FLUID BULK MODULUS: COMPARISON OF LOW PRESSURE MODELS
Keywords:
fluid bulk modulus models, hydraulic fluid, air/gas dissolving, adiabatic, isothermal, volumetric fraction of air/gas, critical pressureAbstract
Fluid bulk modulus is a fluid property that has been studied extensively over the past. The numerical value of this property depends on the operating conditions, the amount of entrained air/gas, and the way compression is applied and to some extent, the mathematical form it is defined. In a companion paper, an extensive review of fluid bulk modulus was presented. From this review, it was established that many models for fluid bulk modulus in the low pressure range (below critical pressure) have been forwarded. However, many of these models are based on assumptions that have not been explicitly defined. This paper considers these models and attempts to quantify the underlying assumptions. In addition some modification to these models are proposed in order to compare their prediction in the case where air/gas in entrained, for example. The paper concludes by categorizing the models into two groups and recommending the best model that can be used for each group. Finally some problems which observed in the models are discussed and future work for solving these problems presented.
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