ABSTRACT The research and development of the Dosin® and the medical injection system in which it is used was initiated in response to a demand for a new and improved method of delivering fluids to patients. The key requirement was to make the use of refillable syringes obsolete in a cost- effective and user-friendly alternative. Most syringes, despite their accurate delivery quotas, have a limited volume that necessitates frequent monitoring and filling or changing. This very act is time consuming and potentially dangerous in inexperienced hands. The new principle of the device makes it capable of delivering (medical) fluids of various consistencies in extremely precise amounts regardless of the fluid viscosity. The outlet of the Dosin® goes through another innovation, the bubble detector, which detects any change in direction of a light beam that passes through the content of the outlet. Thus, should an air bubble enter the outflow and hence be about to enter the blood stream of a patient, the flow of fluid will halt immediately and an alarm will notify the user of the problem.The cyclic flow is useful in interventional radiology since it prevents clotting and increases the mixing with the blood. The flow rate varies from 0.03 mL/s to 5 mL/s and it is recommended to use fluid with a viscosity lower than 3 mPa.s. The outlet pressure is recommended below 300 mm Hg. The Dosin® must be replaced after each patient, alternatively after maximum 24h continuous use.
In an earlier paper (1) a new pump device for medical applications was described. This enabled a continuous flow of saline, barium contrast agent and gases. We now report further study of this device: The use of gases was experimentally studied to give a basis for use in CT-colonography. We also report experiences from injection of barium contrast agent via a naso-duodenal tube for radiological investigation of the small intestine in patients with gastrointestinal suffering. The radiation exposure to the x-ray staff was reduced. The investigation procedure was standardised and shortened.
En lärobok (främst riktad till yrkeshögskolan) om hur man undviker mätfel, om olika mätprinciper och om hur mätutrustning av olika slag bäst används och monteras. Främst handlar det om temperatur, tryck, flöde och nivå men även annat som finns i en processindustri.
Prestudy of test bed for fuel cells This report investigates the potential needs and benefits of a Swedish national test bed for fuel cell and hydrogen technologies. The analysis is based on an interview study among 43 organisations within the field, as well as on inventory studies on existing test infrastructure in Sweden. The result is aggregated into a proposal that describes a test bed in terms of functionality and organisation.
In the framework of the ongoing EMRP Joint Research Project (JRP) ENG 60 “Metrology for LNG” (2014-2017), co-funded by the European Union, a number of metrological challenges associated with custody transfer and transport of LNG will be faced. The project consists of four technical work packages (WP), whereby the main objective is to reduce the measurement uncertainty of LNG custody transfer by a factor two. The focus in WP1 is the design and development of a traceable mid-scale calibration standard for LNG mass and volume flow. The goal is to provide traceable mass and volume flow calibrations up to 400 m3/h (180000 kg/h). In WP2, the emphasis is on the development and validation of a LNG sampling and composition measurement reference standard, consisting of sampler, vaporizer, gas standards, and gas chromatography (GC), which will be used to test and calibrate commercially available LNG sampling and composition measurement systems. The priority in WP3 is given to the development and validation of a method for the determination of the methane number, including correlations based on the LNG composition and corrections for traces of nitrogen and higher hydrocarbons. Since physical properties and quantities play an important role in LNG custody transfer, WP4 comprises reference quality density measurements of LNG to validate and improve models for LNG density predictions, the uncertainty evaluation of enthalpy and calorific value calculations and the development of a novel cryogenic sensor for the simultaneous measurement of speed-of-sound and density. The present paper gives an overview of recently achieved objectives within the project and provides an outlook to future activities.
Within the framework of a research project regarding investigations on a high-pressure Coriolis mass flow meter (CMF) a portable flow test rig for traceable calibration measurements of the flow rate (mass - and volume flow) in a range of 5gmin-1 to 500gmin-1 and in a pressure range of 0.1MPa to 85MPa was developed. The measurement principle of the flow test rig is based on the gravimetrical measuring procedure with flying-start-and-stop operating mode. Particular attention has been paid to the challenges of temperature stability during the measurements since the temperature has a direct influence on the viscosity and flow rate of the test medium. For that reason the pipes on the high-pressure side are double-walled and insulated and the device under test (DUT) has an enclosure with a separate temperature control. From the analysis of the first measurement with tap water at a temperature of 20°C and a pressure of 82.7MPa an extensive uncertainty analysis has been carried out. It was found that the diverter (mainly due to its asymmetric behaviour) is the largest influence factor on the total uncertainty budget. After a number of improvements, especially concerning the diverter, the flow test rig has currently an expanded measurement uncertainty of around 1.0% in the lower flow rate range (25gmin-1) and 0.25% in the higher flow rate range (400gmin-1) for the measurement of mass flow. Additional calibration measurements with the new, redesigned flow test rig and highly viscous base oils also indicated a good agreement with the theoretical behaviour of the flow meter according to the manufacturers' specifications with water as test medium. Further improvements are envisaged in the future in order to focus also on other areas of interest.
