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The purpose of this paper is to compute the pressure drop through sudden expansions and contractions for two‐phase flow of oil/water emulsions.

Two‐phase computational fluid dynamics (CFD) calculations, using Eulerian–Eulerian model, are employed to calculate the velocity profiles and pressure drops across sudden expansions and contractions. The pressure losses are determined by extrapolating the computed pressure profiles upstream and downstream of the expansion/contraction. The oil concentration is varied over a wide range of 0‐97.3 percent by volume. The flow field is assumed to be axisymmetric and solved in two dimensions. The two‐dimensional equations of mass, momentum, volume fraction and turbulent quantities along with the boundary conditions have been integrated over a control volume and the subsequent equations have been discretized over the control volume using a finite volume technique to yield algebraic equations which are solved in an iterative manner for each time step. The realizable per phase k‐ ε turbulent model is considered to update the fluid viscosity with iterations and capture the individual turbulence in both the phases.

The contraction and expansion loss coefficients are obtained from the pressure loss and velocity data for different concentrations of oil–water emulsions. The loss coefficients for the emulsions are found to be independent of the concentration and type of emulsions. The numerical results are validated against experimental data from the literature and are found to be in good agreement.

The present computation could not use the surface tension forces and the energy equation due to huge computing time requirement.

The present computation could compute realistically the two‐phase pressure drop through sudden expansions and contractions by using a two‐phase Eulerian model and hence this model can be effectively used for industrial applications where two‐phase flow comes into picture.

The original contribution of the paper is in the use of the state‐of‐the‐art Eulerian two‐phase flow model to predict the velocity profile and pressure drop through industrial piping systems.

The purpose of this paper is to provide an understanding of the effects of advertising based on economic cycles. To comprehend advertising effects in the restaurant industry from an economic cycle perspective, this study investigated both short- and long-run advertising effects under periods of economic contraction and expansion and compared those effects between the two economic periods.

The data were collected from the COMPUSTAT database for the restaurant industry (SIC 5,812) from 1979 to 2010. To estimate the economic cycles, the 2005 year-based real gross domestic product (GDP) was used from the Bureau of Economic Analysis. Also, all variables were depreciated by the value of the US dollar in 2005. For estimation, a single equation error correction model was used to examine the short-term and long-term effects of advertising.

The results of this study indicated that both the short- and long-term effects of advertising on sales growth were more obvious in contraction periods than in expansion periods. However, the short-run effects of advertising on brand equity did not significantly differ between expansion and contraction periods. Further, the long-term effects of advertising on brand equity were greater in expansion periods than in contraction periods. The findings suggest that restaurant firms should not reduce their advertising budgets during periods of economic contraction to take advantage of superior sales growth outcomes during these periods.

The results of this study provide restaurant managers with useful practical implications. During economic contraction periods, restaurant managers should not reduce advertising budgets to take an ascendant position in terms of sales growth. Though the net positive effect at year t + 1 of contraction periods was smaller than that of expansion periods for sales growth, this is temporal and the long-run positive effect on sales growth spreads into future periods. Thus, a counter-cyclical advertising strategy could compensate for reduced sales from weak customer demands during economic contraction periods.

There have been many empirical studies on the advertising effect in the literature. However, this study examined whether the effects of advertising differ between economic expansion and contraction periods. This specificity is helpful for industrial practitioners as well as academic researchers.

This study investigates whether cyclical turning points in the U.S. and U.K. stock markets are unevenly distributed over the year, that is, whether they are more likely to occur during certain months of the year. In examining this form of periodic seasonality, a Markov switching‐model is applied to U.S. and U.K. stock market chronologies of monthly peak and trough dates for the periods May 1835 through March 2000 and May 1836 through September 2000, respectively. In order to provide some evidence on robustness with respect to the sample data, results are obtained for the entire sample periods as well as for various sub‐. For both markets, the evidence indicates that while the probability of moving from an expansion to a contraction does not depend on the month of the year, the probability of switching from a contraction is greater for some months. Additionally, the durations of contractions, but not expansions, are dependent on the month of the year in which they begin.

