Flow through various porosity of circle grid perforated plate with orifice plate flowmeter

Most of the plant industry is required to measure the flow rate more accurately to meet plant operation and cost accounting objectives. The opposing concern of improving flow meter accuracy is resolved by using flow conditioners. The distance of implementation of flow conditioner upstream of the orifice plate flowmeter also needs to be addressed. The purpose of this study is to analysis the porosity of the circle grid perforated flow conditioner towards orifice plate flowmeter’s accuracy and to determine the ideal distance of flow conditioner upstream of the orifice plate flowmeter. In this investigation, a variety of designs of the flow conditioners based on a porosity were installed with different distance upstream of the orifice plate in conjunction with the different disturbances to assess the effects of these devices on the measurement of the mass flow rate. Experimental investigation depends on three patterns of the perforated plate in a variety of diameter ratio or porosity which is β equals to 0.38 for the first plate, 0.5 for the second plate and 0.7 for the final plate. These fractal patterns will then react to five openings of speed controller of the centrifugal inline fan. Data gains for all three plates showed that there is an increment of pressure drop and change in discharge coefficient of the orifice with lower β value of fractal flow conditioner. This investigation also compares the various distance of flow conditioner upstream of the orifice plate flowmeter, thus proved that shorter pipe length produced higher pressure drop

Capacitive coupling of discrete micro-sized gaps for RF applications

This paper investigates the performance of a passive thin metallic object containing micro-sized gaps exposed to a plane wave excitation. This work has potential applications for emerging antenna fabrication techniques where the conducting sections are made from discrete metallic sections. This includes antennas composed from nanomaterials and conventional inkjet printed antennas. Electromagnetic simulations showed metallic sections separated by a micro-sized gap were found to capacitively couple. The coupling can be enhanced by reducing the size of the gap, increasing the width of the metallic object or by filling the gap with a permittivity greater than unity. It should be noted that the DC value of parallel plate capacitor is not strictly valid at radiofrequencies – however, this paper shows that the DC value of capacitance is a reasonable approximation and is useful to understand the behavior

Resistivity Characterization For Carbon Based Conductive Nanocomposite On Polyethylene Terephthalate And Thermoplastic Polyurethane Substrates

Nanotechnology has gained a lot of focus in recent years due to its application in multidisciplinary fields such as chemistry, electronics energy, and biology. Wearable electronic consists of nanocomposites liquid-solid conductive ink and flexible substrate. This study characterizes the electrical characteristic of the conductive ink with unloaded condition. The conductive ink was printed with four patterns; straight, curve, square and zig-zag patterns. Sheet and bulk resistivity results indicated the decrement of resistivity of all four patterns with the increase of the conductive ink width. From the result, it showed that the resistivity inside the conductive ink increased such as constriction resistance, tunnelling resistance and the number of squares of the meandering trace as compared to similar lengths of a straight-line trace. Size of the particle also affected the contact area and electrical flow between the conductive ink particles. Meanwhile, individual results for each pattern had its own function inside the circuit trac

Impedance and resistance of carbon ink during cure

The resistivity of cured conductive ink films are dependent on a wide range of process parameters. An early indication of the resistivity that is likely to result following curing can enable these parameters to be optimised and, therefore, improve product quality. This paper aims to report on the use of alternating current (AC) impedance measurement techniques on curing printed ink films as a means of assessing the resistivity likely to be attained following the curing process. Design/methodology/approach - Impedance measurements (100 Hz-10 MHz) were performed on curing conductive carbon ink films printed on polyethylene terephthalate substrates during convective heat curing. A jig was designed to incorporate the test structure in an convection oven such that the effect of cure on the structure impedance could be investigated. Findings - The initial impedance was found to decrease with an increase in the measurement frequency. As the ink films were cured, the impedance magnitude across the 100 Hz-10 MHz range converged with the direct current (DC) resistance value. For a given ink, the ratio of initial AC impedance at 10 MHz to final cured resistance was found to be consistent, thus giving a method where final conductivity can be estimated before cure. Originality/value - Data from printed ink resistance measurements are required to ensure the optimal conductivity of printed devices. However, after the printed structures are fabricated and cured, it is too late to optimise process parameters, leading to significant wastage. AC impedance measurement can give an indication of the final cured resistivity whilst the structure is freshly printed and still in its curing phase, enabling the printing process parameters to be adjusted to improve the resistivity of subsequently printed devices. Measuring AC impedance of printed ink structures in a production environment can, therefore, improve output

