Computational fluid dynamics as a design tool for the hot gas manifold of the Space Shuttle Main Engine

In this paper, the use of computational fluid dynamics is evaluated as a design tool to investigate the indoor climate of a confined greenhouse. The finite volume method using polyhedral cells is used to solve the governing mass, momentum and energy equations. Natural convection in a cavity corresponding to a mono-span venlo-type greenhouse is numerically investigated using Computational Fluid Dynamics. The CFD model is designed so as to simulate the climate above a plant canopy in an actual multi-span greenhouse heated by solar radiation. The aim of this paper is to investigate the influence of various design parameters such as pitch angle and roof asymmetry and on the velocity and temperature patterns inside a confined single span greenhouse heated from below. In the study reported in this paper a two-dimensional CFD model was generated for the mono-span venlo-type greenhouse, and a mesh sensitivity analysis was conducted to determine the mesh independence of the solution. Similar two-dimensional flow patterns were observed in the obtained CFD results as the experimental results reported by Lamrani et al [2]. The CFD model was then modified and used to explore the effect of roof pitch angle and roof asymmetry at floor level on the development of the flow and temperature patterns inside the cavity for various Rayleigh numbers. Results are presented in the form of vector and contour plots. It was found that considerable temperature and velocity gradients were observed in the centre of the greenhouse for each case in the first 40mm above the ground, as well as in the last 24mm close to the roof. Results also indicated that the Rayleigh number did not have a significant impact on the flow and temperature patterns inside the greenhouse, although roof angle and asymmetry did. The current results demonstrate the importance of CFD as a design tool in the case of greenhouse design.

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Computational Fluid Dynamics: A Design Tool for Aircraft Industries

Lecture Notes in Mechanical Engineering - Innovative Design, Analysis and Development Practices in Aerospace and Automotive Engineering ◽

10.1007/978-81-322-1871-5_10 ◽

2014 ◽

pp. 65-66

Author(s):

P. Srinivasa Murthy

Keyword(s):

Fluid Dynamics ◽

Computational Fluid Dynamics ◽

Design Tool

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Flow mechanisms in axial turbine rim sealing

Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science ◽

10.1177/0954406218784612 ◽

2018 ◽

Vol 233 (23-24) ◽

pp. 7637-7657 ◽

Cited By ~ 5

Author(s):

John W Chew ◽

Feng Gao ◽

Donato M Palermo

Keyword(s):

Fluid Dynamics ◽

Computational Fluid Dynamics ◽

Experimental Studies ◽

Power Cycle ◽

Sealing Performance ◽

Flow Interactions ◽

Flow Mechanisms ◽

Flow Effects ◽

Main Engine ◽

Engine Power

This paper presents a review of research on turbine rim sealing with emphasis placed on the underlying flow physics and modelling capability. Rim seal flows play a crucial role in controlling engine disc temperatures but represent a loss from the main engine power cycle and are associated with spoiling losses in the turbine. Elementary models that rely on empirical validation and are currently used in design do not account for some of the known flow mechanisms, and prediction of sealing performance with computational fluid dynamics has proved challenging. Computational fluid dynamics and experimental studies have indicated important unsteady flow effects that explain some of the differences identified in comparing predicted and measure sealing effectiveness. This review reveals some consistency of investigations across a range of configurations, with inertial waves in the rotating flow apparently interacting with other flow mechanisms which include vane, blade and seal flow interactions; disc pumping and cavity flows; shear layer and other instabilities; and turbulent mixing.

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Aerodynamic evaluation of the redesigned Space Shuttle Main Engine hot-gas manifold

10.2514/6.1985-1386 ◽

1985 ◽

Cited By ~ 1

Author(s):

S. VOGT ◽

W. CUAN ◽

F. HOEHN ◽

B. KIM ◽

G. OCONNOR ◽

...

Keyword(s):

Space Shuttle ◽

Hot Gas ◽

Main Engine

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Computational Modelling of Self-Excited Combustion Instabilities

Volume 2: Coal, Biomass and Alternative Fuels; Combustion and Fuels; Oil and Gas Applications; Cycle Innovations ◽

10.1115/2000-gt-0104 ◽

2000 ◽

Cited By ~ 4

Author(s):

Steve J. Brookes ◽

R. Stewart Cant ◽

Iain D. J. Dupere ◽

Ann P. Dowling

Keyword(s):

Fluid Dynamics ◽

Computational Fluid Dynamics ◽

Heat Release ◽

Large Scale ◽

Computational Modelling ◽

Combustion Efficiency ◽

Design Tool ◽

Premixed Combustion ◽

Combustion Instabilities ◽

Combustion Systems

It is well known that lean premixed combustion systems potentially offer better emissions performance than conventional non-premixed designs. However, premixed combustion systems are more susceptible to combustion instabilities than non-premixed systems. Combustion instabilities (large-scale oscillations in heat release and pressure) have a deleterious effect on equipment, and also tend to decrease combustion efficiency. Designing out combustion instabilities is a difficult process and, particularly if many large-scale experiments are required, also very costly. Computational fluid dynamics (CFD) is now an established design tool in many areas of gas turbine design. However, its accuracy in the prediction of combustion instabilities is not yet proven. Unsteady heat release will generally be coupled to unsteady flow conditions within the combustor. In principle, computational fluid dynamics should be capable of modelling this coupled process. The present work assesses the ability of CFD to model self-excited combustion instabilities occurring within a model combustor. The accuracy of CFD in predicting both the onset and the nature of the instability is reported.

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Optimum Range Thermal Design With Computational Fluid Dynamics

Heat Transfer, Volume 1 ◽

10.1115/imece2003-43361 ◽

2003 ◽

Author(s):

Prabhat Tekriwal

Keyword(s):

Fluid Dynamics ◽

Computational Fluid Dynamics ◽

Consumer Preference ◽

Design Tool ◽

Thermal Design ◽

Good Design ◽

Optimum Range ◽

Consumer Safety ◽

Temperature Requirements ◽

Design Options

A typical cooking range design requires that UL temperature requirements be met on outside surfaces for consumer safety. Another important consumer preference is that the range oven cavity be large in capacity so that it provides more cooking flexibility to consumers. These two requirements are in conflict with each other from design standpoint. CFD (Computational Fluid Dynamics) has proven to be a good design tool in balancing these opposing requirements and providing a optimum design without having to experiment with several design options and prototyping. The width of the air-wash that is used to cool the cooking range door through natural convection has been optimized with the aid of computational fluid dynamics. Increasing the air-wash width helps reduce the door surface temperature up to certain point, beyond which no gains in temperature reduction are realized.

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