This paper seeks to explore the fiber orientation distribution and rheological properties of turbulent fiber suspensions flowing through a contraction.

The Reynolds averaged Navier‐Stokes equation was solved with the Reynolds stress model to get the mean fluid velocity and the turbulent kinetic energy in the turbulent flow of a contraction with rectangular cross‐section. The turbulent velocity fluctuations were represented as a Fourier series with random coefficients. Then the slender‐body theory was used to predict the fiber orientation distribution, orientation tensor, additional shear stress and first normal stress difference of suspensions in the flow.

It is found that the longer fibers tend to align the streamline easily. Increased contraction ratio results in higher fiber alignment in the direction of flow. The fibers are weakly and strongly aligned in the direction of flow in the region near the inlet and the exit, respectively. Fibers are significantly more aligned in the plane of the contraction than in the x‐z plane. Contraction ratio and fiber length were shown to strongly and weakly affect the distributions of additional shear stress and first normal stress difference.

It is the first time that the fiber orientation distribution and rheological properties of turbulent fiber suspensions flowing through a contraction have been computed numerically. The computational approach and results are valuable to the design and operation of contraction used in the industrial processes.

The aim of this paper is to study the relationship between the popularity of discount stores and the aggregate business cycle: Does discounters' market share go up during economic contractions and go down during economic expansions? Does the aggregate business cycle contribute to the long-term growth of discounters' success? Does the relationship between discounters and the economy differ across discounter types, namely hard versus soft discounters?

The study will consider the relationship between discounters' market share and the aggregate economy between 1991 and 2008 for 15 Western European countries. Moreover, aggregated data is provided for the Western European region as a whole, which distinguishes hard from soft discounters' share. Recent time-series techniques are used to disentangle the temporary versus permanent effects of economic contractions on discounters' share.

The aggregate business cycle induces temporary upward and downward swings in discounters' market share. Moreover, part of the increase in discounters' share during an economic contraction remains beyond the contraction, resulting in a permanent boost in discounters' popularity. Same substantive findings are found for each discount type (i.e. hard and soft).

In economic contraction years the growth rate of both hard and soft discounters accelerates, leaving permanent scars on the performance levels of traditional retailers. Discounters should try to further enhance their increased popularity when the economy turns sour. Traditional retailers, on the other hand, should try to prevent consumers from switching to discounters during contractions. Future research should explore the strategies that are called for in order to do this.

Discounters are the fastest growing grocery format in Europe. Traditional retailers can no longer afford to ignore them. As such, a better understanding of the drivers of this growth is called for. This study highlights one of the potential drivers, namely the economic climate, a driver that is widely discussed in the business press with substantial implications for grocery channel management.

A method is given for the design of a two‐dimensional wind tunnel contraction for incompressible inviscid flow. The contraction is considered to join parallel channels of different width and is of finite length. The contraction boundary consists of two curved portions fairing smoothly into the channel walls at the upstream and downstream ends and a straight portion in between joining the other ends of Ihc curved portions. The shape of the boundary is determined by specifying: (i) constant velocities along the curved portions and (ii) the angle of inclination of the straight portion to the tunnel axis. The solution to the problem is obtained by working in the hodograph plane. For this purpose the contraction is considered to be made up of two distinct parts, upstream and downstream, and the solution is worked out for each separately. Results are given in tabular form for differing values of the above parameters (i) and (ii). It is hoped that the results will be found useful in the design of most low‐speed tunnels and particularly those with large contraction ratios. The results given here have been used in the design of a smoke tunnel (contraction ratio 15 to 1), a model of which has been built and tested with satisfactory results.