Optimization of fabrication parameters for inkjet printed RFID tags on paper-based substrates

Inkjet printing is a non-contacting additive depositing method for fabricating electric devices on versatile substrates, which provides a great potential for different Internet of Things (IOT) applications. It enables fast, cost-effective, and environmentally friendly production. Paper-based substrates, like coated paper, uncoated paper, and cardboardare used for printed patterns, and silver nanoparticle ink is applied in this study. Printed layers need to be sintered to form conductive traces, and in this experiment, thermal sintering is selected, since it is easy to operate and has stable performance. The aim of this thesis is to study the possibility of inkjet printing on paper-based substrates using silver nanoparticle ink and to optimize the printing parameters for fabricating passive ultra-high frequency (UHF) radio frequency identification (RFID) tags on these substrates. A simple line pattern with dimension of 5mm × 30 mm was first printed on these substrates to evaluate the conductivity, and surface magnified images from the optical microscope were taken to analyze the performance. The silver nanoparticle ink was successfully sintered with thermal sintering on three paper substrates and four cardboards. For every substrate, specific printing parameters and layers are needed to achieve best conductivity performance. Then, inkjet-printed UHF RFID tags were fabricated on these substrates. According to our measurements, the tags on paper substrates showed peak read ranges of 4 – 6.5 m, and the tags on cardboard substrates exhibited peak read ranges of 1 – 6 m. Based on these results, the performance of these inkjet-printed UHF RFID tags is sufficient for many IOT devices and potential applications

Novel Manufacturing Methods and Materials for UHF RFID Tags in Identification and Sensing Applications

The continuously increasing amount of radio frequency identification tags needed in our daily lives, not forgetting the broadly widening concept of the Internet of Things, sets high demands on the tag materials selection and manufacturing processes. The huge amount of needed tags requires environmentally sustainable material selection together with the requirement of very low cost. In addition, the manufacturing capacity needs to be very high, hence high-volume capable production methods are needed. In addition to identification applications, also sensing applications established with radio frequency identification tags are of great interest in many application fields.This thesis reports the possibilities of radio frequency identification tags manufactured on eco-friendly substrate materials using conductive inks and photonic sintering. The used manufacturing methods use raw materials efficiently. Especially brush-painting together with photonic sintering is capable for low-cost high-volume manufacturing. In addition, the possibilities of radio frequency identification tags for humidity sensing applications are studied.The results of this thesis confirmed that the materials and processes studied in this thesis are suitable for environmentally friendly low-cost radio frequency identification tag manufacturing. Especially brush-painting of regular screen printing conductive inks, both silver and copper oxide ink, on wood and cardboard substrates combined with photonic sintering confirmed to be a very good choice for the application area focused in this thesis. Furthermore, especially the use of screen printable copper oxide ink for identification applications is a very low-cost possibility. The results showed that humidity sensing with passive ultra-high frequency radio frequency identification tags, which were manufactured with regular screen printing silver ink on wood substrate without any coating on the tag, is a very promising approach

