Design suggestions on modified self-sustainable space toilet

Shreyash A Sakhare,Eva Gupta,Gyanendra Kumar Singh,Girish C Verma,Nand Jee Kanu,Sourabh M Pendkar,Umesh Kumar Vates

doi:10.1007/s42452-021-04878-w

Abstract

The present research investigates the design of compact and lightweight waste collection system (WCS) for interplanetary missions such as Mars, and the Moon as well as the space with the required features of NASA’s lunar loo challenge (released date: 25th June, 2020). Existing space toilets’ WCS store waste in small plastic bags and these bags are thrown in the space which increases the space junk. If these WCS are used on planets, they could pollute the planets. The newly designed—unisex and self-sustainable space toilet meets its objective of intimacy and warmth for the astronauts as it is equipped with all essential features such as (a) the basin for vomit collection, (b) the rotating waste storage based on the mechanism of artificial gravity, and (c) the noiseless bellow pump for air flow flushing system (AFFS). The WCS is designed for the storage of urine, faeces, vomit, diarrhoea, and menses. In the first half of the research article, the focus is kept on improving self-sustainability of the present WCS. In the second half of the present investigation analyses are done for multiphase flows of the CFD analysis in ANSYS fluent to simulate the flow of air through the nozzle provided with (a) the seat, (b) the urine funnel, and (c) the basin for air flow flushing system (AFFS). The design of the present self-sustainable space toilet proposed herewith is justified suitable for different gravitational conditions such as (a) Mars (3.721 m/s2), (b) the Moon (1.62 m/s2), and (c) the zero—or microgravity i.e., the space gravity. The proposed solar-operated WCS could be integrated to function with (a) water recovery and management (WRM) system, (b) the inbuilt composting unit, and (c) the bioregenerative life support system (BLSS). Furthermore, the assessment of the required electrical energy derived from the solar energy (harnessed using efficient solar photovoltaic (PV) modules) is conceptualized for the effective functioning of the present self-sustainable WCS.Article highlightsThe present investigation explores into the design of lightweight and compact WCS for interplanetary missions such as Mars and the Moon, as well as space missions with the functionality listed by NASA's lunar toilet competition (released date: 25th June, 2020).The actual space toilets, which are used on the International Space Station (ISS), are not designed to withstand varying gravity circumstances.The new advanced—unisex and self-sustaining space toilet achieves its goal of intimacy and warmth for astronauts by including all necessary features such as (a) a vomit collection basin, (b) rotating waste storage based on artificial gravity mechanism, and (c) a noiseless bellow pump for air flow flushing system (AFFS).

Highlights

Human space exploration is increasing year after year
The increasing space exploration demands self-sustainable technology which is fictional for all its requirements [1,2,3]
The analyses are done in multiphase flows of the Computational fluid dynamics (CFD) analysis in ANSYS fluent

Summary

Introduction

Human space exploration is increasing year after year. The planet should be habitable to every resource needed for living. One of those essential needs is a waste collection system (WCS) that can work in any gravitational and microgravity conditions. The increasing space exploration demands self-sustainable technology which is fictional for all its requirements [1,2,3]. The space and planets may lack some essential resources for habitation and interplanetary exploration. Every technology in the space must use minimum resources to function properly. One of those technologies is a WCS as a universal waste management system (UWMS) [4,5,6]

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Discussion

Conclusion