One of the most important process parameters in power plants is the flow rate that is measured in the secondary or feedwater circuit. To improve our understanding of the behaviour of flow instruments for this use, a work package within the European research project JRP "Metrology for improved power plant efficiency" concerning "Flow" was initiated. It comes under the direction of SP, Technical Research Institute of Sweden. Many power plants have to operate below their licensed rating because of the measurement uncertainty of the flow in the feedwater circuit. For that reason - in the field of traceable flow measurement - four European NMIs (PTB, SP, DTI, BEV) investigated four flow sensors based on different measuring principles. The aim is to find a method to extrapolate low temperature calibrations to high temperatures in order to measure feedwater flow with an uncertainty in the range of 0.3%-0.5%. This paper describes the work undertaken at SP on investigations of an orifice plate.
A Pt100 sensor is under normal conditions a very accurate and stable sensor for temperature measurements. Two important factors that can have influence on the results are its drift during time and the hysteresis effect at temperature changes. Different types of Pt100 sensors will show varying sensitivity for these effects. This study includes a number of partially supported wire type Pt100 sensors mainly used as reference sensors at different industries and laboratories. For most of the sensors, there is a history of calibration data for several years. By using a dry block calibrator, the hysteresis effects of the sensors are measured in the temperature range 0 °C up to 500 °C, depending on the calibration range of the sensor. The suitability of the method is evaluated by measurements of the stability of the dry-block and the repeatability of hysteresis tests. The evaluation shows that it is possible to measure hysteresis effects above a few mK. The tested Pt100 sensors exhibits hysteresis effects of 20 mK peak-to-peak as most, which is in the same magnitude as the uncertainty of the calibration and also more significant than the annual drift. The best sensors showed a hysteresis of just a few mK.
Radiation thermometers are traditionally mostly used in high-temperature applications. They are, however, becoming more common in different applications at room temperature or below, in applications such as monitoring frozen food and evaluating heat leakage in buildings. To measure temperature accurately with a pyrometer, calibration is essential. A problem with traditional, commercially available, blackbody sources is that ice is often formed on the surface when measuring temperatures below \(0\,{}^{\circ }\hbox {C}\). This is due to the humidity of the surrounding air and, as ice does not have the same emissivity as the blackbody source, it biases the measurements. An alternative to a traditional blackbody source has been tested by SP Technical Research Institute of Sweden. The objective is to find a cost-efficient method of calibrating pyrometers by comparison at the level of accuracy required for the intended use. A disc-shaped blackbody with a surface pyramid pattern is placed in a climatic chamber with an opening for field of view of the pyrometer. The temperature of the climatic chamber is measured with two platinum resistance thermometers in the air in the vicinity of the disc. As a rule, frost will form only if the deposition surface is colder than the surrounding air, and, as this is not the case when the air of the climatic chamber is cooled, there should be no frost or ice formed on the blackbody surface. To test the disc-shaped blackbody source, a blackbody cavity immersed in a conventional stirred liquid bath was used as a reference blackbody source. Two different pyrometers were calibrated by comparison using the two different blackbody sources, and the results were compared. The results of the measurements show that the disc works as intended and is suitable as a blackbody radiation source.
The cobalt–carbon (Co–C) eutectic point at 1324∘C has in previous studies proved to be suitable as a reference for thermocouple calibration above 1100∘C. For types S, R, and B, it fills the gap between the copper point and the palladium point, and for Pt/Pd thermocouples, it extends the range from the copper point. This work describes the implementation of the Co–C reference point at the Technical Institute of Sweden (SP). A Co–C cell was developed and manufactured at SP in a collaboration project with the National Metrology Institute of Japan (NMIJ). The principle of the cell is a hybrid design with double walls, both for the outer crucible and the inner thermometer well, with graphite foil between the walls. To evaluate the performance of the developed cell (SP cell), a comparison between the SP cell and another cell, manufactured and provided from the National Physics Laboratory (NPL) in England, is performed using Pt/Pd thermocouples as transfer standards. The comparison showed very good agreement, with differences below 40 mK, using the same furnace and two different thermocouples. The expanded uncertainty (k=2) for the comparison was estimated to be 70 mK.
Controlling thermal power in the feed water line of a power plant presupposes both accurate flow and temperature measurement. In this application the temperature measurement is usually a single Pt-100. This results in a measurement error of several kelvin. In this study we have investigated two different sensors based on the speed of sound (SoS) in the flowing medium for measuring the average temperature across a flow pipe cross-section. This is a task within the on-going European research project called ENG-06. The two SoS-based temperature measuring sensors were investigated under laboratory conditions. Investigations were done using both homogenous and non-homogenous temperature distributions with temperature differences up to 25 K. In addition the influence of pressure (50-200 kPa) and flow rates (0.5-2 m/s) on the SoS devices were also investigated. Our results show that the SoS-based temperature principle is working. Furthermore, depending on the measurement conditions a SoS temperature measurement device significantly can reduce the deviation to the reference sensor compared with a single Pt-100 sensor. Relative reductions in the deviation to the reference of 20-85 % were possible to achieve. This opens for the possibility of increasing the energy efficiency in power plants as aimed for in the ENG-06 project.
