Dynamic flow phenomena in a foam application unit

If, during the operation of a foam application unit, a change in the foam production is introduced, the change in the flow becomes noticeable at the point of application onlyafter a certain response delay time. During the operation of the unit it is necessary to take this response delay into consideration. By varying the flow of foam in the application unit, the mass content of foam in the unit is changed as a result of the changed pressure inside the unit. The response delay has been mathematically derived for the flow of agiven type of foam through pipes, as well as through a foam printing unit as a whole. A deviation in the yield of foam on the substrate can be avoided by considering the respons delay caused by a change in the foam production process

The flow properties of foam

The rheological behaviour of foam, prepared from an aqueous solution with lauryl sulphate as surfactant, has been measured with a viscometer as a function of the blow ratio, bubble diameter distribution and concentration of the thickener used. The influence of wall slip and of hysteresis effects on the rheological behaviour have been determined. Calculations and measurements pertaining to the pressure drop in pipes have been performed, in which the foam was considered as a compressible pseudoplastic whose rheology depended on blow ratio. The distribution of the foam passing through a closed distribution unit has been studied. This distribution unit consisted of a pipe and a cross-head distribution slit. Complementary measurements of the flow of foam through narrow slits have been made. The design of a closed foam distribution unit is discussed. The consequences of the choice of several design parameters are examined

Foam generation in a rotor—stator mixer = Schaumerzeugung in einem rotor—stator mischer

The foaming process of an aqueous liquid system with surface active agents and thickeners in a rotor-stator mixer has been studied.\ud \ud The foaming capacity of a rotor—stator mixer may be represented by a so-called mixing characteristic. The foamabilities of several liquid systems have been measured as a function of the mixer geometry and the rotational speed.\ud \ud The hydrodynamics in a rotor-stator mixer is characterized by a Newton—Reynolds relationship. The mechanism of foaming and the dependence of several mixing parameters are different for the turbulent and laminar flow regions. The mixing process is evaluated in both regimes. In the transition region from turbulent to laminar the foaming is very poor in comparison with that in the turbulent and laminar flow regimes.\u

Foam Generation in Rotor-Stator Mixers

One of the unit operations in foam technology is foam generation in a liquid/gas mixer. The foaming process of an aqueous liquid system with a surface-active agent in a rotor-stator mixer has been studied, and it was found that it could be represented by a mixing characteristic relating the liquid flow rate to the maximum gas flow rate needed to produce a foam without 'blow-by'. Too high a gas flow rate resulted in a short-circuiting flow of gas via the rotor shaft to the outlet. The influence of the number of rotor-stator blades, equipment size and operating pressure on the behaviour of the foam mixer has been investigated

De Herontdekking van de Kunst van het Maken: Lessen uit het Nederlands Biermaaklandschap

De ongekende technologische mogelijkheden van vandaag, zoals digitaliseringen zelflerende machines, kunnen ons leven sterk vergemakkelijken. Maar achter die moderne platformen en diensten gaan ook duistere zaken schuil, zoals de groeiende macht van tech-bedrijven. Dit stuk gebruikt echter de Nederlandse bierbrouwsector om een andere zijde te belichten van de belofte van de frictieloze samenleving: de waardering voor de ‘kunst van het maken’. Waar vervangen we de mensenhand door een mechanische, en waar zien we meerwaarde in een menselijke benadering van de maakkunst

New identities from remnants of the past: an examination of the history of beer brewing in Ontario and the recent emergence of craft breweries

We present an exploratory analysis of historical narratives and data covering 200 years of beer brewing in the Canadian province of Ontario. These data are used to illuminate the process of collective identity emergence in established organisational fields. We argue that established fields are typically littered with identity remnants from ancestral organisations and related institutional configurations that can facilitate the successful emergence of new collective identities. In our analysis we first show how multiple identity elements fell by the wayside as the beer brewing field matured and settled on a corporate path. We go on to detail how some of these identity elements were subsequently recovered during the recent decades which marked the successful emergence and proliferation of craft beer brewing. Our study has implications for research on collective identity and organisational legacy, and we stress the importance of taking a historical lens for understanding present day phenomena

De Herontdekking van de Kunst van het Maken: Lessen uit het Nederlands Biermaaklandschap

De ongekende technologische mogelijkheden van vandaag, zoals digitaliseringen zelflerende machines, kunnen ons leven sterk vergemakkelijken. Maar achter die moderne platformen en diensten gaan ook duistere zaken schuil, zoals de groeiende macht van tech-bedrijven. Dit stuk gebruikt echter de Nederlandse bierbrouwsector om een andere zijde te belichten van de belofte van de frictieloze samenleving: de waardering voor de ‘kunst van het maken’. Waar vervangen we de mensenhand door een mechanische, en waar zien we meerwaarde in een menselijke benadering van de maakkunst

The Renewal of Mature Industries: An Examination of the Revival of the Dutch Beer Brewing Industry

Many mature industries have recently experienced a remarkable revival. Yet, other important industries appear to remain impervious to change. While the evolution of industries is an important topic in the industrial organization and organizational sociology literature, theorists struggle to explain the determinants of industry renewal. In particular, there is a dearth in theories that explain (1) the formation of new organizational identities in mature industries, (2) the successful founding of new organizations and (3) the mobilization of entrepreneurs. In this dissertation, I build on the organizational sociology literature to forward an endogenous view on industry renewal arguing that the vulnerability of an industry toward renewal is determined by internal structural properties of the industry. Findings from three empirical studies of the recent revival of the Dutch beer brewing industry suggest that renewal is more likely in industries that (1) provide actors with a diverse reservoir of authentic identity elements for the formation of new organizational identities, (2) contain a significant number of ancestral organizations that left behind recyclable organizational elements, and (3) harbor a substantial number of actors that adhere to alternative ways of thinking compared to the industry’s “modus operandi”. Jointly, these findings demonstrate the potency of research under the eclectic umbrella of organizational sociology to provide explanations for the structural vulnerability of industries toward renewal. In particular, this dissertation calls for more research on the role of organizational destruction in industry evolution. Indeed, destruction appears to be an important generative process and an improved understanding of the role of destruction in industry renewal may be crucial for inspiring renewal in industries dominated by organizations that are too big too fail