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The purpose of this paper is to show a thermodynamic analysis to determine the contribution of each term of the total energy balance.

The thermodynamic analysis comprises a number of numerical simulations where some terms, typically ignored by the commonly used approximations, are removed from the total energy equation to quantify the effects in the flow and heat transfer fields. The case study is the differentially heated square cavity flow, in which the effects of work done by the pressure forces contribute significantly to the energy balance. Because local magnitudes are computed here for discussion, the dimensional form of the governing equations is preferred and a numerical model without any restrictive approximation about the role of the pressure is used.

The results show that the work of gravity forces term is in perfect balance with the work of pressure forces term, and thus, ignoring the contribution of one of them yields an incorrect solution. In addition, it is shown that the assumption of zero divergence of the Boussinesq approximation can be erroneous, even for a natural convection flow case where the temperature difference is very small.

As the flow and heat transfer governing equations are complex, simplifying assumptions are generally used; that is, the Boussinesq and low Mach number approximations. These assumptions are systematically adopted without any validation process and without considering that they modify the physical meaning of one or more of the thermodynamic quantities, particularly the pressure. This fact results in inconsistencies of the different forms of energy.

This is the first time that the terms of the total energy balance are quantified in such a way, in a differentially heated square cavity flow, which is a case study addressed by several authors.

This paper aims to present and then resolve the thermodynamic inconsistencies inherent in the usual Boussinesq model, especially with respect to the second law, and to highlight the effects of the correction.

The Boussinesq model (i.e. still assuming ▽v=0) is made thermodynamically consistent by maintaining in the heat equation, primarily the work of pressure forces, secondarily the heat generated by viscous friction. Numerically speaking, the modifications are very easy and hardly affect the computing time. However, new non‐dimensional parameters arise, especially the non‐dimensional adiabatic temperature gradient, ϕ.

There are presented and interpreted results of systematic numerical simulations done for a two‐dimensional square differentially‐heated cavity filled with air at 300K, with Rayleigh number ranging from 3,000 to 10⁸ and ϕ ranging from 10⁻³ to 2. All configurations are stationary and the fluid is far from its critical state. Nevertheless, the pressure‐work effect (similar to the piston effect) enhances the heat transfer while diminishing the convection intensity. The magnitude of this effect is non‐negligible as soon as ϕ reaches 0.02.

The domain where the thermodynamic Boussinesq model must be used encompasses configurations relevant to building engineering.

Exact second‐law analyses can be developed with the so‐corrected model.

Introduction Consider a hi‐fi loudspeaker manufacturing company acquired on the brink of insolvency by an American multinational. The new owners discover with growing concern that the product range is obsolete, that manufacturing facilities are totally inadequate and that there is a complete absence of any real management substance or structure. They decide on the need to relocate urgently so as to provide continuity of supply at the very high — a market about to shrink at a rate unprecedented in its history.

Instantaneous radial force induced from unsteady flow will intensify vibration noise of the centrifugal pump, especially under off-design working conditions, which will affect safety reliability of pump operation in severe cases. This paper aims to conduct unsteady numerical computation on one centrifugal pump; thus, unsteady fluid radial force upon the impeller and volute is obtained, so as to study the evolution law of instantaneous radial force, the internal relationship between radial force and pressure pulsation, the relationship among each composition of radial force that the impeller received and the influence of leakage rate of front and back chamber on radial force.

The unsteady numerical simulation with SST k-ω turbulence model was carried out for a low specific-speed centrifugal pump using computational fluid dynamics codes FLUENT. The performance tests and pressure tests were conducted by a closed loop system. The performance curves and the pressure distribution from numerical simulation agree with that of the experiment conducted. The unsteady pressure distributions and the instantaneous radial forces induced from unsteady flow were analyzed under different flow rates. Contribution degrees of three components of the radial force on the impeller and the relation between the radial force and leakage rate were analyzed.

Radial force on the volute and pressure pulsation on the volute wall have the same distribution tendency, but in contrast to the distribution trend of the radial force on the impeller. In the component of radial force that the impeller received, radial force on the blade accounts for the main position. With the decrease of flow rate, ratio of the radial force on front and back casings will be increased; under large flow rate, vortex and flow blockage at volute section will enhance the pressure and radial force fluctuation greatly, and the pulsation degree may be much more intense than that of a smaller flow rate.

This paper revealed the relation of the radial force and the pressure pulsation. Meanwhile, contribution degrees of three components of the radial force on the impeller under different working conditions as well as the relation between the radial force and leakage rate of front and rear chambers were analyzed.

In order to succeed in an action under the Equal Pay Act 1970, should the woman and the man be employed by the same employer on like work at the same time or would the woman still be covered by the Act if she were employed on like work in succession to the man? This is the question which had to be solved in Macarthys Ltd v. Smith. Unfortunately it was not. Their Lordships interpreted the relevant section in different ways and since Article 119 of the Treaty of Rome was also subject to different interpretations, the case has been referred to the European Court of Justice.

Aim of the present monograph is the economic analysis of the role of MNEs regarding globalisation and digital economy and in parallel there is a reference and examination of some legal aspects concerning MNEs, cyberspace and e‐commerce as the means of expression of the digital economy. The whole effort of the author is focused on the examination of various aspects of MNEs and their impact upon globalisation and vice versa and how and if we are moving towards a global digital economy.

The Equal Pay Act 1970 (which came into operation on 29 December 1975) provides for an “equality clause” to be written into all contracts of employment. S.1(2) (a) of the 1970 Act (which has been amended by the Sex Discrimination Act 1975) provides:

Knight's Industrial Law Reports goes into a new style and format as Managerial Law This issue of KILR is restyled Managerial Law and it now appears on a continuous updating basis rather than as a monthly routine affair.