to further enhance the desired heat transfer and pressure loss characteristics. The results presented in this paper uniquely show the potential of manipulating the parameters within the additive manufacturing process to control the surface morphology, directly influencing turbine cooling. To determine the effect of parameters on cooling performance, coupons were additively manufactured for common internal and external cooling methods using different laser powers, scan speeds, and scanning strategies. Internal and external cooling tests were performed at engine relevant conditions to measure appropriate metrics of performance. Results showed the process parameters have a significant impact on the surface morphology leading to differences in cooling performance. Specifically, internal and external cooling geometries react differently to changes in parameters, highlighting the opportunity to consider process parameters when implementing additive manufacturing for turbine cooling applications.

show abstract

Section: Literature Reviewmentioning

confidence: 98%

“…By holding the relevant non-dimensional parameters in Eq. (2) constant, the augmented effectiveness provides an idea of the film effectiveness without directly measuring it [18].…”

Section: Process Effects On Cooling Performancementioning

confidence: 99%

Effect of Additive Manufacturing Process Parameters on Turbine Cooling

Snyder

Thole

2020

Journal of Turbomachinery

Self Cite

View full text Add to dashboard Cite

show abstract

“…In laboratory condition, several researchers have conditioned the value of Biot number selecting a different material for the test plate or acting on the scale dimensions [17]. The recent interest of scientific research on heat transfer is moving toward additive manufacturing components at 1:1 scale in order to take into account effects of additive manufacturing [18]. For this reason the scale 1:1 and the use of engine materials become constrains of the test rig design, limiting the possibility of perfectly match the non dimensional parameters cited above.…”

Section: Dimensional Analysismentioning

confidence: 99%

A New Test Facility for Investigating Thermal Behaviour of Effusion Cooling Test Plates for RQL Combustors

Picchi

Andreini

Becchi

et al. 2020

Volume 7A: Heat Transfer

View full text Add to dashboard Cite

In aero engines the combustors are subjected to critical thermal conditions in terms of high temperatures and corrosive environment, which could affect the service life of the entire system. As well known, Thermal Barrier Coatings (TBC) and above all cooling systems represents the state-of-the-art in the nowadays protecting methods: the maximization of this beneficial effect is achieved by defining an optimal cooling arrangement and developing suitable manufacturing technologies for these systems. In modern aero-engine combustors, one of the most effective cooling scheme for liners is composed by an effusion perforation coupled with a slot system to start the film cooling. The cooling performances are deeply influenced by the mutual interactions between swirling and cooling flows. In addition, for typical Rich-Quench-Lean (RQL) combustor architectures, the injection of air provided to promoting the local break-down of the flame mixture fraction, deeply interacts with the swirled flow, generating recirculating structures capable of affecting the development of film cooling and making the design of cooling systems very challenging. A new test facility for testing effusion test plates for RQL combustors applications has been developed with the final aim of comparing different cooling strategies and at the same time to collect data for numerical model validation. The experimental set-up consists of a non-reactive planar sector rigs with 5 engine-scale swirlers fed with air up to 250 °C and 3 bar. The rig was equipped with outer/inner dilution ports, and a simple inner liner cooling scheme composed of effusion and a slot system: all these features, fed with air at ambient temperature, can be independently controlled in terms of mass flow. Using dedicated optical accesses, InfraRed (IR) camera tests were performed to retrieve overall effectiveness data imposing a temperature difference between swirling and cooling flows. To better understand those results, Pressure Sensitive Paint (PSP) technique was used to obtain reliable film effectiveness data decoupling the contribution of slot and effusion flows. The thermal characterization was supported by Particle Image Velocimetry (PIV) investigations on the median plane. Tests were performed at different pressure drops across swirler and varying the mass flows of slot and inner/outer liners. The analysis of the data highlighted the influences of the swirling flow on the overall thermal performance and the behaviour of the film cooling system.

show abstract

“…The test articles were manufactured in Inconel material using laser sintering technology and it was externally machined to restore an adequate finishing of the vane profile. The shaped holes were realized using standard EDM procedure which guarantee high fidelity of the internal hole geometry [15].…”

Section: Cascade Test Rigmentioning

confidence: 99%

Flat Plate and Turbine Vane Film-Cooling Performance with Laid-Back Fan-Shaped Holes

Bacci

Picchi

Facchini

2019

IJTPP

View full text Add to dashboard Cite

Shaped holes are considered as an effective solution to enhance gas turbine film-cooling performance, as they allow to increase the coolant mass-flux, while limiting the detrimental lift-off phenomena. A great amount of work has been carried out in past years on basic flat plate configurations while a reduced number of experimental works deals with a quantitative assessment of the influence of curvature and vane pressure gradient. In the present work PSP (Pressure Sensitive Paint) technique is used to detail the adiabatic effectiveness generated by axial shaped holes with high value of Area Ratio close to 7, in three different configurations with the same 1:1 scale: first of all, a flat plate configuration is examined; after that, the film-cooled pressure and suction sides of a turbine vane model are investigated. Tests were performed varying the blowing ratio and imposing a density ratio of 2.5. The experimental results are finally compared to the predictions of two different correlations, developed for flat plate configurations.

show abstract

Effects of Coolant Feed Direction on Additively Manufactured Film Cooling Holes

Cited by 21 publications

References 25 publications

Effect of Additive Manufacturing Process Parameters on Turbine Cooling

Effect of Additive Manufacturing Process Parameters on Turbine Cooling

A New Test Facility for Investigating Thermal Behaviour of Effusion Cooling Test Plates for RQL Combustors

Flat Plate and Turbine Vane Film-Cooling Performance with Laid-Back Fan-Shaped Holes

Contact Info

Product

Resources

About