Embedded optical fiber sensors (OFS) are an emerging technology that can address real-time monitoring of wellbore integrity for carbon storage, oil/gas, and geothermal systems. Optical fiber sensors are capable of physical and chemical monitoring to observe the structural health of wellbores during operations. While embedded sensors add real-time monitoring capabilities, it is vital to understand how they interact with cement to impact the physical, mechanical, and flow properties of the cement in a well. Previous results showed that embedded OFS prototypes improved cement mechanical strengths and increased the axial permeability when OFS ran through the full length of the cement core. To simulate the most susceptible part of a cemented well, OFS prototypes were embedded within cement with a cement end cap at one end. The samples were then CT scanned for sample visualization and to determine the end cap thickness. Physical and mechanical properties (porosity, permeability, Young’s modulus, etc.) were measured on the sensor embedded cement samples. The cement cap demonstrated promising results in mitigating the undesired permeability increase for the OFS prototypes, while largely maintaining the mechanical enhancement.
There is a need for embedded sensor technologies to monitor wellbore integrity in real-time for carbon storage and geothermal applications. Emerging sensing technologies such as optical fiber sensors and wireless sensors have been studied for physical parameter monitoring (e.g. temperature, vibration, and strain) and chemical parameter monitoring (e.g. pH, CO2, corrosion) to monitor structural health of the wellbore. The desirable sensors need to be able to withstand the harsh environments relevant for carbon storage and geothermal wellbores, and they must not inadvertently cause potential sources of wellbore failures. Therefore, we investigated the cement properties with embedded sensors to compare with baseline cement properties, including porosity, permeability, mechanical properties (e.g. Young’s modulus, Poisson’s Ratio, etc), and 3D computed tomography (CT) scans. The sensor devices (optical fiber sensors [OFS] and wireless chip sensors) were embedded in cement cores under wellbore relevant conditions. Then, the cement samples were examined using AutoLab 1500, nitrogen permeability testing, helium porosity testing, and 3D CT scanners. Results show that the cement samples with embedded sensor devices had a slight increase in porosity of 1.5% to 3.6% compared to the blank cement samples. Permeability slightly increased by 0.001 mD with embedded chip sensors. The embedded chip sensors did not significantly change the cement mechanical properties; whereas, the embedded OFS prototypes improved the cement mechanical strengths, e.g. increasing the Young’s modulus by as much as 10% and the bulk modulus by up to 25.5%. CT scans confirmed the proper embedding and good bonding between sensor devices and cement.
Current methods for guiding cancer biopsies rely almost exclusively on images derived from X-ray, ultrasound, or magnetic resonance, which essentially characterize suspected lesions based only on tissue density. This paper presents a sensor integrated biopsy device for in situ tissue analysis that will enable biopsy teams to measure local tissue chemistry in real time during biopsy procedures, adding a valuable new set of parameters to augment and extend conventional image guidance. A first demonstrator integrating three chemical and biochemical sensors was tested in a mice strain that is a spontaneous breast cancer model. In all cases, the multisensory probe was able to discriminate between healthy tissue, the edge of the tumor, and total insertion inside the cancer tissue, recording real-time information about tissue metabolism.