Non-dispersive infrared (NDIR) gas sensors applied in an environmental field are considered. Disadvantages of the non-dispersive infrared (NDIR) gas sensors include spectral interference and high detection limit. Efforts to improve these disadvantages are reviewed in this paper. Interference caused by water vapor and gas matrix has been partially solved using optical filters and interference correction factors. Limitations such as accuracy and sensitivity of the sensor were overcome by the improvements of inlet gas concentrations, infrared sources, optical designs (including optical filter and gas chamber) and detectors. These improvements are limited to a few gases, in particular, carbon dioxide. Drawbacks related to water vapor still remain and need to be addressed.

A review on non-dispersive infrared gas sensors: Improvement of sensor detection limit and interference correction

Waste heat recovery from diesel engines based on Organic Rankine Cycle

Power production from low grade heat and waste heat does not only mitigate environmental impact but also improve energy efficiency and reduce energy cost. The type and design of expander for a low grade heat engine are critical and affect the performance, efficiency and cost of low grade heat and waste heat recovery system. The choice of expansion machine is strongly correlated with operating conditions, working fluid and size of the system. Low grade heat and waste heat recovery systems for electricity production are usually smaller in size. Turbines cannot be used due to their high rotational speed and high cost for waste heat and low grade heat recovery systems less than 50 kWe. Therefore, volumetric expanders are more suitable in low grade heat and waste heat engines for a smaller size. The current paper provides a comprehensive review of volumetric expanders including vane expander, screw expander, scroll expander, and piston expander applications for low grade heat and waste heat recovery using organic Rankine cycle. The operational performance, design optimizations, leakage and frictional losses, modeling techniques for each type of expander has been investigated in detail. Technical constraints and operational performance of expanders have been analyzed followed by the comparative assessment based on their performance, current market status, and economics. The comparative assessment shows that screw expander and scroll expander are most suitable having a relative score of 73.6 and 70.4 respectively on a scale of 100. The vane expanders have the lowest score of 47.2 due to low power range, leakage and frictional losses, and technical complexities.

Volumetric expanders for low grade heat and waste heat recovery applications

Review of Organic Rankine Cycle experimental data trends

Design and experimental investigation of a 1 kW organic Rankine cycle system using R245fa as working fluid for low-grade waste heat recovery from steam

The Application of Rotary Vane Expanders in Organic Rankine Cycle Systems—Thermodynamic Description and Experimental Results

Modelling and experimental analyzes on air-fluidised silica gel-water adsorption and desorption

A numerical study of a looped-tube thermoacoustic engine with a single-stage for utilization of low-grade heat

Pyroelectric and dielectric energy conversion – A new view of the old problem

The thermal radiation of a black body is investigated using a pyroelectric infrared radiation detector. This paper presents the construction and operation principles of a simple set-up used for investigation of black body radiation in a student laboratory, and the laws of black body radiation are briefly described. Using the measuring system presented in this paper, it is possible to show the relationship between energy emitted by a black body model and its temperature, as well as verifying the Stefan–Boltzmann law. Knowledge of black body radiation laws and the operation principles of pyroelectric detectors for infrared radiation is essential to understand many processes in nature, the operation principles of different devices including certain systems used in renewable energy sources, alarm systems and methods of measurement used in science and technology.

https://iopscience.iop.org/article/10.1088/0143-0807/36/6/065025/pdf

Zbigniew Gnutek

Papers

The Application of Rotary Vane Expanders in Organic Rankine Cycle Systems—Thermodynamic Description and Experimental Results

Modelling and experimental analyzes on air-fluidised silica gel-water adsorption and desorption

A numerical study of a looped-tube thermoacoustic engine with a single-stage for utilization of low-grade heat

Pyroelectric and dielectric energy conversion – A new view of the old problem

Investigation of black body radiation with the aid of a self-made pyroelectric infrared detector