Accurate temperature measurements in flow lines are critical for many industrial processes. It is normally more a rule than an exception in such applications to obtain water flows with inhomogeneous temperature distributions. In this paper, a number of comparisons were performed between different 100 ohm platinum resistance thermometer (Pt-100) configurations and a new speed-of-sound-based temperature sensor used to measure the average temperature of water flows with inhomogeneous temperature distributions. The aim was to achieve measurement deviations lower than 1 K for the temperature measurement of water flows with inhomogeneous temperature distributions. By using a custom-built flow injector, a water flow with a hot-water layer on top of a cold-water layer was created. The temperature difference between the two layers was up to 32 K. This study shows that the deviations to the temperature reference for the average temperature of four Pt-100s, the multisensor consisting of nine Pt-100s, and the new speed-of-sound sensors are remarkably lower than the deviation for a single Pt-100 under the same conditions. The aim of reaching a deviation lower than 1 K was achieved with the speed-of-sound sensors, the configuration with four Pt-100s, and the multisensor. The promising results from the speed-of sound temperature sensors open the possibility for an integrated flow and temperature sensor. In addition, the immersion depth of a single Pt-100 was also investigated at three different water temperatures.
The feasibility of using laser photodetachment as a means for isobar suppression in accelerator mass spectrometry has been investigated for the special case of HfF5-/WF5-. A method for absolute photodetachment cross section measurements was applied and the cross sections of tungsten pentafluoride and hafnium pentafluoride negative ions were measured. The measurements indicate that the photodetachment cross section for WF5- is at least 100 times larger than for HfF5- at the wavelength of the fourth harmonic of the Nd:YAG laser at 266 nm. The absolute cross section for WF5- at this photon energy was found to be (2.8 ± 0.3) × 10-18 cm2, while an upper limit of 2 × 10-20 cm2 was obtained for the HfF5- cross section. The measured cross sections indicate that an optical filtering scheme for isobar suppression in accelerator mass spectrometry for the case of Hf182 should be feasible.
A Liquefied Natural Gas (LNG) flowmeter research and calibration facility is being built in Rotterdam by the Dutch metrology institute VSL. This cryogenic test loop will also be used to test and develop LNG analysers, new technologies and devices for measurement of LNG physical properties. The facility will consist of a Primary Standard Loop (PSL) that can measure the mass of LNG flows traceable to the International Kilogram standard in Paris. The primary standard is capable of flow measurements up to 25 m3/hr. A second Midscale Standard Loop (MSL) will measure volumetric flow rate of up to 200 m3/h, expandable to at least 400 m3/h in the future. The Midscale standard is traceable to the PSL and scales the flowrate up using bootstrapping techniques. This paper describes the combined PSL and MSL facility, its objectives, and accomplishments to date.
Climate change and its consequences require immediate actions in order to safeguard the environment and economy in Europe and in the rest of world. Aiming to enhance data reliability and reduce uncertainties in climate observations, a joint research project called MeteoMet-Metrology for Meteorology started in October 2011 coordinated by the Italian Istituto Nazionale di Ricerca Metrologica (INRiM). The project is focused on the traceability of measurements involved in climate change: surface and upper air measurements of temperature, pressure, humidity, wind speed and direction, solar irradiance and reciprocal influences between measurands. This project will provide the first definition at the European level of validated climate parameters with associated uncertainty budgets and novel criteria for interpretation of historical data series. The big challenge is the propagation of a metrological measurement perspective to meteorological observations. When such an approach will be adopted the requirement of reliable data and robust datasets over wide scales and long terms could be better met.
The study describes significant outcomes of the ‘Metrology for Meteorology’ project, MeteoMet, which is an attempt to bridge the meteorological and metrological communities. The concept of traceability, an idea used in both fields but with a subtle difference in meaning, is at the heart of the project. For meteorology, a traceable measurement is the one that can be traced back to a particular instrument, time and location. From a metrological perspective, traceability further implies that the measurement can be traced back to a primary realization of the quantity being measured in terms of the base units of the International System of Units, the SI. These two perspectives reflect long-standing differences in culture and practice and this project – and this study – represents only the first step towards better communication between the two communities. The 3 year MeteoMet project was funded by the European Metrology Research Program (EMRP) and involved 18 European National Metrological Institutes, 3 universities and 35 collaborating stakeholders including national meteorology organizations, research institutes, universities, associations and instrument companies. The project brought a metrological perspective to several long-standing measurement problems in meteorology and climatology, varying from conventional ground-based measurements to those made in the upper atmosphere. It included development and testing of novel instrumentation as well as improved calibration procedures and facilities, instrument intercomparison under realistic conditions and best practice dissemination. Additionally, the validation of historical temperature data series with respect to measurement uncertainties and a methodology for recalculation of the values were included.