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This paper reviews engineering work developed for blast analysis and design of industrial/residential and ammunition storage facilities. The review also covers work done for progressive collapse analysis and blast deflectors.

The first part of the paper describes characteristics of various types of explosions. Empirical and numerical models that were developed to estimate structural capacity are reviewed. The structural idealization, theoretical basis, and merits of various methods are also described. The influence of various parameters affecting the structural performance is discussed.

The material of the paper captures recent engineering developments that can be used by practitioners for blast analysis and design for industrial and residential buildings. Little emphasis was given in the published literature to develop simplified analytical models that can be used in practice to compute the dynamic response of buildings subject to accidental explosions. Furthermore, analytical expressions are required to compute the reduction in the stiffness due to impact loading.

Current building codes address conventional live, dead, wind and earthquake loads. Very few guidelines are available in practice for design of buildings subject to blast loading. The objective of this paper is to review and piece together recent engineering work developed for blast analysis and design of industrial/residential buildings and ammunition facilities. The paper provides useful resource material for the engineers in practice using recent techniques to design these structures. The review covers past three decades that can be used as a baseline for future developments.

The purpose of this paper is to predict and optimize the width of heat affected zone (HAZ) with better mechanical properties using suitable welding process and parameters for the fabrication of jet blast deflector (JBD) (high strength low alloy material of grade A588-B was used for fabrication) so that the JBD can sustain high exhaust parameters, because there are different welding zones formed due to the rapid cooling of weld metals. Out of the various zones of welding, HAZ remains the weakest zone in the entire weldment.

The present work describes the modeling, simulation, Modeling of three-dimensional plate and mess generation process are carried out using ICEM CFD software. FLUENT 16.0 software is used for ANSYS simulation where various models are used for analysis and results are validated with the experimental outcomes. High strength low alloy plates are welded by using shielded metal arc welding and tungsten inert gas (TIG) welding processes with two different electrodes. Optical microscopy and scanning electron microscopy were used for metallurgical study. The mechanical properties were evaluated by tensile strength test, vickers microhardness test and impact test. The corrosion resistance was evaluated by performing the potentiodynamic polarization test.

The present study indicated for better mechanical properties and improved corrosion resistance for TIG welded joints with type 308 L filler.

In aeronautical, defense, space and research organizations.

It can be shown from the scanning electron microscope technique that sound weld joint is produced with very good mechanical properties and joint also showed better corrosion resistance.

The purpose of this paper is to present a porous medium model for forced air convection in pin/plate‐fin heat sinks subjected to non‐uniform heating of a hot gas impinging jet. Parametric studies are performed to provide comparisons between inline square pin‐fin and plate‐fin heat sinks in terms of overall and local thermal performance for a fixed pressure drop.

Heat conduction in substrates is coupled with forced convection in the pin/plate‐fin flow channel. The forced convection is considered by employing the non‐Darcy model for fluid flow and the thermal non‐equilibrium model for heat transfer. A series of experiments is performed to validate the model for both the pin‐fin and plate‐fin heat sinks.

The present porous medium model is capable of capturing the presence of lateral heat spreading in the plate‐fins and the absence of lateral heat spreading in the pin‐fins under non‐uniform thermal boundary condition, attributing to the adoption of the orthotropic effective thermal conductivity for the solid phase in the energy equation. The present results show that the inline square pin‐fin heat sink has topological advantage over the plate‐fin heat sink, although the heat spreading through the plate‐fins on reducing the peak temperature on the substrate is pronounced.

This paper reports an original research on theoretical modeling of forced convection in pin/plate‐fin heat sinks subjected to the non‐uniform heating of an impinging jet.

A deflector for upwardly re‐directing the normally horizontal exhaust blast emitted from the exhaust nozzle of a reaction propulsive engine comprising: a supporting frame including a plurality of rigid laterally spaced side standards, each standard including an upright front member and an inclined rear member, said members being rigidly secured together near their upper ends; a plurality of elongated, spaced, superposed, horizontally disposed jet blast deflecting vanes bridging the respective spaces between said inclined rear members, all of said vanes having a concave upper surface and arranged with their forward edges at a lower elevation than their respective rear edges; and means rigidly securing the opposite ends of each vane between and to respectively adjacent inclined rear members.