This study examines the durations of US stock market cycle expansions and contractions for the presence of seasonality. Specifically, it is determined whether the distributional characteristics (i.e., location and dispersion) of the durations of market expansions and contractions are dependent on the time of the year the market phase begins or ends. The duration data are obtained from a stock market chronology of monthly peak and trough dates for the period May 1835 through July 1998 and nonparametric rank‐based tests are used to test for the presence of seasonality. In order to provide some evidence on robustness with respect to the sample data, results are obtained for the entire sample period as well as for various sub‐periods. When the data are aggregated on a quarterly basis, the evidence suggests that seasonal structures are present in stock market cycle durations. These seasonals are related primarily to shifts in location over the course of the year and to when a market expansion or contraction begins. However, when the duration data are aggregated on a bi‐annual basis, support for seasonality is much more limited.

Micro, small and medium-sized enterprises are the live wire of construction industry in developing countries. These classes of establishments are most affected by economic contraction and turmoil, thus affecting their performance and survivability. Hence, the purpose of this study is to investigate and prioritize the survival determinants of construction consulting organization during economic contraction in Nigeria using quantity surveying firms as a focal point.

The study adopted the descriptive-survey design and quantitative data were collected through questionnaire purposely administered to quantity surveying firms in the Southwestern part of Nigeria. The data obtained from 99 quantity surveying firms on survival determinants were analysed using various statistical analysis such as mean score, standard deviation, Mann–Whitney U test, Kruskal–Wallis H test, and so on. Principal component analysis was used to identify the principal components of survival determinants, while the factors were prioritized using fuzzy synthetic evaluation (FSE).

The result of the analysis reveals eight factors that significantly determines the survival of firms during the period of economic contraction. Furthermore, the eight grouped factors were prioritized accordingly namely firm's innovation and diversification, ownership structure and networking, education level and management skills, and so on.

This study investigated the survival determinants of quantity surveying firms and prioritized it with the opinions of principal partners in quantity surveying establishments. As against obtaining large survey responses from all quantity surveyors in the study area that may not have practical experience of managing firms, the limited responses received provide valid basis to broaden the horizon of professionals and other stakeholders on the key determinants for firms to survive economic turmoil.

This study contributes to the body of knowledge by providing information on prioritized factors that must be considered in an appropriate order by quantity surveying firms to survive economic contraction.

This study examines the effect of business cycle, market return and momentum on the financial performance of socially responsible investing (SRI) mutual funds using data from two complete business cycles as defined by the National Bureau of Economic Research (NBER).

A “fund of funds” approach is used to identify the extent to which SRI financial performance is affected by the macroeconomic climate. The Fama-French Three-Factor model and the Carhart four-factor model are used to bring the results into alignment with commonly used finance methodologies.

The results indicate that SRI tends to preserve value during economic contraction more than it adds value during economic expansion. Market return is important during both expansion and contraction, while momentum is important only during expansion.

These findings suggest that double screening, for both financial and social performance, enables portfolio managers of SRI funds to have insight into those companies that are particularly vulnerable during times of economic contraction.

These results bring added clarity to the mixed findings found by previous researchers examining the relationship between corporate social performance (CSP) and financial performance.

This study reinforces the idea that the financial performance of companies with high ethical standards is comparable to the financial performance of the market as a whole during times of economic expansion and superior to the market as a whole during times of economic contraction.

Business cycle analysis, along with the Fama-French Three-Factor model and the Carhart four-factor model, brings SRI research more into the realm of conventional financial analysis than previous studies.

A finite volume method is applied to numerical simulations of steady isothermal and non‐isothermal flows of fluids obeying different constitutive equations: Newtonian, purely viscous with shear‐thinning properties (Carreau law) and viscoelastic Upper Convected Maxwell differential model whose temperature dependence is described by a William‐Landel‐Ferry equation. The flow situations concern various abrupt axisymmetric contractions from 2:1 to 16:1. Such flow geometries are involved in polymer processing operations. The governing equations are discretized on a staggered grid with an upwind scheme for the convective‐type terms and are solved by a decoupled algorithm, stabilized by a pseudo‐transient stress term and an elastic viscous stress splitting technique. The numerical results highlight the influence of temperature on the flow situations, and also the complex behaviour of the materials under non‐isothermal conditions.