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Article
Publication date: 1 February 2009

Qingmao Zhang and Guansheng Li

This study reviews the application of the C/SiC composites in the thermal protection systems (TPS). Special attention is put on the structure design and optimization of the C/SiC…

588

Abstract

This study reviews the application of the C/SiC composites in the thermal protection systems (TPS). Special attention is put on the structure design and optimization of the C/SiC shell panel. The comparisons of several TPS show that the ceramic matrix composite (CMC) is one of the most potential materials for TPS. The crucial role of multi‐disciplinary design and optimization is pointed out in the future design of C/SiC thermal protection structure. This review provides a guideline on the current and future study of C/SiC thermal protection structure.

Details

Multidiscipline Modeling in Materials and Structures, vol. 5 no. 2
Type: Research Article
ISSN: 1573-6105

Keywords

Article
Publication date: 23 December 2020

Łukasz Brodzik

Paper aims to present problem of aerodynamic heating of a metallic heat shield. The key elements of this construction are metallic layers of superalloy honeycomb, which…

Abstract

Purpose

Paper aims to present problem of aerodynamic heating of a metallic heat shield. The key elements of this construction are metallic layers of superalloy honeycomb, which significantly increase the structure’s resistance to impact. Paper describes the problem of influence of damage size on increase of thermal load.

Design/methodology/approach

Numerical analysis was performed in a non-commercial environment FreeFem++ using finite element method, and its results were compared with the results given in the literature.

Findings

In thermal protection system, a modification was used to delay increase in temperature on the underlying structure as well as to reduce its maximum value.

Originality/value

In the further part of the paper, selected insulation material was modified by adding additional conductive material.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 31 no. 5
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 1 January 2007

M. Grujicic, C.L. Zhao, S.B. Biggers, J.M. Kennedy and D.R. Morgan

Common Aero Vehicles (CAVs) are relatively small‐size, un‐powered, self‐maneuvering vehicles equipped with a variety of weapons and launched from space. One of the major obstacles…

Abstract

Common Aero Vehicles (CAVs) are relatively small‐size, un‐powered, self‐maneuvering vehicles equipped with a variety of weapons and launched from space. One of the major obstacles hampering a full the realization of the CAV concept is a present lack of lightweight, high‐temperature insulation materials which can be used for construction of the CAV’s thermal protection system (TPS). A computational analysis is utilized in the present work to examine the suitability of a carbon‐based, coal‐derived foam for the TPS applications in the CAVs. Toward that end, a model is developed for the high‐temperature effective thermal conductivity of foam‐like materials. In addition, an insulation sizing procedure is devised to determine the minimum insulation thickness needed for thermal protection of the vehicle structure at different sections of a CAV. It is found that the carbon‐based foam material in question can be considered as a suitable TPS insulation material at the leeward side and at selected portions of the windward side of a CAV (specifically the portions which are further away from the vehicle nose).

Details

Multidiscipline Modeling in Materials and Structures, vol. 3 no. 1
Type: Research Article
ISSN: 1573-6105

Keywords

Article
Publication date: 1 February 2005

M.S. Domack and J.M. Baughman

Three layer‐additive manufacturing methods were evaluated to producing nickel‐titanium graded composition material. One potential application is fabrication of attachment clips…

9375

Abstract

Purpose

Three layer‐additive manufacturing methods were evaluated to producing nickel‐titanium graded composition material. One potential application is fabrication of attachment clips that join thermal protection systems to launch vehicle structure. Thermal gradients during flight generate excessive bending and shear loads that limit the service lifetime of the Inconel clips currently used. It is envisioned that a graded composition component could be tailored to reduce the stress concentrations.

Design/methodology/approach

Deposits with nearly continuous composition grade were built from Ti‐6‐4 and Inconel 718 powder using laser direct metal deposition. Layered deposits were produced by flat wire welding from Ti‐6‐4 and Inconel 718 wire. Ultrasonic consolidation was used to produce layered deposits from pure nickel and commercially pure titanium foils. Microstructure, bond line morphology, chemical composition, and reaction phases were characterized.

Findings

All three manufacturing methods require further development before graded composition material can be reliably produced. Laser direct metal deposition samples exhibited coarse dendritic microstructures and significant elemental segregation. Chemistries varied from calculated targets by up to 20 percent and macroscopic cracking occurred for chemistries greater than 60 percent Inconel 718. Flat wire welded deposits exhibited good mixing between the wire layers, however brittle cracking occurred adjacent to a 5 μm thick reaction layer. Ultrasonically‐consolidated samples demonstrated metallurgical bonding between pure Ni and commercially pure (CP) Ti foils, with material reaction limited to a 1 μm layer.

Originality/value

Producing nickel‐titanium graded composition materials had not been attempted by the selected manufacturing methods. A refined experimental program is needed to resolve the remaining technical issues.

Details

Rapid Prototyping Journal, vol. 11 no. 1
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 4 June 2019

Łukasz Brodzik and Andrzej Frąckowiak

This paper aims to present the problem of heating the damaged insulation of an orbiter.

Abstract

Purpose

This paper aims to present the problem of heating the damaged insulation of an orbiter.

Design/methodology/approach

Changes of the insulation’s thermal properties, made by adding conductive material of high value of specific heat in a form of a dope to the protective layer, were examined. An iterative algorithm determining a variable of dope concentration in the material was developed.

Findings

Determination of distribution of conductive material concentration was made for materials which, after verification, demonstrated the most beneficial effect on protective properties of the modified insulation layer. The problem of determining the distribution of metal filings concentration in the insulation layer of the coating belongs to inverse heat conduction problems.

