Saurabh Tiwari

TL;DR: In this article, the authors studied the synthesis of MWCNTs using polypropylene waste as a precursor and Ni/Mo/MgO as a catalyst by the combustion technique.

TL;DR: In this paper, Taguchi method coupled with grey relational analysis was used to optimize the design parameters of a metal hydride-based thermal energy storage system, including diameter of helical tube (dh), major diameter (DM), number of turns, and velocity of heat transfer fluid (Vf).

TL;DR: This paper proposes a deep-learning based approach to road surface quality monitoring, using accelerometer and GPS sensor readings, which enables several useful smart-city applications such as spatio-temporal monitoring of the city's roads, early warning of bad road conditions, as well as choosing the "smoothest" road route to a destination.

Abstract: In solar water heating systems, geometrical configurations of thermal energy storage (TES) play a crucial role in the enhancement of system performances. Upon conducting a thorough study on the influence of different shapes and aspect ratios of TES tanks, the present study focuses on the choice of suitable TES tank geometry based on the key performance parameters, viz. Richardson number, stratification number, storage efficiency and the initial thermocline thickness. Thermal stratification characteristics are investigated and analyzed in detail for three chosen shapes of TES, namely truncated-cone, paraboloid, and cylinder, using a two-dimensional unsteady numerical model. Results of the numerical model on cylindrical TES is found to have good agreement with the findings of the in-house experiments. With increasing aspect ratio (AR) of the paraboloid and truncated cone TES tanks, initial thermocline thickness and the energy losses increase, whereas, Richardson number and average stratification number decrease, indicating better stratification performance in storage tanks with lower AR. However, there is a limit on reducing the AR. At every AR investigated for the two shapes of TES, Richardson number for the paraboloid TES is greater than that of the truncated-cone TES, qualitatively suggesting a better temperature stratification in the paraboloid TES. The effect of flow rate on the thermal stratification characteristics is also studied, which suggests that increasing the flow rate enhances mixing and deteriorates stratification. The findings can be used as guidelines for designing TES with improved thermal performance.

TL;DR: In this paper, Taguchi method coupled with grey relational analysis was used to optimize the design parameters of the helical tube heat exchanger embedded inside metal hydride bed to achieve minimum desorption time (TD) for 80% desorptions and minimum outlet temperature (T0) of heat transfer fluid (HTF).