Modelling of load effect on macro-bend losses for a singlemode-multimode-singlemode (SMS) fiber structure with small bend radius is presented. Load effect on macro-bend losses for the SMS fiber structure placed between two high-density polyethylene (HDPE) boards are investigated theoretically and experimentally. A model on macro-bend losses for SMS fiber structure is constructed by using the light transmission formula in a straight SMS fiber structure and taking into account the effective number of guided modes due to the macrobending. In the experimental, a mandrel with a diameter of 0.8 mm is used to induce the bend. When the loads are applied on the system, the mandrel will affect the bend losses for the SMS fiber structure. It is shown numerically and experimentally that the bend-loss of SMS fiber structure strongly depends on the applied loads and the multimode fiber (MMF) lengths.
Crude oil is a products of oil and gas industries. One of the parameters which has in crude oil is specific gravity. In the oil and gas industries, specific gravity is used to classify crude oil which to be produced. specific gravity can be measured using ASTM D-1298 method. Disadvantage of this method is there are need of special environments and still using manual transcription. This research has been conducted a crude oil specific gravity sensor design by implementing structural imperfect to improve the performance of specific gravity sensors. In this research, polymer optical fiber is used as a sensor to measure specific gravity of crude oil. There are three variation of the amount of defect that were used in this research. Sample which used in this research has span of specific gravity value from 0,842218 to 0,9097. Based on the result, sensor with 3 imperfect structure have the best performance with linearity coefficient value 0,9438 and the span of measurement is 1,75792 dBm.
Alcohol sensor based on Single-mode -Multimode-Single-mode (SMS) fiber structure is being proposed to sense alcohol concentration in alcohol-water mixtures. This proposed sensor uses refractive index sensing as its sensing principle. Fabricated SMS fiber structure had 40 m of multimode length. With power input -6 dBm and wavelength 1550 nm, the proposed sensor showed good response with sensitivity 1,983 dB per % v/v with measurement range 05 % v/v and measurement span 0,5% v/v.
Alcohol is volatile and flammable liquid which is soluble substances both on polar and non polar substances that has been used in some industrial sectors. Alcohol detection method now widely used one of them is the optical fiber sensor. In this paper used fiber optic sensor based on Multimode-Single-mode-Multimode (MSM) to detect alcohol solution at a concentration range of 0-3%. The working principle of sensor utilizes the modal interference between the core modes and the cladding modes, thus make the sensor sensitive to environmental changes. The result showed that characteristic of the sensor not affect the length of the single-mode fiber (SMF). We obtain that the sensor with a length of 5 mm of single-mode can sensing the alcohol with a sensitivity of 0.107 dB/v%.
A sensor based on a fiber optic hetero-structure to determine the concentration of alcohol has been proposed. The structure of the sensing probe in this research is a singlemode-multimode-singlemode (SMS) which bent into Ushaped and soon called as SMS u-bent. The SMS structure was chosen to get a higher sensitivity. This research utilizes the principle of multimode interference and evanescent field by modifying the cladding with various alcohol concentration. Testing of the sensor’s performance has been done by measuring the sensor’s power output response to the length of the SMS fiber optic, bending diameter, and alcohol concentration. Based on the experiment result, the ubent SMS fiber optic with 50 mm bending diameter and 63 mm MMF lenght has the highest sensitivity, 3.87 dB/% and the minimum resolution, 0.26 x 10<sup>-3</sup> %.
In this paper, a load effect on a singlemode-multimode-singlemode (SMS) fiber structure embedded in a high-density
polyethylene (HDPE) was investigated numerically and experimentally. It was modelled that the applied load induces a
longitudinal strain on the HDPE and accordingly affects the SMS fiber structure’s parameters. It was calculated the
output power of the SMS fiber structure using a graded index multimode fiber (MMF) due to the applied strain from 0 to
4000 N. The experimental result shows that for the MMF length of 105 mm, the output power has monotonically
increasing for an applied load range from 1700 to 4000 N with a sensitivity of 1.18 x 10<sup>-3</sup> dBm/N. This configuration of
SMS fiber structure embedded in the HDPE is potential for a load sensor.
Temperature sensing based on a singlemode-multimode-singlemode (SMS) fiber structure with a graded index
multimode fiber (GI-MMF) type using an intensity-based interrogation has been investigated numerically and
experimentally. The effect of temperature on the SMS fiber structure with the MMF-GI type was modeled using a modal
propagation analysis (MPA). The SMS fiber structures for temperature sensor was fabricated and tested with the MMF
length of 57 mm. It is demonstrated experimentally, and supported with numerical results, that the sensor showed a
sensitivity of 0.063 dB/°C with a temperature measurement range of 175-325°C. This sensor offers simple configuration
and low cost of fabrication for the temperature measurement applications.