Originality/value

Change of properties was to enable time extension of the LI900 insulation tile heating up to the maximal temperature and, additionally, to lowering this temperature.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 30 no. 6
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 14 July 2022

Chuanbao Nie, Bowen Fu and Qiang Gao

This paper aims to develop an efficient numerical method for nonlinear transient heat conduction problems with local radiation boundary conditions and nonlinear heat sources.

Abstract

Purpose

This paper aims to develop an efficient numerical method for nonlinear transient heat conduction problems with local radiation boundary conditions and nonlinear heat sources.

Design/methodology/approach

Based on the physical characteristic of the transient heat conduction and the distribution characteristic of the Green’s function, a quasi-superposition principle is presented for the transient heat conduction problems with local nonlinearities. Then, an efficient method is developed, which indicates that the solution of the original nonlinear problem can be derived by solving some nonlinear problems with small structures and a linear problem with the original structure. These problems are independent of each other and can be solved simultaneously by the parallel computing technique.

Findings

Within a small time step, the nonlinear thermal loads can only induce significant temperature responses of the regions near the positions of the nonlinear thermal loads, whereas the temperature responses of the remaining regions are very close to zero. According to the above physical characteristic, the original nonlinear problem can be transformed into some nonlinear problems with small structures and a linear problem with the original structure.

Originality/value

An efficient and accurate numerical method is presented for transient heat conduction problems with local nonlinearities, and some numerical examples demonstrate the high efficiency and accuracy of the proposed method.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 33 no. 1
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 21 March 2008

Manpreet Kaur, Harpreet Singh and Satya Prakash

This paper seeks to summarise the results of available research on the use of high velocity oxy‐fuel (HVOF) thermal‐spray technique to provide protection against high temperature…

1454

Abstract

Purpose

This paper seeks to summarise the results of available research on the use of high velocity oxy‐fuel (HVOF) thermal‐spray technique to provide protection against high temperature corrosion and erosion‐corrosion of materials.

Design/methodology/approach

This paper describes one of the recent thermal‐spray processes, namely HVOF thermal‐spray technology and presents a survey of the studies on the use of this technique to provide protection against corrosion and erosion‐corrosion of high temperature alloys, with a special emphasis on boiler steels.

Findings

High temperature corrosion and erosion‐corrosion are serious problems observed in steam‐powered electricity generation plants, gas turbines, internal combustion engines, fluidized bed combustors, industrial waste incinerators and recovery boilers in paper and pulp industries. These problems can be prevented by changing the material or altering the environment, or by separating the component surface from the environment. Corrosion prevention by the use of coatings for separating materials from the environment is gaining importance in surface engineering. Amongst various surface modifying techniques, thermal spraying has developed relatively rapidly due to the use of advanced coating formulations and improvements in coating application technology. One of the variants of thermal spraying, namely HVOF has gained popularity in recent times due to its flexibility for in‐situ applications and superior coating properties.

Research limitations/implications

This review covers mainly information that has been reported previously in the open literature, international journals and some well‐known textbooks.

Practical implications

The paper presents a concise summary of information for scientists and academics, planning to start their research work in the area of surface engineering.

Originality/value

This paper fulfils an identified information/resources need and offers practical help to an individual starting out on a career in the area of surface engineering for erosion‐corrosion and wear.

Details

Anti-Corrosion Methods and Materials, vol. 55 no. 2
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 1 December 1998

J. Bordzilowski and K. Darowicki

Industrial chimneys are a great part of environmental protection in industrial countries. In recent years many of them have been used to carrying away very aggressive gases from…

1892

Abstract

Industrial chimneys are a great part of environmental protection in industrial countries. In recent years many of them have been used to carrying away very aggressive gases from boilers and flue gas desulphurisation (FGD) units below acid dew‐point temperature. It is opf very important to modernize the old stacks and protect them against corrosion. The proper anti‐corrosion protection of modern high stacks is also an important technical and economical problem. In this paper the mechanism of acid dew‐point corrosion, as well as construction of industrial chimneys, methods of their anti‐corrosion protection and modernisation are described.

Details

Anti-Corrosion Methods and Materials, vol. 45 no. 6
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 1 August 1999

Jaroslav Mackerle

This paper gives a bibliographical review of the finite element methods (FEMs) applied to the analysis of ceramics and glass materials. The bibliography at the end of the paper…

2605

Abstract

This paper gives a bibliographical review of the finite element methods (FEMs) applied to the analysis of ceramics and glass materials. The bibliography at the end of the paper contains references to papers, conference proceedings and theses/dissertations on the subject that were published between 1977‐1998. The following topics are included: ceramics – material and mechanical properties in general, ceramic coatings and joining problems, ceramic composites, ferrites, piezoceramics, ceramic tools and machining, material processing simulations, fracture mechanics and damage, applications of ceramic/composites in engineering; glass – material and mechanical properties in general, glass fiber composites, material processing simulations, fracture mechanics and damage, and applications of glasses in engineering.

Details

Engineering Computations, vol. 16 no. 5
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 14 November 2008

George K. Stylios

Examines the fourteenth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects…

1248

Abstract

Examines the fourteenth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects. Subjects discussed include cotton fabric processing, asbestos substitutes, textile adjuncts to cardiovascular surgery, wet textile processes, hand evaluation, nanotechnology, thermoplastic composites, robotic ironing, protective clothing (agricultural and industrial), ecological aspects of fibre properties – to name but a few! There would appear to be no limit to the future potential for textile applications.

Details

International Journal of Clothing Science and Technology, vol. 20 no. 6
Type: Research Article
ISSN: 0955-6222

Keywords

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