In an aeroplane driven by engines providing a pair of adjacent, side‐by‐side rcarwardly directed jet blasts, a fairing on said aeroplane positioned between the paths of said blasts and having opposite surfaces closely adjacent the extent of the paths of said blasts, said fairing having a vertical portion thereof movably supported on a vertical pivot at the forward edge of said portion, means for moving said portion laterally into the path of one or the other of said blasts to create a lateral deflexion thereof, said vertical portion being divided vertically to define two panels, and means to separate said panels to move one of said panels into the path of one of said jet blasts and the other of said panels into the path of the other of said jet blasts, to deflect said blasts laterally and in opposite directions.

To review the most commonly used mechanical surface enhancement (MSE) techniques and their applications available in aerospace industry.

A brief description of each technique, as well as advantages and disadvantages over other techniques are given. The effects of those techniques on the surface characteristics and service properties of treated components are summarised. Finally, the applications of such techniques in the aerospace industry are presented with descriptive illustrations.

Provides a know‐how information and also comparison of techniques. Guides researchers and engineers to proper and appropriate use of each technique for relevant case or application.

The list of techniques can be extended to a wider range which may perhaps include specific and special purpose surface enhancement methods. The applications given in the paper are mainly industrial examples of such techniques which may reduce its usefulness in academia.

A very useful source of information and reference for companies and engineers working in repair and production technologies of aerospace components, and also a valuable guidance for researchers and academia or for those who are intending to make a research on surface enhancement technologies.

This paper introduces the most commonly used MSE techniques and their effects on the service properties of aerospace components, and provides a practical help and information for people in the industry and academia.

Under this heading are published regularly abstracts of all Reports and Memoranda of the Aeronautical Research Council, Technical Reports and Translations of the United States National Aeronautics and Space Administration and publications of other similar Research Bodies as issued.

RECOILLESS guns have been developed in Germany, Russia and America because of the lightness of the whole equipment, relative to the muzzle‐energy, that is possible in this class of gun. The German work began about 1937 and such guns (10·5 cm. L.G.40) were used in the invasion of Crete in 1941. The Russian 3‐inch recoilless gun was in use a little earlier. American interest in these guns dates from 1943, and a 7·5 cm. type has been announced. No British recoilless guns have been mentioned, but a theory of the internal ballistics of this form of gun has been published recently by the present writer.

Now established as the worldwide meeting place for all those engaged in the efficient and economic operation of international and national airports and military airbases, AIRPORT '81 will present the most comprehensive display of products and services to date.

TO say that the Twenty‐fourth S.B.A.C. Show was an unqualified success is perhaps to gild the lily. True there were disappointments— the delay which kept the TSR‐2 on the ground until well after the Show being one—but on the whole the British industry was well pleased with Farnborough week and if future sales could be related to the number of visitors then the order books would be full for many years to come. The total attendance at the Show was well over 400,000—this figure including just under 300,000 members of the public who paid to enter on the last three days of the Show. Those who argued in favour of allowing a two‐year interval between the 1962 Show and this one seem to be fully vindicated, for these attendance figures are an all‐time record. This augurs well for the future for it would appear that potential customers from overseas are still anxious to attend the Farnborough Show, while the public attendance figures indicate that Britain is still air‐minded to a very healthy degree. It is difficult to pick out any one feature or even one aircraft as being really outstanding at Farnborough, but certainly the range of rear‐engined civil jets (HS. 125, BAC One‐Eleven, Trident and VCIQ) served as a re‐minder that British aeronautical engineering prowess is without parallel, while the number of rotorcraft to be seen in the flying display empha‐sized the growing importance of the helicopter in both civil and military operations. As far as the value of Farnborough is concerned, it is certainly a most useful shop window for British aerospace products, and if few new orders are actually received at Farnborough, a very large number are announced— as our ’Orders and Contracts' column on page 332 bears witness. It is not possible to cover every exhibit displayed at the Farnborough Show but the following report describes a wide cross‐section beginning with the exhibits of the major airframe and engine companies.