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The effect of body incidence on the forces and moments on two afterbodies with a rearward facing jet in a subsonic uniform flow
No full textThis paper contains the results of an experimental investigation
into the effect of a jet issuing from two afterbodies (one a right
cylinder and the second conical) at incidence to a uniform subsonic
flow. The tests were performed at a Reynolds Number of 0.3 x 10^6
based on body diameter and maximum turnel velocity.
The presence of the jet issuing from an afterbody at incidence
significantly increases the magnitude of the normal force, axial force
and pitching moment arising from the external forces but not including
the direct reaction of the jet. On the bluff cylindrical afterbody
the effect of the jet is comparable in magnitude to the effect of
incidence. However the effect of the jet on the conical afterbody is
secondary to the effect of incidence
An analysis of an unstiffened cylindrical shell subjected to internal pressure and axial loading
No full textGeneral equations are obtained for the deflections and stresses
in long thin unreinforced cylinders, which are subjected to an axial
load and internal pressure. By making suitable simplifying assumptions,
results are presented which show the variation of the structural weight
parameter with the structural axial loading index, for both pressurised
and unpressurised shells. An allowance is made for the effects of
shell initial eccentricities on the buckling stress coefficient K, in
accordance with R. Ae.S. data sheet 04.01.01.
Extreme cases are considered, in which the shell is assumed to
be either fully effective (K = 0.6). 0:. completely ineffective (K = 0),
in resisting axial compressive loads. For this latter case, complete
pressure stabilisation of the shell is considered, and it is shown that
the weight penalty involved in using this design philosophy, is negligible
for a certain range of the structural loading index.
A simple modification to the analysis for this case, i.e. K = 0,
is made to allow for the effect of an external longitudinal bending moment
The flutter of thin, plane, elliptic panels
No full textThe effect of various parameters on the flutter of elliptic panels is studied by
simple theoretical analyses. For clamped edge panels, compressive membrane
stresses are shown to have destabilising effects. Structural damping is, in general,
destabilising, except for very low values of the ratio of structural and aerodynamic
damping coefficients.
The addition of a concentrated mass may also have a destabilising effect,
depending upon the position of the added mass. The effect of sweepback is stabilising
or destabilising, depending on whether the panel aspect ratio is less than, or
greater than, unity. The effect of variations in the edge conditions is shown for the
case of circular panels where the difference between simply supported and fully
clamped edges corresponds to a difference of 20% in critical panel thickness
Some aspects of the thermal degradation of epoxide resins. Part 1
No full textThis Note contains a review of previous work in the field of pyrolytic
degradation of epoxide resins, and a description of the development of an
instrument for this purpose, using the principle of gas chromatography.
The method depends on the pyrolysis of the material using an electrically
heated filament, the difficulties of this method are critically examined,
and attempts to overcome them described. The pyrolytic degradation in a
nitrogen atmosphere, of unhardened epoxide resin was investigated, likewise the
degradation of resin hardened with 1:2 diamino ethane and triethylenetetramine,
is described. An attempt has been made to explain, in terms of
possible degradation reactions, the actual compounds detected in the pyrolytic
break-down
The design and construction of a weld heat-affected zone simulator
No full textInvestigation of the structure and properties of the heat-affected zones
in welded joints is usually limited by their small size and their complexity.
One method of overcoming this problem is to simulate the structure at a
particular point in the heat-affected zone in a specimen of larger size by
imposing on it the thermal cycle sustained at that point.
The equipment described in this note uses a.c. resistance heating and
water cooling to impose thermal cycles on 2.5" x O.W' x O.W' specimens, the
thermal cycle being chosen by adjustment of a bank of variable resistors to
construct a voltage analogue. Control of specimen temperature is achieved
using a thyristor and two ignitrons to control the input at 44ov. to a
welding transformer. Feedback is applied from a thermocouple welded to the
specimen hot-zone. The equipment has been shown to produce the desired
thermal cycles in a reproducible manner
Studies of selected aspects of business in Europe
No full textPreface
The Cranfield Management Development Programme is an intensive ten
week course for middle management aged 28 - 45. The courses which are
held twice yearly started in 1964; the seventh of these, M.D.P.7, was
held from October - December 1967. The members of the course are drawn
from a variety of businesses and have previous experience in one or more
of the main fields of business activity, e.g. general management, marketing,
production, finance.
