New Goff–Gratch, Hyland–Wexler, and you can Wagner–Pruss formulas was monotonous and you will inconvenient for usage for the calculating the saturation steam pressure

New Goff–Gratch, Hyland–Wexler, and you can Wagner–Pruss formulas was monotonous and you will inconvenient for usage for the calculating the saturation steam pressure

Koutsoyiannis recently derived a formula getting calculating saturation vapor pressure out-of liquids according to the Clausius–Clapeyron picture and you will indicated that the fresh relative difference in the resource datasets try quick off ?40° in order to 50°C (Koutsoyiannis 2012)

There’ve been far research to your creating the fresh saturation vapor stress. Bosen offered an algorithm to have calculating new saturation steam tension out-of water that have practical precision on the temperature cover anything from ?51.1° to 54.4°C (Bosen 1960). Langlois created a beneficial fractional algorithm to own calculating the newest saturation steam pressure out of h2o and you may compared the results to your noticed philosophy within the Byers (1959) and the algorithm inside the Berry mais aussi al. (1945). This new payment mistake against the brand new observations try found to be shorter than simply 0.5% over the heat directory of 0°–35°C (Langlois 1967). Richards derived a several-studies polynomial for the saturation steam tension from liquids inside temperatures consist of ?50° to help you 140°C (Richards 1971). Tabata suggested good quadratic formula you to produced the fresh new saturation steam pressure that have an indicate payment error of 0.17% in temperature start around 0° so you’re able to 35°C (Tabata 1973). Lowe given a 6th-training polynomial formula getting calculating the brand new saturation steam tension out-of h2o away from ?50° to fifty°C and you will examined it contrary to the Goff’s formula. The outcomes indicated that the precision try extremely high (Lowe 1977). Rasmussen presented good four-studies polynomial and you may a sixth-studies polynomial for figuring new saturation vapor stress more than liquid (regarding ?50° to 50°C) and over freeze (from ?50° to 0°C) and another four-studies polynomial into saturation steam tension more freeze. The most cousin mistake is actually low (Rasmussen 1978). Gueymard used a least squares supply of about three formulas having brand new saturation steam stress more than drinking water and compared the computed efficiency with the the new ASHRAE resource study. It had been shown that these three algorithms you are going to calculate the brand new saturation vapor pressure with great accuracy (Gueymard 1993). Sanjari proposed a nonlinear formula to possess calculating the latest saturation vapor tension away from 75 natural compounds that with numerous regression study, and you will review of your computed performance plus the data about literary works showed that brand new mean cousin deviation involved 0.1% to have liquid (Sanjari 2013). The temperature range was not considering inside Sanjari (2013).

Money put a good minimax fitted techniques along the temperature a number of very interest in meteorology and you will derived a couple equations having figuring the saturation vapor stress off h2o (out of ?20° in order to fifty°C) as well as freeze (out of ?50° so you can 0°C), respectively (Money 1981)

The aforementioned-said formulas continue to be state-of-the-art. Certain researchers made certain tries to establish effortless equations designed for brand new resource analysis in the shape of regression study. Tetens advised one or two short formulas, certainly one of which had been of one’s Magnus means, to own measuring the newest saturation vapor stress of liquids as well as frost (Tetens 1930). New vapor tension philosophy offered by so it formula was acceptable for most meteorological objectives (Murray 1967), however the relative error provided by the latest Tetens formula increased with ). In particular, on heat below ?25°C the new mistakes was above step 1% (Murray 1967). Bolton brought an empirical algorithm toward saturation vapor pressure away from liquids and indexed your error are 0.4% across the temperature are normally taken for ?35° to help you 35°C (Bolton 1980). Alduchov and Eskridge generated a great access to an iterative processes and you will the very least squares method of improve the latest coefficients of Magnus algorithm and you will recommended a few equations for figuring this new saturation vapor tension more liquids (out of ?40° in order to fifty°C) as well as freeze (away from ?80° to help you 0°C), correspondingly. These two equations produced maximum cousin mistake regarding lower than 0.384% and you will 0.213%, respectively (Alduchov and you may Eskridge 1996). Leckner calculated the fresh saturation vapor stress out-of liquid having fun with an easy exponential mode (Leckner 1978). Stephens projected the fresh saturation vapor stress out of liquids that with an excellent effortless algorithm that has been in line with the Clausius–Clapeyron picture (Stephens 1990).

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