Flow and thermal analyses of supercritical hydrocarbon fuel in curved regenerative cooling channel around cavity in rocket based combined cycle engine

An idea of using dimples as heat transfer enhancement device in a regenerative cooling passage is proposed to extend the cooling limits for liquid-propellant rocket and scramjet. Numerical studies have been conducted to investigate the flow and heat transfer characteristics of supercritical hydrocarbon fuel in a rectangular cooling channel with dimples applied to the bottom wall. The numerical model is validated through experimental data and accounts for real fuel properties at supercritical pressures. The study shows that the dimples can significantly enhance the convective heat transfer and reduce the heated wall temperature. The average heat transfer rate of the dimpled channel is 1.64 times higher than that of its smooth counterpart while the pressure drop in the dimpled channel is only 1.33 times higher than that of the smooth channel. Furthermore, the thermal stratification in a regenerative cooling channel is alleviated by using dimples. Although heat transfer deterioration of supercritical fluid flow in the trans-critical region cannot be eliminated in the dimpled channel, it can be postponed and greatly weakened. The strong variations of fuel properties are responsible for the local acceleration of fuel and variation of heat transfer performance along the cooling channel.

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Effect of Dimple Depth-Diameter Ratio on the Flow and Heat Transfer Characteristics of Supercritical Hydrocarbon Fuel in Regenerative Cooling Channel

International Journal of Aerospace Engineering ◽

10.1155/2021/7694510 ◽

2021 ◽

Vol 2021 ◽

pp. 1-9

Author(s):

Lihan Li ◽

Xin Li ◽

Jiang Qin ◽

Silong Zhang ◽

Wen Bao

Keyword(s):

Heat Transfer ◽

Pressure Loss ◽

Hydrocarbon Fuel ◽

Diameter Ratio ◽

Fluid Temperature ◽

Cooling Channel ◽

Heat Transfer Characteristics ◽

Regenerative Cooling ◽

Transfer Characteristics ◽

Flow And Heat Transfer

In order to extend the cooling capacity of thermal protection in various advanced propulsion systems, dimple as an effective heat transfer enhancement device with low-pressure loss has been proposed in regenerative cooling channels of a scramjet. In this paper, numerical simulation is conducted to investigate the effect of the dimple depth-diameter ratio on the flow and heat transfer characteristics of supercritical hydrocarbon fuel inside the cooling channel. The thermal performance factor is adopted to evaluate the local synthetically heat transfer. The results show that increasing the dimple depth-diameter ratio h / d p can significantly reduce wall temperature and enhance the heat transfer inside the cooling channel but simultaneously increase pressure loss. The reason is that when h / d p is rising, the recirculation zones inside dimples would be enlarged and the reattachment point is moving downstream, which enlarge both the high Nu area at rear edge of dimple and the low Nu area in dimple front. In addition, when fluid temperature is nearer the fluid pseudocritical temperature, local acceleration caused by dramatic fluid property change would reduce the increment of heat transfer and also reduce pressure loss. In this study, the optimal depth-diameter ratio of dimple in regenerative cooling channel of hydrocarbon fueled is 0.2.

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Pyrolysis and coking of endothermic hydrocarbon fuel in regenerative cooling channel under different pressures

Journal of Analytical and Applied Pyrolysis ◽

10.1016/j.jaap.2017.04.010 ◽

2017 ◽

Vol 125 ◽

pp. 117-126 ◽

Cited By ~ 30

Author(s):

Baitang Jin ◽

Kai Jing ◽

Jie Liu ◽

Xiangwen Zhang ◽

Guozhu Liu

Keyword(s):

Hydrocarbon Fuel ◽

Cooling Channel ◽

Regenerative Cooling ◽

Endothermic Hydrocarbon Fuel

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Evaluation Model for Fast Convective Heat Transfer Characteristics of Thermal Cracked Hydrocarbon Fuel Regenerative Cooling Channel in Hydrocarbon-Fueled Scramjet

Applied Thermal Engineering ◽

10.1016/j.applthermaleng.2021.117616 ◽

2021 ◽

Vol 199 ◽

pp. 117616

Author(s):

Qing Xu ◽

Guowei Lin ◽

Haowei Li

Keyword(s):

Heat Transfer ◽

Convective Heat Transfer ◽

Convective Heat ◽

Evaluation Model ◽

Hydrocarbon Fuel ◽

Cooling Channel ◽

Heat Transfer Characteristics ◽

Regenerative Cooling ◽

Transfer Characteristics

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Numerical Investigation on Heat Transfer and Oxidation Deposition of Aviation Fuel in a Rotatory U-Channel

Journal of Turbomachinery ◽

10.1115/1.4049610 ◽

2021 ◽

Vol 143 (2) ◽

Author(s):

Zekun Zheng ◽

Xinyan Pei ◽

Siqian Yan ◽

Lingyun Hou

Keyword(s):

Heat Transfer ◽

Deposition Rate ◽

Turbulent Transport ◽

Hydrocarbon Fuel ◽

Deposition Process ◽

Outer Edge ◽

Aviation Fuel ◽

Regenerative Cooling ◽

Turbine Cooling ◽

Rotation Numbers

Abstract Liquid-fuel regenerative cooling is a promising turbine cooling technology. We developed a numerical model of heat transfer coupled with oxidation deposition in a rotatory channel for regenerative cooling applications. Source terms for the centrifugal and Coriolis forces caused by rotation were added to the momentum equations and turbulent transport equations. A kinetic model for the thermal oxidation and deposition of supercritical hydrocarbon fuel was used to predict the oxidation deposition process. Coupled fluid–solid simulations of the heat transfer and oxidation deposition of hydrocarbon fuel in a U-shaped channel at five rotation numbers showed that the rotation improves convective heat transfer in the cooling channel and prevents the occurrence of a heat transfer deterioration zone. The average deposition rate in the channel decreased with increasing rotation number. In the centrifugal section of the rotatory channel, the Coriolis force caused the temperatures of the leading wall to be higher than those of the trailing wall, but the differences became smaller and nearly disappeared in the elbow and centripetal sections. The deposition rate on the leading wall was higher than that on the trailing wall in the straight centrifugal channel. In the bending section, the oxidation deposits were more prone to form on the inner edge than on the outer edge.

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The Elephant in the Room–Gas Turbine Power

Mechanical Engineering ◽

10.1115/1.2010-dec-8 ◽

2010 ◽

Vol 132 (12) ◽

pp. 57-57

Author(s):

Lee S. Langston

Keyword(s):

Power Plant ◽

Electric Power ◽

Gas Turbine ◽

Power Plants ◽

Electrical Power ◽

Electric Power Industry ◽

Hydrocarbon Fuel ◽

Combined Cycle ◽

Electrical Generator ◽

Gas Turbine Exhaust

This article presents an overview of gas turbine combined cycle (CCGT) power plants. Modern CCGT power plants are producing electric power as high as half a gigawatt with thermal efficiencies approaching the 60% mark. In a CCGT power plant, the gas turbine is the key player, driving an electrical generator. Heat from the hot gas turbine exhaust is recovered in a heat recovery steam generator, to generate steam, which drives a steam turbine to generate more electrical power. Thus, it is a combined power plant burning one unit of fuel to supply two sources of electrical power. Most of these CCGT plants burn natural gas, which has the lowest carbon content of any other hydrocarbon fuel. Their near 60% thermal efficiencies lower fuel costs by almost half compared to other gas-fired power plants. Their installed capital cost is the lowest in the electric power industry. Moreover, environmental permits, necessary for new plant construction, are much easier to obtain for CCGT power plants.

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