As part of the course two weeks are devoted to studying business
conditions on the continent of Europe. For this tour the members are
formed into small groups who study particular projects. Throughout the
visits the emphasis is on discussion with Senior Executives.
The specific objectives of the European Tour are:-
1. To use this exposure to a new environment to effect some measure
of re-evaluation of their past business experience in the United
Kingdom.
2. To acquaint members with business problems in different European
environments and to Provide an opportunity to discuss business
Problems with European managers.
To study problems that confront British companies who do business
in or with European countries.
M.D.P. 7 were in Europe from 12th - 24th November 1967 during which
Period the following cities were visited; Gothenburg, Copenhagen, Hamburg,
Rotterdam and Brussels. In each city discussions were arranged -with a
representative cross-section of the business community. These included
British Embassy Staff, British Chambers of Commerce, Local Bankers, Industrial
Companies, Advertising Agents, Trade Union Officials, Management Consultants,
British Subsidiaries and the E.E.C. Commission.
This report is split into sections representing the work of the project
groups.
The time available was not sufficient for a study in depth of any of
the chosen subjects. Nevertheless the large number of interviews and frank
discussions with British and foreign businessmen enabled the writers to gain
an insight into many aspects of European business. The report must
necessarily concern itself largely with opinions - those of the writers and
the persons interviewed.
The College would like to express its appreciation of the co-operation and
frank answers to searching questions received from all the businessmen, trade
unionists and others we had the pleasure of meeting during the tour. We would
like to give particular thanks to those who entertained the course members.
The success of the tour owes a very great deal to the hard work done on our
behalf by British officials. In particular thanks are due to the Foreign Office
(Economic Section), Board of Trade (Export Services Branch) and the Embassies
or Consulates in the cities visited
The improvement of micro-electronic component production operations by the application of cranfield developed precision engineering techniques
No full textFrom an examination of the Cranfield Universal Measuring Machine certain
features were selected. These features were linked together with some of the
manufacturing and assembly operations used to make dual-in-line integrated
circuits. The result was a group of design specifications for automatic
machines to effect substantial improvements in productivity in those manufacturing
operations.
The report describes the preliminary work which culminated in the
preparation of specifications, discussions with manufacturers and changes
which were made as a result of these discussions. The report concludes with
a number of proposals for continuing the main work and suggests certain
additional, separate, investigations which, it is thought, would produce
information of value to the semi-conductor industry
An analysis of the flight dynamics of a second generation SST aircraft
No full textThis interim report covers an initial overview of delta-wing aircraft static, dynamic and
control characteristics, collated from publications within the public domain and the
authors related research. This is to give the reader an overall understanding how a
delta-winged supersonic transport aircraft’ s characteristics differ to those of a
conventional civil transport aircraft.
This is followed by identifying the aircraft’s static and dynamic stability, with the effect
of speed and CG location on the aircraft dynamic modes specifically addressed.
Following this, a comprehensive investigation and analysis of the open loop response of a
SCT baseline aircraft, in both low-speed cruise and approach and landing conditions, has
been carried out. Both time and frequency domain techniques have been utilised. Finally,
conclusions are made based on the results of the work presented.Cranfield Universit
Fully discrete high-order TVD schemes for a scalar hyperbolic conservation law
No full textIn this paper we investigate fully discrete high-order TVD schemes for a scalar hyper-
bolic conservation law using flux limiters . Formulae which define Courant number
dependent TVD regions for second and third-order TVD schemes are established.
A semi-empirical TVD procedure for an m-th order scheme (m ≥ 4) are proposed
and tested.CI