Design Of Fluid Systems Research Articles

Capacitance-based mass flow rate measurement of two-phase hydrogen in a 0.5 in. tube

Mass flow rate is a critical measurement parameter when designing cryogenic hydrogen fluid systems. It is important in custody transfer applications for calculating financial obligations, fundamental fluid property research/modeling, and fluid system design applications to optimize chill down performance, maintain thermal equilibriums, and provide feedback control for pumps and valves. However, due to the large temperature differential between cryogenic fluids and the environment, there is often multiphase flow during system chilldown and steady state operation. Current available cryogenic flow measurement techniques are not equipped to deal with the complex multiphase flow inherent in cryogenic fluid systems, resulting in significant measurement errors. This mass flow measurement inaccuracy can cause financial loss, system instability, and even component failure, resulting in a strong market demand for a multiphase cryogenic mass flow meter to optimize and control sophisticated and costly cryogenic systems. This paper presents a solution in the form of a novel capacitance-based technique for measuring the multiphase mass flow rate of cryogenic hydrogen in a terrestrial environment. The device was calibrated and tested on a ½” tube multiphase hydrogen flow loop at a cryogenic hydrogen test facility. An error of ± 2 % full scale was achieved across a range of flow conditions, including transient and steady states.

An Experimental Evaluation of the APR1000 Core Flow Distribution Using a 1/5 Scale Model

The experimental data of core flow distribution are indispensable for obtaining licensing and facilitating the design of fluid systems of nuclear reactors. In this study, an Advanced power reactor Core flow and Pressure (ACOP) test facility was established to experimentally simulate the internal flow of the Advanced Power Reactor 1000 (APR1000) on a reduced length scale of 1/5. The core region was simulated by using 177 core simulators representing the fuel assemblies of the APR1000. The APR1000 flow distributions were synthetically identified by accurately measured parameters: the core inlet flow rate and outlet pressure under the four-pump balanced and unbalanced flow conditions. The overall inlet flow rates ranged from 87.7% to 112.0% relative to the averaged flow rate. Here, we scrutinize the flow distributions considering the flow conditions and internal structures and briefly describe the applied scaling method and design concept of the test facility.

A novel engineering tool for creative design of fluid systems

Computational fluid dynamics is not often used early in the conceptual design stage of product development due to the lengthy computation times involved with solving complex computational fluid dyn...

Enhanced Aqueous Fracturing Fluid Recovery from Tight Gas Formations: Foamed CO2 Pre-pad Fracturing Fluid and More Effective Surfactant Systems

Abstract Under pressured, tight, deep formations represent a challenge in terms of recovery of fracturing fluids. CO2, N2 and binary high quality foams are widely used in this type of reservoir due to their capacity to energize the fluid and improve total flowback volume and rate. Surfactants designed to reduce surface and interfacial tension are also a key element in the design of fluid systems to enhance recovery and reduce entrapment of fluid barriers within the formation. Enhanced fluid recovery improves overall completions economics due to less total treatment cost and less time required for flowing back fluids. The most important benefit is achieving a less damaged proppant pack, resulting in higher fracture conductivity. This document will discuss the application of CO2 foamed fluids and surfactants to enhance fracturing fluid recovery and other techniques adopted by one operator in the Wild River Field to improve completion practices. Introduction Unconventional gas-in-place in Canada (not including gas hydrates) has been estimated at approximately 2,589 Tcf; 1,500 Tcf of these reserves correspond to tight gas(1). Achieving optimum development of these reserves is challenging due to the low permeability (< 0.1 mD) and abnormal pressures that characterize tight gas sands. The challenges are both technical and economic. Unconventional reservoirs, in general, require higher capital expenditure compared to conventional reservoirs(2). Commercial rates are, in most cases, achieved by hydraulically fracturing pay zones. The perfect fracturing job in these cases would consist of an inexpensive, long fracture with infinite conductivity, 100% propped, 100% effective length, and contained in the pay zone with 100% fluid recovery. However, realistically we know that a tight gas-bearing zone faces abnormal pressure, low permeability, clay swelling and migration, capillarity effects, near-wellbore restrictions and formation complexity and heterogeneities. These characteristics usually result in damage from drilling and cementing operations, water phase trapping, screenouts, proppant not carried to the far field, dehydrated polymer, etc. This paper will review different practices that are proving to mitigate some of these problems, focusing on enhanced fracturing fluid recovery with the aid of high-quality CO2 foamed fluid as a pre-pad and the addition of solvents/surfactants. The experience gained after performing 192 fracturing jobs in the Cadomin Formation, Wild River Field in central Alberta will help illustrate the benefits of the practices recommended in this document. Description: Cadomin Formation, Wild River Field The practices described in this document are based on the experience acquired fracturing in the Cadomin Formation of the Wild River Field in Alberta, Canada (Figure 1). The Cadomin Formation is a deep basin, tight gas formation with NW-SE trending, usually the lowest reservoir in sequence, and consequently, highly stressed. The Cadomin Formation is a braided channel deposit, sourced by conglomeratic and sandstone alluvial fans to the west. This zone is present in every Wild River well(3). The common reservoir parameters of the Cadomin Formation are presented in Table 1. FIGURE 1: Wild River Field location(3). Table 1: Reservoir properties.

Simple Approach to the Cleanup of Horizontal Wells With Prepacked Screen Completions

Openhole completions with prepacked screens are increasingly the completion of choice for horizontal wells requiring sand control. For maximum productivity from these wells, preventing mud damage to the formation and the screen or removing it before bringing the well onto production is vital. A common industry approach to this problem is to displace the drilling mud to an aqueous clear fluid before production, typically followed by a breaker fluid. This paper details an alternative approach: bringing the well on without cleanup. The paper outlines the decision-making process, shows how the drill-in-fluid ad cleanup operations are designed, explains how laboratory resting can be used to support the design philosophy, and highlights that quality control of the mud system while drilling is critical to the success of such a well. Case histories in two very different reservoirs are presented that illustrate the success of this approach.

Development of an Expert System To Assist With Complex Fluid Design

Summary The design of fluid systems for well completion has always been a perplexing problem for engineers and chemists. Material incompatibilities, chemical interaction, physical restrictions, and cost considerations build a great deal of complexity into the designs. Many engineers do not have the theoretical background needed to evaluate the numerous available additives. Others may not have the practical experience required to optimize a fluid treatment. Expert systems, with their unique structure and knowledge representation, can be used efficiently as tools to advise engineers of the proper base fluids and additives to be selected for a given set of well conditions. Valuable resources and operation costs can be saved by providing good material recommendations. In addition, use of expert systems can help centralize and retain expertise within the organization. The fundamental elements of expert systems—namely, the knowledge base, inference engine, and user interface—are addressed in this paper, along with knowledge acquisition and system implementation. Acid Expert, an expert system designed for matrix-acidizing-treatment recommendation that has been released to locations worldwide, is used as an example for much of the discussion.

Some problems on fluid transient phenomena.

For the analysis and design of fluid systems, especially whose systems in which fluid transients in a pipe play an important role, numerical calculation by the method of characteristics is a very useful tool. Because the method of characteristics is suitable for computer programing, even fluid transients in complicated pipelines can be analyzed with less effort. Using this method, the surge pressure and transient flow rate in a pipeline can be accurately analyzed. Due to the reliance on computer simulations, it becomes more and more important and necessary to fully comprehend physical phenomena through experiments and to make use of the results of the design and control of fluid systems.