# circulation time
## English
### Noun

circulation time (countable and uncountable, plural circulation times)
* (engineering, drilling) The amount of time required for mud to circulate from the suction pit, enter into the wellbore and then return to the surface.
** 2015, Izzy M. Kutasov, Lev V. Eppelbaum, Pressure and Temperature Well Testing, page 14:To use this solution for any value of circulation time, we introduce below the adjusted circulation time.
** 2018, Werner Kass, Tracing Technique in Geohydrology, page 513:The engineer requires knowledge of the circulation time if the drilling mud is to be changed.
** 2020, Mehrdad Massoudi, Mathematical Modeling of Fluid Flow and Heat Transfer in .Petroleum Industries and Geothermal Applications, page 312:Since the deeper annulus temperature is lower than that of the corresponding deeper formation, the longer the circulation time of drilling fluid is, the more heat in the deeper formation is taken away by the drilling fluid.
* (medicine) The time it takes for a fluid to complete its circuit of the body, especially the time it takes blood to circulate.
** 1949, Cecil James Watson, Outlines of Internal Medicine - Volumes 1-5, page 256:Table II shows the results of measurements of the diastolic volume of the heart, the stroke output of the heart, the mechanical work of the heart, the circulation time and calculated increase in mechanical efficiency of the heart as well as the venous pressure in the systemic circulation in cases of heart failure.
** 1953, Leena Tuuteri, On the Circulation Time and the Oxygen Saturation of Sinus Blood in Severe Infantile Gastroenteritis, page 24:No correlation has been found between blood pressure and circulation time in either healthy or diseased individuals (Blumgart & Weiss 1927, Olsone 1941, Kerpel-Fronius 1950).
** 2013, István Rusznyák, Mihály Földi, György Szabó, Lymphatics and Lymph Circulation, page 271:The time measured by us can, thus, be regarded as the true "lymph circulation time".
** 2013, Alfred P. Fishman, Dickinson W. Richards, Circulation of the Blood: Men and Ideas, page 105:In 1897 George Neil Stewart, formerly a student of the English physiologist William Stirling, and later professor of physiology at Western Reserve University, published a series of experiments on the circulation time.
* (economics, archaeology) The time in which capital is bound up the form of a commodity; the time in which a manufactured item is in use.
** 1984, John L. Bintliff, European Social Evolution: Archaeological Perspectives, page 28:tracing the precise circulation routes and circulation time of exchange goods may offer finer detail on social questions, cf. Frankenstein and Rowlands ( 1978 ).
** 1984, Matthew Spriggs, Marxist Perspectives in Archaeology, page 92:This would seem to confirm our hypothesis that increasing circulation time reflects periods of declining supplies of bronze.
** 2005, Kristian Kristiansen, Michael Rowlands, Social Transformations in Archaeology, page 93:Swords were classified according to degree of wear—that is, circulation time.
** 2006, Karl Marx, Capital:During its circulation time, capital does not function as productive capital, and therefore produces neither commodities nor surplus-value.
** 2016, Simon Choat, Marx's 'Grundrisse':We can think of the capitalist's desire to reduce circulation time in terms of turnover time.
** 2018, Teinosuke Otani, A Guide to Marxian Political Economy, page 295:Industrial capital requires —to a greater or lesser degree—time (circulation time) and costs (circulation costs) for the sale.
* (oceanography, geosciences) The time it takes oceanwater, moving via currents, to move between two points, or to complete a cycle back to its starting point.
** 1996, Natural Climate Variability on Decade-to-Century Time Scales, page 359:Ê is scaled by the circulation time and a factor to remove the salinity dimension.
** 2007, Hendrik M. van Aken, The Oceanic Thermohaline Circulation: An Introduction, page 96:The aging from the Southern Ocean to the North Pacific, expressed in a δ$^{14}$C decrease of 90 to 100%, requires a circulation time from the Southern Ocean to the North Pacific of the order of 950 years.
** 2013, Joseph Pedlosky, Ocean Circulation Theory, page 5:Assuming that the large-scale flow pattern is essentially stationary over the circulation time, L/U, of the interior flow, the ratio of the relative acceleration to the Coriolis acceleration in (1.2.1(, i.e., the ratio of the first to the second term in the momentum equation is:
* The amount of time that a fluid takes to complete a cycle around a vessel in which it is being mixed or stirred.
** 1991, Klaas van't Riet, Johannes Tramper, Basic Bioreactor Design, page 403:This is the same order of magnitude as circulation time and mixing time for large fermenters.
** 2003, Edward L. Paul, Victor A. Atiemo-Obeng, Suzanne M. Kresta, Handbook of Industrial Mixing: Science and Practice, page 729:As stated previously, both time to equilibrium and the competition between coalescence and dispersion depend on circulation time.
** 2008, Lyle Albright, Albright's Chemical Engineering Handbook, page 626:Every vessel has a distribution of circulation times.
* (computing, computer science) The amount of time that elapses in a multiprocess system from the time when a process is loaded for execution until the time when the same process is next loaded for more processing.
** 1982, Cees J. van Spronsen, Lutz Richter, Microsystems: Architecture, Integration, and Use, page 24:The circulation time of a slot in front of an access window has been chosen as the basic unit of time.
** 2001, Per Brinch Hansen, Classic Operating Systems, page 94:The first record for the day gives a base time, while subsequent records for the day each have a circulation time associated with them; the circulation time is thus calculated by subtracting from the current log-on time the log-on time of the previous run by the same user.
** 2006, Nabil Hasasneh, Ian Bell, Chris Jesshope, “Scalable and Paritionable Asynchronous Arbiter for Micro-threaded Chip Multiprocessors”, in Werner Grass, Bernhard Sick, Klaus Waldschmidt, editor, Architecture of Computing Systems - ARCS 2006, page 266:This mechanism provides latency hiding by decoupling the micro-threaded processor from the token circulation time.

#### Derived terms

* blood circulation time