Analysis of Current State of The Art of RFID IC Chips

Radio Frequency Identification (RFID) is a constantly developing technology particularly in the ultra-high-frequency (UHF) band for its long operating range, power efficiency, and maintenance-free characteristics. It has been successfully developed for many applications already, that includes identification, sensing, tracking, monitoring, etc. In terms of tag, the integrated circuit (IC) or chip play an essential part in the functionality of the tag, where logical information is programmed into. Nowadays, the chips come in a variety of memory options, sensitivity, supported protocols, with an optional battery-assisted mode, additional commands, and features. There are various methods that are followed to fabricate RFID tags, i.e. inkjet-printing, painting, 3D printing, etching, etc. On the way of completion of these procedures, some of the methods involve the use of chemicals, producing waste, which is unfavorable in respect of the cost, and as well as the environment. In addition, the substrate impacts tag’s performance. If the tag is going to be attached for instance, on a metal surface the radiation properties of the tag antenna would experience changes, as the electromagnetic waves will reflect on the metal surface, which will basically degrade tag’s performance. Maintaining multiple applications on a single chip has become common to a certain extent. It requires additional power than usual, which is an issue for passive tags. In order to overcome this hurdle, energy harvesting system is required, which is going to suffice the need for a power source. In this paper, the functionalities and applications of the RFID chips have been reviewed and some suggestions have been proposed on how RFID can be commercially manufactured, in terms of fabrication methods, supplying enough power for applications, and ensuring security of the tagged object

Carbon Nanotube Loaded Passive UHF RFID Sensor Tag with Built-in Reference for Wireless Gas Sensing

Radio Frequency IDentification (RFID) technology, which uses communication by means of reflected power, is used for the wireless identification of objects. Individual objects are identified by the RFID tag placed on them. An RFID tag consists of a microchip and an antenna. An RFID reader transmits radio frequency (RF) waves to identify the tagged objects. It transmits identification information, which is stored in its memory, through back scattered radio waves to the RFID reader. Passive RFID tags harvests RF energy from the reader device to power its microchip, enabling battery free operation. Passive wireless sensors based on UHF RFID technology are a promising prospect in the realm of ubiquitous sensing and Internet of Things (IoT). The sensing principles and methods used depend on the variation of the tag antenna gain, the impedance match between the tag antenna and the RFID chip, or both, with respect to the sensed parameter. The RFID reader uses back scattered RF signal properties to perform sensing. Usually, threshold power, the power at which an RFID tag harvests enough power to turn itself ON, or back scattered signal power, is used for sensing measurements. These measurements depend heavily on the environment, where the tag is placed, and the distance at which it is measured by a reader. This poses severe restrictions in sensing measurements. To maintain sensor accuracy, precise calibration of the measurement setup is required. Any disturbance in the measurement setup or the RF propagation environment affect the sensor measurement. This thesis presents a novel architecture of inkjet-printed passive UHF RFID based sensor tag that allows a reference measurement and sensing measurement for wireless gas sensing. In this work, an RFID tag is made with Silver (Ag) ink, and is loaded with carbon nanotube (CNT) ink for sensing purpose. Carbon nanotubes (CNT) have a property that it modifies its conductivity in the presence of certain gases. This property is exploited for sensing (CO2) gas. A switch, used in the sensor tag’s structure, provides two modes of operation. They are, sensor on (SON) or sensing mode operation, and sensor off (SOFF) or reference mode operation. In SON mode, the sensor tag modifies its backscatter properties in the presence of gas. In SOFF mode, the realized gain of the sensor tag remains constant in the presence of gas, which provides a reference measurement. The difference in threshold power, between SON mode and SOFF mode is used as the sensing parameter. This sensing paradigm allows sensor measurements that do not depend on the RF propagation conditions, or the distance of the reader. The fabricated sensor tags, when exposed to CO2, show a threshold power variation of up to 2dB, with a read range of about 4m at 915MHz. This means, threshold power difference between SON and SOFF mode provides unambiguous detection of CO2 at all measurement conditions. Study and measurements done in this work prove the feasibility of gas detection by placing CNT very close to the tag, instead of, on the tag. More importantly, the concept of using a switch in the sensor tag to provide reference measurement is proven. Several possibilities exist in the realization of the switch including, but not limited to, incorporating the switch within the RFID chip. These ideas will be explored in future work